Schlüsselwort: dairy cows

Untersuchungen zum Transitkuhmanagement in ostdeutschen Milchviehbetrieben sowie zum Einfluss der Vorbereitungsdauer unter Einsatz saurer Salze auf die Gesundheit und Leistung von Milchkühen in der Frühlaktation

Untersuchungen zum Transitkuhmanagement in ostdeutschen Milchviehbetrieben sowie zum Einfluss der Vorbereitungsdauer unter Einsatz saurer Salze auf die Gesundheit und Leistung von Milchkühen in der Frühlaktation von Neuhaus, Lisa-Katharina
"Evaluation of transition cow management in East German dairy farms and the association between exposure length to a prepartum negative DCAD diet and health and performance in the subsequent lactation of Holstein dairy cows" The objective of the first part of this study was to evaluate the housing and management practices in the transition period on East German dairy farms with particular focus on farms feeding a negative DCAD in the prepartum diet. Therefore, 18 farms were visited twice 2 weeks apart. We assessed (1) facility design, (2) housing system, (3) feeding management, and (4) animal health of dry cows, high pregnant heifers and fresh cows. Due to that, the stocking density were assessed in the transition groups on the 18 farms. In a subsample of cows (≥ 12) from each farm we evaluated urinary pH, net acid excretion, urinary calcium and blood NEFA, calcium and BHB. For monitoring the feeding management we analyzed the TMR regarding the ingredients, the consistency and mix quality, the sorting of TMR by dairy cows as well as the dry matter intake in the transition groups. Furthermore, a time lapse camera was installed for one week in the close-up pen and the fresh pen to evaluate the feed bunk management. The present study revealed that transition cow management might be improved on the 18 farms enrolled. Particular, monitoring of urinary pH on a weekly basis to control acidification in prepartum cows was adopted only on 2 of 18 dairy farms. The lack of regular monitoring of urinary pH led to a strong variation in urinary pH, net acid excretion and calcium levels. In only 6 of 18 herds, the average urinary pH was within the target range of 5.8 to 7.0 at both sampling times. Urinary pH was varying within the 12 cows sampled at one day, but also across the two farm visits. In addition, more than 50% of the investigated close-up groups were overcrowded, which meant that the animals did not have an adequate supply of feeding space, water locations and resting space. The evaluations of the time lapse cameras showed that the animals in the transition groups did not have permanent access to feed and that the duration of feed deprivation was quite long. Only in few close-up and fresh groups could (1/18 and 2/13) ensure that the cows did have permanent access to feed. Moreover, the supply with water troughs was insufficient in 75 % of the transition groups (43/57). The resulting competition for feed, water, and resting space may lead to increased stress levels and have negative effects especially for submissive, smaller and younger heifers and cows on their health and performance. In 16 farms, the calving pens represented groups of 2 to 15 cows. In addition, in 6 farms, apart from the move to the calving pen, regroupings during the close-up period (≈1 to 10 days a.p.) was firmly established in the transition cow management. These can result in reduced dry matter intake, lying time, as well as milk production due to the associated stress. The prevalence of hypocalcemia (< 2.0 mmol/L) and subclinical ketosis (BHB > 1.2 mmol/L) was 32.8 % (63/192) and 38.4% (89/232) in 18 dairy herds. In 4 of 18 herds, the prevalence of hypocalcemic cows was classified as problematic (> 41.7 %). The increased prevalence of subclinical ketosis in the studied herds (38.4 %) is higher than reported in the international literature. These results show that feeding of anionic diets in the close-up group in order to improve peripartum calcium homeostasis requires appropriate management, especially in the context of facility design and feeding management. Feeding of a negative DCAD diet can be conducted successfully, if urinary pH is assessed routinely, based on a weekly subsample of cows. Herd management is also considered to be of great importance in order to decrease susceptibility to ketosis (e.g., permanent access to feed; minimizing the social and environmental stress). Moreover, dry matter intake must be evaluated regularly to control for sufficient energy intake. The present study shows that there is a need for optimization regarding of transition cow management in Eastern German dairy farms feeding a negative DCAD diet in the close-up group. The objective of the second part of this study was to evaluate the association between the exposure length to a prepartum negative DCAD diet and milk yield, milk components, reproductive performance and culling risk in the subsequent lactation. During the observation period 20,373 cows were calving on the participating 18 farms. A total of 13,314 animals (3,871 heifers and 9,443 cows) were included in the final statistical analysis. We observed considerable variation of exposure length to negative DCAD diet among farms. For primiparous cows, there was a linear association between days in the close-up group (DINCU) and milk yield at first test day (P < 0.001). An exposure length of 35 to 36 days to a negative DCAD diet was associated with the highest milk yield at first test day (35.45 kg/day; 35.43 kg/day). Primiparous cows with 35 DINCU had 3,47 kg higher milk yield at first test day than primiparous cows with 7 DINCU. Multiparous cows with 26 DINCU had the highest milk yield at firs test day (41.64 kg ± 0.33 SEM). Multiparous cows with 26 DINCU had 2,9 kg higher milk yield at first test day than multiparous cows with 7 DINCU. A plateau in milk yield was observed between 22 and 29 DINCU. Beyond 29 DINCU, however, was associated with a mild decrease in milk yield at first test day of multiparous cows. In the present study a linear association (P < 0.001) between DINCU and the ratio of fat and protein at first test day in multiparous cows was observed. The ratio of fat and protein increased slightly with extended DINCU. In 3 previous studies, did not detect a significant effect of DINCU on fat and protein content in milk (Weich et al., 2013, Wu et al., 2014, Lopera et al., 2018). There was a significant association between DINCU and somatic cell count at first test day in primiparous (P = 0.005) and multiparous cows (P = 0.011). The longer cows stayed in the close-up group, the higher was the linear score at first test. In the present study, there was no significant association between DINCU and the risk of stillbirth for either primiparous or multiparous cows. DINCU had a significant effect on culling within the first 60 days in milk for multiparous cows (P = 0.025). Multiparous cows with 1 to 6 DINCU had the greatest hazard of being culled within the first 60 days in milk. There was no significant association between DINCU and days open within the first 150 days in milk for either primiparous or multiparous cows. A short stay in the close-up group should be avoided to improve milk yield at first test day and to minimize culling risk for multiparous cows. In addition, a long exposure length to negative DCAD diet (>30 d) was associated with detrimental effects on milk production and milk components in multiparous cows and linear score of primiparous and multiparous cows. Accordingly, for multiparous cows, an exposure length of 22 to 29 days to a negative DCAD diet in the close-up group can be considered as optimal. For heifers, there is a linear association between the DINCU and milk yield in first test day. For both, cows and heifers, DINCU of < 7 days should be avoided.
Aktualisiert: 2023-02-16
Autor:
> findR *
> Buchhandlung findr > Verlag findr > Für Buchhändler

Untersuchung von Einflussfaktoren auf die postpartale Calciumkonzentration im Blutserum von Holstein-Friesian Kühen

Untersuchung von Einflussfaktoren auf die postpartale Calciumkonzentration im Blutserum von Holstein-Friesian Kühen von Crivellaro, Patricia R. H.
Die Hypocalcämie ist immer noch mit einem hohen Risikopotential für die Kühe nach der Kalbung und mit hohen Kosten durch die Behandlung und den Folgekosten verbunden. Trotz intensiver Forschungsarbeit sind immer noch nicht alle Zusammenhänge über die Entstehung von Hypocalcämien bei Milchkühen geklärt. Als eine der häufigsten Produktionskrankheiten ist es wichtig, Ansatzpunkte zu erforschen, die eine Möglichkeit bieten, der Hypocalcämie vorzubeugen. Dazu werden im Rahmen dieser Arbeit 109 pluripare Kühe der Rasse Holstein-Friesian im peripartalen Zeitraum betrachtet. Vor der Kalbung erfolgen die Untersuchungen ab 3 Wochen vor dem errechneten Kalbedatum montags und donnerstags um 6 Uhr im wöchentlichen Abstand. Direkt nach der Kalbung (Tag 0) findet eine Untersuchung statt und dann an den folgenden 3 Tagen täglich eine Untersuchung um 9 Uhr. Die Untersuchungen erfassen dabei den allgemeinen Gesundheitsstatus mittels einer Allgemeinuntersuchung und den Body Condition Score. Entsprechend dem Probenplan werden Blut- und Harnuntersuchungen sowie Rückenfettdickemessungen und Wägungen durchgeführt. Zusätzlich werden die Fütterungs-, Milchleistungs- und Krankheitsdaten erhoben. Die erfassten Daten werden unter Anwendung der Regressionsanalyse und dem Varianzmodell mit den Calciumkonzentrationen in Beziehung gesetzt. Die Calciumkonzentration im Serum nach der Kalbung wird von vielen verschiedenen Faktoren signifikant beeinflusst. Vor der Kalbung hat vor allem die Laktationszahl und die Futteraufnahme am Tag 1 a.p. eine Beziehung zu der Serumcalciumkonzentration nach der Kalbung. Mit zunehmender Laktationszahl steigt das Risiko nach der Kalbung eine Hypocalcämie zu steigen. Die Futteraufnahme um die Kalbung hat einen starken Einfluss auf die Calciumkonzentration. Je höher die Futteraufnahme in diesem Zeitraum ist, desto höher ist die Calciumkonzentration im Serum nach der Kalbung. Nach der Kalbung zeigen die Ohrtemperatur, die Pansenfüllung, die Futteraufnahme, die Calciumkonzentration, die Phosphorkonzentration und die Magnesiumkonzentration im Serum eine signifikante Korrelation mit der Calciumkonzentration im Serum p.p. Vereinzelt treten noch Zusammenhänge mit anderen Laborwerten auf. Diese sind aber nicht sehr signifikant. Wärmere Ohren und eine stärkere Pansenfüllung haben einen positiven Effekt auf eine höhere Calciumkonzentration p.p. Eine Beeinflussung durch Medikamente ist nur begrenzt möglich. Ein Zusammenhang mit der Witterung konnte nicht hergestellt werden. Durch die geringe Variabilität der DCAB konnte in dieser Arbeit kein Zusammenhang mit der Calciumkonzentration hergestellt werden, des Weiteren wird der Einfluss durch die Fütterungselemente durch die Futteraufnahme überlagert. Die Futteraufnahme zeigt ab Tag 1 a.p. einen Zusammenhang mit den Calciumkonzentrationen im Serum. Die Messwerte von Calcium, Phosphor und Magnesium im Serum beeinflussen die Calciumkonzentration im Serum p.p. entweder nur am selben Tag oder maximal ein Tag im Vorhinein. Dabei sind die Calciumkonzentrationen untereinander sowie mit den Phosphorkonzentrationen positiv miteinander korreliert. Im Gegensatz dazu zeigt sich zwischen den Magnesiumkonzentrationen mit den Calciumkonzentrationen eine negative Korrelation. Mittels der Parameter des roten Blutbildes a.p. und der Harnuntersuchung wird die Calciumkonzentration im Serum p.p. nicht stark beeinflusst.
Aktualisiert: 2021-12-23
Autor:
> findR *
> Buchhandlung findr > Verlag findr > Für Buchhändler

Tierschutzrelevante Zuchtprobleme beim Milchvieh – Interaktion zwischen dem Zuchtziel „Milchleistung“ und dem vermehrten Auftreten von Produktionskrankheiten, ein systematischer Review

Tierschutzrelevante Zuchtprobleme beim Milchvieh – Interaktion zwischen dem Zuchtziel „Milchleistung“ und dem vermehrten Auftreten von Produktionskrankheiten, ein systematischer Review von Bauer, Alina Agnes
Ziel dieses systematischen Reviews ist die Bearbeitung der im Zeitraum 1986 bis 2020 publizierten Fachliteratur zum oben genannten Thema, um einen Beitrag zur Diskussion zu leisten, den Status Quo der Fachliteratur darzustellen sowie als Grundlage für Expertengruppen zur Ausarbeitung von Handlungsempfehlungen im Bereich Milchviehzucht zu dienen. Das heutige Leistungsniveau einer durchschnittlichen Milchkuh ist hoch und zeigt seit den 1950er Jahren eine deutlich steigende Tendenz. Durchschnittliche Milchleistungen von über 9.000 kg Milch pro Kuh und 29.000 kg Milch Lebensleistungen in durchschnittlich 2-3 Laktationen verdeutlichen die Hochleistung dieser Tiere. Demgegenüber stehen die gesundheitlichen Probleme und die kurze Nutzungsdauer genau dieser Milchkühe. Die in dieser Literaturrecherche gefundenen und ausgewerteten meist genannten Abgangsgründe für das unfreiwillige Verlassen einer Kuh aus dem Betrieb sind Fruchtbarkeitsstörungen, Eutererkrankungen sowie Erkrankungen der Klauen und Gliedmaßen. Kurze Nutzungsdauern von maximal 3 Laktationen, sodass das Leistungsmaximum ab der 4. Laktation gar nicht erst erreicht wird, hohe Abgangsraten durch die unfreiwilligen Abgangsgründe und hohe Erkrankungsraten in den Milchviehherden werden in den jährlich veröffentlichten Daten des BRS sowie den Ergebnissen der aktuellen PraeRi Studie dargelegt. Die beschriebenen gesundheitlichen Probleme in der Milchviehhaltung sind abhängig von zwei Haupteinflussfaktoren, und zwar von der Genetik und der Umwelt eines Tieres. Das phänotypische Erscheinungsbild einer Milchkuh ist immer das Resultat der Mischung aus den genetischen Veranlagungen des Tieres und den äußeren Einflüssen, wie der Haltung und der Qualität des Managements. Die Ausprägung der negativen Energiebilanz (NEB) in der Frühlaktation und damit die Entstehung vieler peripartaler Erkrankungen wie Ketose, Mastitis, Metritis oder Klauenerkrankungen haben einen genetischen Hintergrund. Die Qualität des Managements und die Art der Haltung und Fütterung einer Milchviehherde ist eine Stellschraube für das Ausmaß der Erkrankungen, kann diese aber nicht verhindern. Das Grundpotential der Milchleistung, des Stoffwechsels, der NEB und damit auch der Produktionskrankheiten liegt im Genotyp des Tieres verankert. Die ausgewertete Fachliteratur sieht eine genetische Assoziation zwischen dem Auftreten verschiedener Produktionskrankheiten und der Milchleistung einer Kuh. Die Milchviehzucht in Deutschland kann durch die Setzung von Zuchtzielen daher Einfluss nehmen auf die Gesundheit der Hochleistungskühe. Bis zur Einführung des RZG 1997 wurde zu 100 % auf das Leistungsmerkmal Milchleistung gezüchtet. In den 1990er Jahren kamen schließlich schrittweise funktionelle Merkmale hinzu, sodass im aktuellen Zuchtwert die Milchleistung eine Gewichtung von 45 % beträgt. Dargelegte Studien zeigen, dass die in der Vergangenheit liegende Verfolgung der einseitigen produktionsfördernden Zuchtziele in der Milchviehzucht die gesundheitlichen Probleme der Hochleistungskühe verschärft haben. Eine Verbesserung der Tiergesundheit kann nur durch weitere Anpassungen und Erhöhungen der Gewichtung von Gesundheitsmerkmalen geschehen. Das aktuell formulierte Zuchtziel in Deutschland sollte für eine zukunftsfähige gesunde Kuh weniger Gewichtung auf die „wirtschaftliche Leistungskuh in milchbetontem Typ und mit hoher Milchleistung“ legen, sondern unter Nutzung der neuen molekularbiologischen Möglichkeiten in der Genetik mehr Bedeutung den funktionellen Merkmalen zukommen lassen. Denn nur eine gesunde Kuh ist auch eine für den Betrieb ökonomisch wertvolle Kuh. Die dargestellten gesundheitlichen Probleme der Hochleistungskühe haben letztlich eine Tierschutzrelevanz und gefährden das gesellschaftliche Ansehen der Nutztierproduktion. Jede (Produktions-) Erkrankung kann je nach Ausprägung und Umfang zu vermeidbaren Schmerzen, Schäden und Leiden einer Milchkuh führen. In jedem Fall kommt es zu einer Verschlechterung des Tierwohls. Nach Auslegung des Überforderungsparagrafen (§ 3 Nr. 1 TierSchG) und Qualzuchtparagrafen (§ 11 b TierSchG) können Rückschlüsse zwischen den durch die züchterisch einseitig voran getriebene Milchleistungssteigerung und den vermehrt auftretenden Produktionskrankheiten gezogen werden. Es ist gemäß § 11 b TierSchG ein Abgehen von den bisherigen Zuchtzielen zugunsten einer Selektion auf Langlebigkeit, hohe Lebensleistung, Krankheitsresistenz und flache Laktationskurven geboten. Die Anwendung und Auslegung des TierSchG ist in Deutschland eine Ermessensfrage und wird dadurch erschwert, dass Tierärzte zwar die Tiergesundheit beurteilen und eventuelle Missstände auf Grundlage des TierSchG beheben könnten, aber keine Zuständigkeit im Rahmen des Tierzuchtgesetzes in Deutschland haben. Die in diesem Review dargestellten Daten und Zusammenhänge können für die Einführung bzw. Erarbeitung einer Handlungsempfehlung, welche Grenzwerte für leistungsorientierte Zuchtziele aufzeigen könnte, dienen.
Aktualisiert: 2022-04-07
Autor:
> findR *
> Buchhandlung findr > Verlag findr > Für Buchhändler

Experimentelle Untersuchungen zum Effekt von Rationen mit einem unterschiedlichen Gehalt an strukturwirksamer Rohfaser und des Einsatzes von Natriumhydrogencarbonat auf den Säuren-Basen-Haushalt von Milchkühen

Experimentelle Untersuchungen zum Effekt von Rationen mit einem unterschiedlichen Gehalt an strukturwirksamer Rohfaser und des Einsatzes von Natriumhydrogencarbonat auf den Säuren-Basen-Haushalt von Milchkühen von Woida, Stephanie
Experimental studies on the effect of rations with different content of structurally effective raw fiber and the use of sodium hydrogen carbonate on the acid-base balance of dairy cows The feeding of high-yielding dairy cows often occurs at the interface between ensuring a demand-oriented energy supply and fulfilling a ruminant-oriented structural supply. This increasingly leads to feeding-related stress levels in the acid-base balance of the animals resulting in a negative impact on animal health. Over a period of 21 days respectively, four rumen-fistulous, lactating dairy cows were presented with a total of four different TMRs, which differed only in the chop length of the straw component used (straw meal, chop length approx. 0.2–0.5 cm; straw chop, chop length approx. 1–2 cm) and with regard to the addition of 120 g NaHCO3 per animal per day. During the 21-day study phases, rumen fluid, blood and urine samples were taken, and the feed intake was recorded in the time between feed presentation and sampling. Samples were taken daily during the first week and thereafter at intervals of three days. On days 3 and 21, additional daily examinations (5 a.m. to 5 p.m.) were conducted. The data of the monthly milk yield test was available as milk yield data. Within the test period, a shift of the acid-base balance in the acidotic direction was observed. No significant differences between the feeding groups were observed for feed intake and the parameters determined in blood and rumen fluid, except for the mean ruminal potassium concentration. In the urinary results, the groups without the addition of 120 g NaHCO3 per animal per day demonstrated an acidotic metabolic state with urinary parameters outside the reference ranges compared to the groups receiving NaHCO3 daily. The differences between the feeding groups were partly highly significant, depending on the use of NaHCO3. The rations used in this study have a negative effect on the acid-base balance of the animals, irrespective of the chop length of the straw components used. This could be mitigated by using 120 g NaHCO3 per animal per day. The results of the rumen fluid tests do not indicate any significant differences between the feeding groups. For the ration groups without the addition of NaHCO3, the diagnosis of subacute rumen acidosis in combination with the parameters of urine is correct (Staufenbiel 2011). In contrast, the ration groups with added NaHCO3 would tend to be classified as microbial rumen fermentation disorders.
Aktualisiert: 2021-10-20
Autor:
> findR *
> Buchhandlung findr > Verlag findr > Für Buchhändler

Erkennen des Beginns der klinischen Mastitis durch Auswertung der täglichen Aktivitäts- und Milchmengendaten von Milchkühen

Erkennen des Beginns der klinischen Mastitis durch Auswertung der täglichen Aktivitäts- und Milchmengendaten von Milchkühen von Weise, Susann
Detection of the start of clinical mastitis by analysing daily activity and milk yield data in dairy cows Mastitis is the disease with the highest economic impact in dairy production. As it is a multifactorial disease, different factors influence the emergence of mastitis and the clinical occurrence can be divers. Digitalization in the dairy barn, known as precision dairy farming, has the potential to serve as a syndromic surveillance system. The detection of a beginning clinical mastitis by changes in milk yield and behavior may allow early recognition and treatment of the cow at risk. In this study, individual milk yields and activity variables of holstein frisian dairy cows housed in freestall barns in two dairy farms (farm 1 hold 1100 and farm 2 hold 400 milking cows) were investigated for deviations of this variables in the days, before clinical mastitis was diagnosed. Documented mastitis events in the herd management software Dairy Comp305 were used to identify mastitis periods. The cows were equipped with activity sensors (IceQubes of IceRobotics LtD, South Queensferry, UK). First, the absolute values of daily milk yields and activity values (lying time, standing time, steps, motion index and changes of standing to lying) were examined ten days before the documented mastitis event. After that, the individual relative deviation five days before mastitis was calculated for all listed variables. Due to the indirect proportional relationship of standing time and lying time and the lack of statistical significance of changes between standing and lying concerning the development of mastitis, the number of variables were reduced to the relative deviation in milk yield, lying time and motion index. On day two before the documented mastitis, the chosen variables were significant compared to the control periods. The relative deviations of milk yield, lying time and motion index were used to distinguish between animals with mastitis and a control group. In farm 1, a combination of cut-off points led to a sensitivity of 70 % and a specificity of 40 %. In farm 2, the sensitivity of 70 % and specificity of 63.6 % was reached. When the effect of the lactation phase on the deviation in milk yield and the individual activity to the group activity was taken into account, it became evident that this was no meaningful advantage in distinguishing mastitis periods from a control periods by relative deviations. So far, no comparable number of mastitis events over such a long period was used for analysing this topic. It has to be noted however, that further analyses may be necessary, which could utilize more detailed information about clinical mastitis. It will also be important to check the insights of this thesis during the daily work in dairy farms.
Aktualisiert: 2021-06-24
Autor:
> findR *
> Buchhandlung findr > Verlag findr > Für Buchhändler

Untersuchungen zur Beurteilung der Kupferversorgung von Milchkühen

Untersuchungen zur Beurteilung der Kupferversorgung von Milchkühen von Helm, Susanne
Das Spurenelement Kupfer spielt durch seine Beteiligung an zahlreichen physiologischen Prozessen eine essentielle Rolle im menschlichen und tierischen Organismus. Zur Erhaltung der Gesundheit und der Produktivität von Milchkühen ist daher eine adäquate Zufuhr von absorbierbarem Kupfer über das Futter unabdingbar. Aufgrund der besonderen Verdauungsphysiologie von Wiederkäuern stellt die optimale Futterzusammenstellung eine nicht zu unterschätzende Herausforderung dar. Gelingt die adäquate Kupferversorgung über die Nahrung nicht, kann es zu bedrohlichen Mangelerscheinungen oder Vergiftungen kommen, die nicht nur Einzeltiere, sondern auch die ganze Herde betreffen können. Um im Verdachtsfall schnell gegensteuern zu können, sind geeignete Diagnostika zur Erkennung der Versorgungslage und das Wissen um die Besonderheiten des Kupferstoffwechsels beim Rind von großer Bedeutung. Im Fokus dieser Arbeit stand die Untersuchung der Kupferversorgung bei Milchkühen. Hierfür wurden Daten von 243 Milchviehbetrieben aus den östlichen Bundesländern ausgewertet, die zuvor im Rahmen der Bestandsbetreuung durch die Klinik für Klauentiere der FU-Berlin im Zeitraum von 2007 bis 2014 erhoben worden waren. Die Daten umfassten die Analyseergebnisse der Kupferkonzentration in Blut-, Haar-, Urin- und Kotproben von Kühen in verschiedenen Laktationsabschnitten. Die anschließende statistische Auswertung der Analyseergebnisse hatte zum Ziel, die Verteilung und das Verhalten des Spurenelements Kupfer in den einzelnen Probenmedien zu ermitteln, um daraus ihre jeweilige diagnostische Eignung zur Beurteilung des Kupferstatus bei Milchkühen abzuleiten und Referenzbereiche für eine physiologische Kupferkonzentration in den Probenmedien zu definieren. Zusätzlich wurden Zusammenhänge zwischen der Kupferkonzentration in den Probenmedien und anderen Parametern, wie den Serummesswerten anderer Mengen- und Spurenelemente, chemischen und hämatologischen Blutparametern sowie Produktions- und Fruchtbarkeitskennzahlen, untersucht. Um mögliche Einflüsse der (Jahres-)zeit, des geographischen Standorts sowie des Laktationsstadiums auf die Kupferkonzentration in den Probenmedien zu identifizieren, wurde zudem eine Varianzanalyse durchgeführt. Aus den Ergebnissen der statistischen Auswertung lässt sich schließen, dass alle Probenmedien außer Urin die Versorgungslage des Organismus mit dem Spurenelement Kupfer widerspiegeln, sie zur Diagnose einer Unter- oder Überversorgung mit Kupfer jedoch nur eingeschränkt nutzbar sind. Der Kupfergehalt im Urin bewegt sich überwiegend im niedrigen Konzentrationsbereich. Deshalb wird eine diagnostische Eignung dieses Probenmediums, Versorgungsschwankungen zuverlässig anzuzeigen, bezweifelt. Unter den Blutprobenmedien nimmt die Kupferkonzentration im Plasma die höchsten Werte an, gefolgt von Vollblut und Serum, wobei letzteres die geringste Kupferkonzentration im Blut aufweist. Die Korrelationsanalyse zeigte, dass sich ein Anstieg der Kupferkonzentration im Blut am stärksten im Plasma niederschlägt. Deshalb wird die Konzentrationsanalyse des Plasmakupfers innerhalb der Blutprobenmedien als Diagnostikum der Wahl eingestuft. Das Probenmedium Haar spiegelt den Versorgungsstatus zeitverzögert wider. Es kann daher nicht verwendet werden, um kurzfristige Versorgungsschwankungen festzustellen, wohl aber, um sich einen Überblick über die Kupferversorgung der letzten Monate zu verschaffen. Fäkale Kupferkonzentrationen spiegeln eliminiertes und nicht aus der Nahrung absorbiertes Kupfer wider. Sie können beim Verdacht auf eine alimentäre Unter- oder Überversorgung zusätzliche Hinweise liefern. Die Korrelationsanalysen zwischen der Kupferkonzentration in den einzelnen Probenmedien und hämatologischen sowie chemischen Blutparametern ergaben keine nennenswerten Zusammenhänge. Ähnlich verhielt es sich mit den Leistungs- und Produktionskennzahlen, die im Gegensatz zu den Erwartungen gar nicht oder nur äußerst schwach mit dem Kupferstatus korrelierten und deshalb zur Ableitung von Erkenntnissen nicht ausreichten. Um aussagekräftige Ergebnisse zu erhalten, müsste in einer Folgeuntersuchung das Versuchsdesign entsprechend geändert werden. Die signifikant positiven Korrelationen zwischen der Kupferkonzentration in den Blutprobenmedien und den Serummesswerten anderer Mengen- und Spurenelemente ließen auf eine gleichmäßige Zufuhr dieser Nährstoffe schließen und unterstützten die Annahme einer bedarfsgerechten Versorgung der Probanden. Die Varianzanalyse zeigte deutlich, dass der Kupferstatus von Milchkühen (jahres-)zeitlichen und geographischen Einflüssen unterliegt. So verzeichneten Kühe im vierten Quartal des Jahres die höchsten mittleren Plasmakupferkonzentrationen. Dies kann als Hinweis dafür verstanden werden, dass bei herbstlichen Temperaturen der Kuhkomfort und damit auch die Futter- und Spurenelementaufnahme steigen. Kühe aus Thüringen wiesen im Vergleich der Bundesländer den niedrigsten Kupferstatus im Plasma auf. Dies kann an niedrigeren Kupferkonzentrationen im Grundfutter oder der TMR liegen. Es kann aber auch damit zusammenhängen, dass in den übrigen Bundesländern vergleichsweise mehr Kupfer über Mineralergänzungsfutter supplementiert wird. Den Einfluss des Laktationsstadiums auf die Kupferkonzentration betreffend, lässt sich zusammenfassend feststellen, dass frischmelkende Kühe unmittelbar nach der Kalbung in allen drei Blutprobenmedien die höchste Kupferkonzentration aufwiesen. Während der Früh- und der Hochlaktation sank die Kupferkonzentration, um bei Kühen in der Vorbereiterphase den niedrigsten Wert anzunehmen. Diese wellenförmige Dynamik der Kupferkonzentration im Blut sollte in Form von getrennten Referenzbereichen für Vorbereiter, Früh- und Hochlaktationskühe auch in der Routinediagnostik berücksichtigt werden. Im Haar war die Laktationsdynamik zeitlich verschoben. Die höchste Kupferkonzentration fand sich im Haar von Hochlaktationskühen.
Aktualisiert: 2021-04-22
Autor:
> findR *
> Buchhandlung findr > Verlag findr > Für Buchhändler

Ökonomische Bewertung von Erkrankungsfällen bei Milchkühen mithilfe des herdendatenbasierten Kalkulationsmoduls „Entgangener Ertrag“

Ökonomische Bewertung von Erkrankungsfällen bei Milchkühen mithilfe des herdendatenbasierten Kalkulationsmoduls „Entgangener Ertrag“ von Metz, Sebastian
Economic assessment of cases of disease in dairy cattle using the herd data-based calculation module “Entgangener Ertrag” The company dsp-Agrosoft Gmbh markets a dairy farm management software called Herde. For this software, a module called Entgangener Ertrag is available. According to the company the purpose of the module is the estimation of the influence of diseases and culling rates on the profitability of the dairy farm (dsp-Agrosoft GmbH, 2018). The basic approach is as follows: The user chooses a disease whose economic impact he or she wants to have illustrated. The module then displays two groups of animals next to each other: animals with the diagnosis in question on the one hand and animals without the diagnosis on the other hand. The two groups’ past milk yield, reproductive parameters, cost of stock replacement and cost of cow maintenance are compared. The “Entgangener Ertrag” (loss of revenue) associated with the diagnosis is displayed. The “Entgangener Ertrag” is defined as the difference in economic outcome between the two groups. The analysis of the impact of diseases is, thus, specific to the dairy farm in question. This constitutes an essential difference to strategies that rely on information from the relevant literature in order to assess the impact of diseases. Two screenshots of the user interface are to be found in section 3.2 of this doctoral thesis. Apart from the diagnoses the fat-to-protein ratio (screening for ketotic status) and the somatic cell count (indicator for udder health) can be assessed for their economic significance. The principle of analysis is analogous to the one described above for the diagnoses. For the sake of simplicity in the following description only the terms “diseases” and “diagnoses” are used. In addition, instead of an “Entgangener Ertrag” the effect on the “Income over feedcost” can be assessed. Details on this can be found in section 4.1.5. The subject of this doctoral thesis is the critical discussion of the module described. All the corresponding remarks relate to the version of the software package described in section 3.1. The first research question is whether the module in its current version depicts the effect of a disease on the economic income of the farm in a precise enough manner to constitute a valuable decision-making support when planning investments in disease control and prophylaxis. The second goal of the thesis is to not only identify possible weak points of the module but to also elucidate what changes to the module are to be made in order to refine it with the above-mentioned scenario of application in mind. The mathematical approach of the module is described in detail. Furthermore, the results of the application of the module to real life data are described. The data stem from the backup files of the Herde-software of two German dairy farms. Subsequently, a detailed discussion of the module is undertaken, also with reference to the relevant literature on the economic effects of diseases on the parameters in question. Both fundamental conceptual problems as well as “minor technical shortcomings” in the programming are identified. Suggestions for improvement are made. When designing an economic decision-making support tool, methodical precision must be weighed against practicality and usability. In view of this, it must be taken into consideration that the identified weak points of the module in its current form differ in relevance for its overall assessment. The improvement of the presentation of the effect of a disease on the milk yield is identified as a priority in the future further development of the module. Because of the particular significance of this aspect, both the underlying problem and a possible approach to its resolution are described in some detail using the example of the diagnosis sole ulcer: Assuming that animals that, for genetic reasons, are especially high producing have an especially strong predisposition for sole ulcers (because of an especially strong mobilization of adipose tissue and therefore an especially thin digital cushion; see section 5.1.1) it must be deduced that the diagnosis sole ulcer constitutes an indirect selection criterion for animals with a high potential milk yield. It should then come as no surprise that – at least for the time period analysed here – in both dairy farms this diagnosis is largely associated with a higher milk yield. The chances are that this can be explained by a situation where the disease does in fact reduce the milk yield of the effected animal (painful standing, therefore reduced feed intake and so on) but only to an extent where the average yield of these animals is still above that of animals without sole ulcer. The actual reduction in milk yield of the diseased animal in the sense of a negative deviation from its potential – and therefore the effect of the disease – cannot be deduced. A possible approach towards an improvement of the presentation is the division of the animals into productivity groups based on their potential milk yield. Animals with/without the diagnosis could then be compared within the same productivity group. The milk yield in previous lactations could be used as an indicator for the potential yield of an animal. Some other approaches are also outlined (see section 5.1.1). The particular significance of the presentation of the association between disease and milk yield is, on the one hand, due to the large share of the milk yield in the “Entgangener Ertrag.” On the other hand, in both dairy farms analysed here the diagnosis sole ulcer is largely associated with a considerably lower culling rate. This is probably owing to a protective effect of the high milk yield rather than a direct (positive) effect of the disease, the protective effect being that the farmer is inclined to keep high yielding animals in the herd rather than culling them. The comparison of animals within the same productivity group could also improve this part of the presentation. There is yet another aspect: in both dairy farms the diagnosis sole ulcer is largely associated with a lower reproductive performance – especially when looking at the calving interval. In this case it is conceivable that this is at least in part due to a more or less direct effect of the disease. On the other hand, it cannot be ruled out that the high milk yield per se is associated with a low reproductive performance. The question of whether such an association exists is the subject of some controversy in the literature (see section 5.1.1). If it does in fact exist, then also this part of the presentation could be improved by comparing animals with/without diagnosis within the same productivity group. It is important to note, that the reasoning described above is not only valid for the diagnosis sole ulcer but rather for any disease whose incidence is associated with the level of the potential milk yield. Further room for improvement was identified in the following areas. The individual points are discussed in detail elsewhere in this thesis and therefore only mentioned briefly here: • Further aspects of the creation of the comparison groups with/without diagnosis (apart from the division into productivity groups), especially bias of the results due to nonconsideration of diagnoses other than the one chosen for analysis, are discussed. • Calculation of the cost of stock replacement in the herd: currently only those payments that are the immediate result of the culling of an animal and its replacement by a new one are considered. The change in future payments due to the change in the herd structure (net present value approach) have up until now not been taken into account. • Currently the assumed cost of cow maintenance stay the same throughout the whole lactation. The possibility of a differentiation specific to the farm in question should be considered. • The calculation of the economic effect of diseases is currently only undertaken in retrospect. Possible approaches towards also taking into consideration future effects are outlined briefly. • Associations between diseases and the two reproductive parameters (calving interval and number of portions of semen used) are generally considered in the calculation of the “Entgangener Ertrag”. This is true even for cases of disease appearing after the beginning of pregnancy. This aspect of the presentation should be reviewed. What is more, the costs of semen are systematically exaggerated due to the presumption of costs for animals that were de facto not inseminated. Both points can readily be rectified by changing the programming of the module. • In the current definition of the amount of milk it is not taken into consideration whether the milk is marketable; this means milk discarded due to the use of antibiotics is indiscriminately considered. It would be preferable to focus the presentation on marketable milk. • Various cost categories remain unconsidered in the calculus of the module until now. Weighing methodical effort on the one hand against the significance for the overall result on the other, the inclusion of treatment costs seems particularly worth considering. • Even in situations with zero cases of the diagnosis chosen for analysis a “Entgangener Ertrag” is displayed. This should be reviewed. • When the fat-to-protein ratio (screening for ketotic status) is chosen for analysis the differentiating criterion is > 1.5. The results of a recent clinical study suggest that a lower cut-off point may be more favourable. What is more, there is currently potential for misunderstanding regarding the user’s selection of the observation period. • A few minor problems or rather potential for misunderstanding in the user interface are outlined. • Alongside the calculation of the “Entgangener Ertrag” the indication of the farm-specific marginal revenue of different courses of action in the field of disease control and prophylaxis would be useful. This would constitute another decision-making support for the user of the module. In the course of a future iterative improvement of the module an assessment of the practical relevance for the functionality of the module should be undertaken for each of the points made above. A comparison of the results calculated by the respective level of development with results from the relevant literature can contribute to this. The overview of the relevant literature found in this doctoral thesis can be consulted to this end. Regarding the research questions stated above the conclusions drawn can be summarised as follows: When using the module as a decision-making support while planning investments in disease control and prophylaxis the presented “Entgangener Ertrag” must be interpreted with prudence. No universally valid statement regarding the precision of the presentation of the effect of a disease on the economic income of the farm can be made. Rather, the precision of the presentation depends decisively on the question whether the incidence of the disease chosen for analysis is associated with the potential milk yield. For the group of diseases where such an association is present it is to be expected to an especially high extent that the module does in fact depict the association between disease and average milk yield but not the actual effect of the disease. Specifically regarding the above-mentioned group of diseases, this results in a substantial limitation in the applicability of the results of the module as a direct decision-making support in the above-mentioned scenario. As described above, this conclusion results to a large extent from the generally large share of the milk yield in the “Entgangener Ertrag” but also from a presumed biasing effect on the presentation of other parameters. More details regarding these aspects and possible approaches for further improvement of the module can be found in section 5.1. Within the scope of this doctoral thesis a number of further fundamental conceptual problems of the module as well as “minor technical shortcomings” in the programming were identified, which generally deserve attention – independently from the characteristics of the disease chosen for analysis. Suggestions for improvement were made. The relevance of the individual aspects for the overall functionality of the module cannot be assessed in an objective fashion. Rather, this is up to the user to decide and will ultimately depend on his or her requirements for the module. The necessary balance between methodical precision on the one hand and practicality and usability on the other hand was discussed in section 5.1. It is crucial that the user know about the explanatory power of the module results – and about its limits – and that he or she, thus, be in a position to make an informed decision about whether or not the module results are of value in view of the particular goal of itsapplication. The observations made in this doctoral thesis can be used to both inform the user to that effect as well as to serve as a basis for a possible – and if necessary gradual − methodical improvement of the module.
Aktualisiert: 2022-12-31
Autor:
> findR *
> Buchhandlung findr > Verlag findr > Für Buchhändler

Homöopathische Behandlung akuter geburtsbedingter Erkrankungen in der frühen Puerperalphase beim Milchrind

Homöopathische Behandlung akuter geburtsbedingter Erkrankungen in der frühen Puerperalphase beim Milchrind von Simons, Julia
Homeopathic treatment of acute calving-related diseases in the early postpartum period in dairy cows Puerperium diseases are common in dairy cows after calving and treatment regimen often includes antibiotic drugs. Due to the increase in antibiotic resistances in human and veterinary medicine, antibiotic veterinary treatments are increasingly critically discussed. As an alternative to allopathic (e.g. antibiotic or NSAIDs) therapies, homeopathic treatments are already widely used in animal production. However, evidence based studies about their efficacy are still lacking. The aim of this triple-blinded, randomized and placebo controlled clinical study was to assess the efficacy of homeopathic treatments in acute calving-related diseases in early postpartum dairy cows. Between June 2013 and May 2014, 663 cows with acute calving-related postpartum diseases from a conventional dairy farm in Brandenburg were enrolled in the study. Relevant diseases were unspecific fever, retained placenta, and vulvovaginal laceration. Poor general appearance (e.g. downer cow or prolonged fever) was used as an exclusion criterion. Animals were randomly assigned to a homeopathy and a placebo group (n = 595). Towards the end of the study, a control group (n = 68) was added to the design to assess the potential placebo effect. Homeopathic preparations (remedies) were individually selected depending on the individual disease condition and according to treatment protocols of the farm. The placebo group received placebo globules. If necessary, animals from all groups were eligible to receive allopathic treatments. Data collection included general parameters (e.g. lactation number, breeding values, and milk yield), disease related parameters (e.g. number of disease and fever days), treatment related parameters (e.g. type of treatment and number of treatment days), and reproductive and culling data up to 200 days in milk. For statistical analyses, Chi-squared test, ANOVA, non-parametric tests, Kaplan-Meier curves and Cox-regression were used. Study animals in all three groups were very similar in basic characteristics, allowing the comparison among groups. There were no differences in breed, genetic potential, and milk yield in the previous lactation. Similarly, reproductive parameters (e.g. number of inseminations, time to first service, time to conception, and calving interval) and calving ease was similar among groups. An exception was the age at first calving which was significantly lower in the control group compared to the homeopathy and placebo groups. Similarly, there was a tendency for a lower lactation number in the control group. The three groups showed no difference regarding disease duration (p = 0,108), number of inseminations (p = 0,299), time to first service (p = 0,197), milk yield within the first 100 days in milk (p = 0,251) and risk of culling (p = 0,805). Furthermore, there were no differences among groups in the number of antibiotic treatments (p = 0,061) and non-antibiotic treatments (p = 0,076). The control group had a significantly reduced treatment duration in comparison with the homeopathy and placebo groups (p < 0,001), which could be attributed to a standard treatment duration of 5 days (according to the protocol) for the homeopathic and placebo treatments. Cox-regression also showed significantly shorter treatment and disease duration for control animals compared to homeopathy or placebo animals. Moreover, animals that were treated with allopathic treatments needed more time to cure compared to animals that did not receive allopathic treatments. This could be related to more severe conditions in those animals. No specific effect of homeopathic treatments used in this study could be found. An unspecific effect of the therapy was also not found. Therefore, this study does not show superiority of homeopathic therapy over allopathic or placebo treatments.
Aktualisiert: 2019-12-31
Autor:
> findR *
> Buchhandlung findr > Verlag findr > Für Buchhändler

Untersuchungen zur Versorgungslage von Milchkühen mit Aluminium, Barium und Strontium

Untersuchungen zur Versorgungslage von Milchkühen mit Aluminium, Barium und Strontium von Löbl, Sascha Scarlet
Evaluation of the aluminum, barium and strontium status in dairy cows Aluminum, barium and strontium are accidental trace elements. They have no physiological meaning for cattle. In contrast to essential trace elements, they are neither necessary for accretion and milk production nor for preserving health. However, forage (food) contains them. Therefore, they are absorbed and metabolized along other nutrients. There is no deficiency syndrome described for accidental trace elements. However, there are intoxications depicted for humans. Similar to essential trace elements, aluminum, barium and strontium posses metabolic cycles and mass balances. For these elements there is only little published regarding cattle, 90Sr* being one exception. No cattle reference values are described for aluminum, barium and strontium. The data of this work is useful for further evaluations. There are the following foci in this thesis: (1) Descriptive data analysis of the aluminum, barium and strontium concentrations in serum, plasma, whole blood, urine, hair and feces (2) Comparison of the element concentrations in different sample media (3) Evaluation of the influence of lactation status, season (quarter), year of investigation and German state on the element concentrations (4) Creation of reference values (5) Comparison of concentration ratios in various sample media from accidental and essential trace elements including sulfur The analyzed samples derive from the herd management of the Klinik für Klauentiere, Freie Universität Berlin. Therefore, randomized dairy cow herds from the newly-formed German states were chosen. Samples are pooled with a target pool size of n = 10. The pool value correspondents to the average derived from the analysis values for each single dairy cow. Each clinically healthy and multipara dairy cow is randomly chosen. They are grouped regarding lactation status (3 - 0 weeks ante partum, 0 - 1 week, 3 - 5 weeks, 15 - 18 weeks post partum; for herds < 200 cows there are different groups: 3 - 0 weeks ante partum, 0 - 5 weeks, 6 - 20 weeks post partum). 1574 serum pool samples, 1571 plasma pool samples, 1550 whole blood samples, 2019 urine pool samples, 693 hair pool samples and 79 feces pool samples were analyzed by ICP-OES (IDEXX VetMed Labor Ludwigsburg). The intra-day coefficient of variation for the concentration of the three elements in various sample media ranged from 0.7 % to 13.5 %. The inter-day coefficient of variation ranged from 0.6 % to 19.2 %. The same samples were analyzed before regarding copper, iron, zinc, selenium, manganese, molybdenum and sulfur concentrations. These analyses are part of the previously established herd management database. In this thesis they were used for the comparison of the aluminum, barium and strontium concentrations with the concentrations of essential trace elements. The statistical analyses was performed by SPSS 24 (SPSS, IBM, USA). They contain the comparison of averages by t-test for paired samples and performing of ANOVA post-hoc tests for evaluation of the effect from lactation status, year of investigation, season and German state. Furthermore, rank correlation analyses were conducted. Subsequently, reference values were estimated based on the 2.5 percentile and on the 97.5 percentile. Aluminum, barium and strontium concentrations vary strongly in various sample media (Al serum 0 - 119 μg/l, plasma 0 - 250 μg/l, urine 0 - 148 μg/l, hair 0 - 8207 μg/kg, feces 94 - 1694 mg/kg TM; Ba serum 3.4 - 48 μg/l, plasma 11 - 95 μg/l, whole blood 7.7 - 46 μg/l, urine 22 - 642 μg/l, hair 0 - 34 mg/kg, feces 24 - 93 mg/kg TM, Sr serum 37 - 306 μg/l, plasma 38 - 333 μg/l, whole blood 28 - 245 μg/l, urine 73 - 3080 μg/l, hair 0 - 29 mg/kg, feces 48 - 236 mg/kg TM). The methodology for the determination of the aluminum concentration in whole blood seems unclear. Therefore, this concentration is not suggested for further application. The factors lactation status, season (quarter), year of investigation and German state may influence significantly the results. Nevertheless, quantitative differences are only minor. Therefore, the use of uniform reference values is suitable. The analysis of concentration ratios in various sample media shows pronounced distribution differences for the accidental trace elements aluminum, barium and strontium in comparison to the essential trace elements and sulfur. Molybdenum behaves like an accidental trace element in accordance to its physiology. In conclusion, the absorption of the investigated accidental trace elements is probably passive and only minor. For avoiding intoxications absorbed aluminum, barium and strontium will be strongly eliminated by the kidneys. Clinical diagnostics of the nutritive supply status for essential and accidental trace elements is performable by the evaluation of the concentration in each forage or in the total mixed feed ration (TMR). Furthermore, the analysis of feces is suitable. The analysis of the metabolic supply status for accidental trace elements is different to the one for essential trace elements since in case of accidental trace elements only intoxications are important. Therefore, the analysis of urine samples is most suitable. Additionally, the analysis of blood samples is suitable for the determination of intoxications since there is also a high aluminum, barium and strontium concentration increase.
Aktualisiert: 2019-12-31
Autor:
> findR *
> Buchhandlung findr > Verlag findr > Für Buchhändler

Zusammenhang zwischen Tiergerechtheit und Lahmheit in neun Milchkuh haltenden Betrieben des Freistaates Sachsen

Zusammenhang zwischen Tiergerechtheit und Lahmheit in neun Milchkuh haltenden Betrieben des Freistaates Sachsen von Englisch, Annemarie Mady
Relation between animal suitability and lameness in nine dairy cow operations in Saxony, Germany One of the major challenges regarding animal welfare and economics in modern dairy farming is the high lameness prevalence in dairy cow herds. This study aimed at identifying relations between animal suitability (housing and management conditions) and lameness in dairy cows. Based on the findings, evidence-based strategies to reduce the lameness prevalence were suggested. Furthermore, the identified risk indicators were used to develop a benchmarking system for lameness across farms. The proposed system shall serve as a feasible instrument to assess animal welfare and animal suitability within the framework of the farm’s internal control as required by the German Animal Welfare Act. 605 cows from 18 housing groups (fresh cows and high yielding) of nine conventional dairy farms across Saxony, Germany, were scored for locomotion according to the five-point-scale system of Sprecher et al. (1997) during the summer period of 2013. Cows with locomotion scores 3 and higher were classified as lame. The Animal Suitability Index (German Tiergerechtheitsindex) TGI 200/1994 by Sundrum et al. (1994) as well as other environmentally-based criteria and a questionnaire were used to assess animal suitability. Out of originally 119 variables, five variables were chosen by means of a four-stage selection procedure for the univariate and multivariate statistical modelling. The relation of these variables with lameness was tested in different three-level nested logistic regression models with cow as unit of analysis. The final model consisted of four variables: type of bedding in the cubicles, cleanliness of the lying surfaces, cubicle diagonal (distance from neck rail to rear curb), and type of floor in combination with the size of the traffic area per cow. Deep bedding in cubicles was non-significantly associated with lower lameness-odds compared to rubber mats. Lying surface cleanliness scores of 3 (moderate) and 4 (clean) were associated with a significantly lower lameness risk than a cleanliness score of 2 (intermediate). When the cubicle diagonal was between 195 and 200 cm, there was a lower tendency (non-significant) for lameness than for shorter or longer cubicle diagonals. Lameness was less frequent among cows that walked on floors that were partly or completely covered by rubber mats compared to cows that walked on hard floors (concrete or asphalt). This association was significant in combination with a traffic area between 2.12 and 3.21 m² per cow. In combination with a traffic area of 4.08 to 6.90 m², there was only a non-significant tendency for no lameness. Based on these results, exemplary strategies to improve animal suitability have been suggested which can help to reduce lameness prevalence. This study combines scores of an index system, which is used for animal welfare assessment on organic farms in Germany, and other environmentally-based and management-based indicators for animal suitability in a risk analysis for lameness. The developed system can be used for the farm’s internal control as required by the German Animal Welfare Act. At the same time, it serves as a benchmarking tool for dairy farms and offers evidence-based approaches for the prevention of lameness. Further research is necessary to validate the suggested risk indicators in longitudinal studies. In addition, it should be tested in long-term interventional studies whether benchmarking and continuous follow-up can help to improve animal suitability and reduce the prevalence of lameness in dairy farms.
Aktualisiert: 2019-12-31
Autor:
> findR *
> Buchhandlung findr > Verlag findr > Für Buchhändler

Mikroarrayuntersuchung zur Beeinflussung der Genexpression in der Rinderleber nach postpartaler Propylenglycolsupplementierung

Mikroarrayuntersuchung zur Beeinflussung der Genexpression in der Rinderleber nach postpartaler Propylenglycolsupplementierung von Reisberg, Kerstin
Microarray studies on the influence of postpartum propylene glycol supplementation on gene expression in the liver of cows The aim of this study was to investigate the influence of an oral propylene glycol (PG) administration on gene expression of major metabolic pathways in the liver of dairy cows. PG has been used over decades in the prevention and therapy of bovine ketosis although its mode of action is still not understood completely. When investigating the mode of action of PG, earlier studies preferred to measure only the changes in blood concentrations of glucose, ketone bodies and other metabolites and therefore retrieved only indirect results on liver metabolism. In the present study, an Affymetrix microarray was used to investigate genome-wide gene expression in bovine liver. Fresh lactating Holstein dairy cows were randomly assigned to three treatment groups. Control group (CON), PGF1 group (300 g/day PG as total mixed ration [TMR]) or PGD (300 g/day PG as TMR and additionally 512 g PG (500 ml PG mixed into 10 l water) as Drench at d 10 post partum [pp.]). Cows received PG supplementation from day 1 until day 40 pp. They had ad libitum access to TMR and water. In the first part of the study, liver biopsies were collected from cows in CON1, PGF1 and PGD on day 10 pp. (10 cows per group; 2 hours after drenching). In the second part of this study blood samples were taken from 15 cows of a CON2 and PGF2 group on day 1, 4, 10, 20, 40, and 70 pp. for analysis of sterol concentration in the serum. Liver tissue mRNA was extracted and reverse transcribed using the Affymetrix protocol. cRNA probes were labeled, fragmented and hybridized to the bovine oligonucleotide microarray (Affymetrix). The raw data was processed and analyzed using Bioconductor and the statistical software R. The statistical analysis of predefined sets of genes showed an upregulation of genes encoding for enzymes of the cholesterol biosynthesis pathway on day 10 pp. The results from qRT-PCR experiments on the same samples verified a simultaneous up-regulation of two genes encoding for two key enzymes of the cholesterol biosynthesis (hydroxymethylglutaryl-CoA reductase and squalene monooxygenase). To prove that upregulation of genes belonging to the cholesterol synthesis pathway is functionally relevant, the concentration of cholesterol, as well as the concentrations of its precursors lanosterol and desmosterol, were measured in blood. For all three sterols, concentrations were significantly elevated after PG feeding on day 20 post partum. Stimulation of endogenous de novo synthesis can be assumed as the origin of the measured increase in serum cholesterol because the TMR was demonstrably free of cholesterol. Elevated levels of lanosterol and desmosterol also point towards an increased endogenous synthesis due to PG feeding. Cholesterol biosynthesis has never received focused attention in cattle in connection with propylene glycol feeding. Transcriptional regulation of cholesterol synthesis is in the liver of ruminants is a completely new observation and should be kept in mind when using PG as feed additive in early lactation. In humans, cholesterol synthesis is, among others, regulated by phytosterol concentration. The influence of phytosterols on cholesterol synthesis in the liver of cattle has not been investigated in detail until today. Phytosterols are common components of plants, and food of cattle contains phytosterols in high concentrations. In this study, for the first time, serum concentration of the phytosterols brassicasterol, campesterol, sitosterol and stigmasterol were measured in cattle (CON2 and PGF2). Despite the equal concentration of phytosterols in both rations, the serum concentrations of phytosterols were elevated on day 10 and 20 pp. after PG administration. This could suggest that PG not only promotes the cholesterol synthesis in liver tissue of cattle, but may also have an additional influence on sterol transport in the gut. As a conclusion, the fact that cholesterol synthesis in the liver of cattle is regulated by PG could provide an explanation for the better suitability of PG in treatment and prevention of bovine ketosis compared to other glucogenic substances. Cholesterol synthesis is on the one hand a ketone body utilizing pathway and on the other hand generates cholesterol for lipoprotein and milk fat synthesis. This study shows for the first time, that PG feeding upregulates cholesterol synthesis in the liver in a transcriptional way, the underlying mechanism of this regulation requires further investigation.
Aktualisiert: 2019-12-31
Autor:
> findR *
> Buchhandlung findr > Verlag findr > Für Buchhändler
MEHR ANZEIGEN

Bücher zum Thema dairy cows

Sie suchen ein Buch über dairy cows? Bei Buch findr finden Sie eine große Auswahl Bücher zum Thema dairy cows. Entdecken Sie neue Bücher oder Klassiker für Sie selbst oder zum Verschenken. Buch findr hat zahlreiche Bücher zum Thema dairy cows im Sortiment. Nehmen Sie sich Zeit zum Stöbern und finden Sie das passende Buch für Ihr Lesevergnügen. Stöbern Sie durch unser Angebot und finden Sie aus unserer großen Auswahl das Buch, das Ihnen zusagt. Bei Buch findr finden Sie Romane, Ratgeber, wissenschaftliche und populärwissenschaftliche Bücher uvm. Bestellen Sie Ihr Buch zum Thema dairy cows einfach online und lassen Sie es sich bequem nach Hause schicken. Wir wünschen Ihnen schöne und entspannte Lesemomente mit Ihrem Buch.

dairy cows - Große Auswahl Bücher bei Buch findr

Bei uns finden Sie Bücher beliebter Autoren, Neuerscheinungen, Bestseller genauso wie alte Schätze. Bücher zum Thema dairy cows, die Ihre Fantasie anregen und Bücher, die Sie weiterbilden und Ihnen wissenschaftliche Fakten vermitteln. Ganz nach Ihrem Geschmack ist das passende Buch für Sie dabei. Finden Sie eine große Auswahl Bücher verschiedenster Genres, Verlage, Autoren bei Buchfindr:

Sie haben viele Möglichkeiten bei Buch findr die passenden Bücher für Ihr Lesevergnügen zu entdecken. Nutzen Sie unsere Suchfunktionen, um zu stöbern und für Sie interessante Bücher in den unterschiedlichen Genres und Kategorien zu finden. Unter dairy cows und weitere Themen und Kategorien finden Sie schnell und einfach eine Auflistung thematisch passender Bücher. Probieren Sie es aus, legen Sie jetzt los! Ihrem Lesevergnügen steht nichts im Wege. Nutzen Sie die Vorteile Ihre Bücher online zu kaufen und bekommen Sie die bestellten Bücher schnell und bequem zugestellt. Nehmen Sie sich die Zeit, online die Bücher Ihrer Wahl anzulesen, Buchempfehlungen und Rezensionen zu studieren, Informationen zu Autoren zu lesen. Viel Spaß beim Lesen wünscht Ihnen das Team von Buchfindr.