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Auf der Suche nach neuen Phänotypen - Untersuchung zur Prävalenz von Schwanzveränderungen bei Milchkühen

Schubert, K.; Meier, S.; Kremer-Rücker, P. (2022)

Vortrag Jahrestagung der Deutschen Gesellschaft für Züchtungskunde 2022.

 

Vortragstagung der DGfZ und GfT am 21./22. September 2022 in Kiel

Auf der Suche nach neuen Phänotypen - Untersuchung zur Prävalenz von Schwanzveränderungen bei Milchkühen

K. Schubert, S. Meier, P. V. Kremer-Rücker1

1Hochschule Weihenstephan-Triesdorf, Markgrafenstraße 16, 91746 Weidenbach

1        Einleitung

Schwanznekrosen bei Mastbullen wurden bereits in den 1970er Jahren beobachtet und beschrieben. Diese gehen in den meisten Fällen mit einem gestörten Allgemeinbefinden, reduzierter Futteraufnahme und Gewichtsverlust einher. Bei schweren Verläufen weitet sich die Entzündung auf das Rückenmark und andere Organe aus und führt im Extremfall zum Tod durch frühzeitige Schlachtung (Drolia et al., 1991; Heers et al., 2017). Zu den Ursachen wurden bis zum aktuellen Zeitpunkt lediglich Hypothesen verfasst. Dabei werden Betonspaltenböden, mangelnde Hygiene, Trittverletzungen durch Artgenossen sowie Mykotoxine und Strukturmangel in der Ration als Einflussfaktoren angesehen (Dirksen et al., 2006; Heers et al., 2017; Metzner, 2019).  Dahingegen ist bei Milchkühen zum aktuellen Zeitpunkt die Datenlage noch gering.

2        Material und Methoden

Für die vorliegende Untersuchung wurden die Schwänze von 213 Kühen über einen Zeitraum von zehn Monaten (11.04.2021 bis 20.01.2022) untersucht. Dabei wurden Tiere ausgewählt, welche zwischen dem 01.03.2021 und dem 30.04.2021 gekalbt haben. Die Datenerhebung fand in einer ostdeutschen Milchviehherde mit 1300 Holsteinkühen, jeweils zeitgleich mit der Milchleistungsprüfung (MLP) statt. Hierfür wurden die Schwänze von allen Tieren mit Hilfe eines Tailwell2® geschoren. Im Anschluss daran erfolgte die Beurteilung der Schwänze nach dem Dairy Tail Score von Kremer-Rücker (unveröffentlicht) sowie die Lahmheitsbeurteilung nach Sprecher et al. (1997) und die Körperkonditionsbeurteilung nach Edmonson et al. (1989). Folgende Parameter flossen außerdem mit in die Datenauswertung ein: Laktationsnummer, Melktage, Milchmenge (kg/Tag), Fett-Eiweiß-Quotient (FEQ), Zellzahl (1.000 Zellen/ml), Rasse und Vater. Mit Beginn der Datenerhebung haben außerdem zwei Tinytag Datenlogger installiert und so alle dreißig Minuten Temperatur und Luftfeuchtigkeit aufgezeichnet, woraus der Temperatur-Humiditäts-Index (THI) errechnet wurde. Die statistische Analyse erfolgte mittels Chi²-Test und RStudio Version 2021.09.2.

3        Ergebnisse und Diskussion

Veränderungen traten an der Schwanzspitze selbst, aber auch im darüberliegenden Bereich des Schwanzes auf. Hierzu zählten Schuppenbildung, Achsabweichung, ringartige Veränderungen, Schwellung, haarlose bis blutige Schwanzspitzen sowie warzenähnliche Zubildungen (Abbildung 1). Von den insgesamt 213 Einzeltieren im Versuch gab es kein Tier, welches über den gesamten Beobachtungszeitraum frei von Schwanzveränderungen war.

 

Abbildung 1: Arten von Schwanzveränderungen. A: leichte Schuppenbildung und Achsabweichung, B: starke Schuppenbildung, C: Warzenähnliche Zubildung, D: haarlose Ringe, E: Ringeinschnürung, F: blutiger Ring, G: haarlose, geschwollene Schwanzspitze, H: geschwollene, nekrotische Schwanzspitze

Für die Veränderung „Schuppen“ konnte im Versuch die größte Prävalenz (51,95 %) ermittelt werden, während „Verdünnungen“ am seltensten vorkamen (0,19 %). Gleichzeitig war der Bereich 15 bis 20 cm oberhalb der Schwanzspitze am häufigsten (41,57 %) von Veränderungen betroffen. Die Prävalenz von Schuppen war in der ersten Laktation (P < 0,05) und im ersten Laktationsdrittel (P < 0,01) am größten und nahm mit steigender Tagesleistung zu (P < 0,05). Gleichzeitig traten Schuppen vermehrt bei einem FEQ unter 1 und über 2 auf (P < 0,05). Dahingegen kamen Ringartige Veränderungen mit steigendem Laktationstag (P < 0,01) häufiger vor. Schwellungen gingen mit steigender BCS-Note zurück (P < 0,01) und wurden in der ersten Laktation am seltensten erfasst. Allerdings stieg deren Prävalenz bei einer somatischen Zellzahl ≥ 800.000 Zellen/ml (P = 0,05). Des Weiteren bestand ein statistisch signifikanter Zusammenhang zwischen Schwanzveränderungen und der Rasse sowie des Vaters der Tiere, was auf einen genetischen Einfluss schließen lässt.

Schuppen oder Hyperkeratosen wurden bei Mastbullen ebenfalls verzeichnet. Hier treten diese zu Beginn der Veränderung auf (Drolia et al., 1991; Hofmann, 2005; Dirksen et al., 2006; Ural et al., 2007; Kordowitzki, 2015; Salib und Farghali, 2016; Freitag et al., 2017; Metzner, 2019). Dabei erscheinen Schuppen dann, wenn die Haut und deren umliegendes Gewebe nicht mehr vollumfänglich durchblutet wird. Je länger dieser Zustand anhält, umso schlechter wird die Haut mit Nährstoffen versorgt, was schlussendlich zu einer Nekrose führt (Drolia et al., 1991; Kordowitzki, 2015). Dahingegen gehören Schwellungen zu den klassischen Entzündungszeichen und gehen mit einer Erweiterung der Blutgefäße in Folge der unspezifischen Immunabwehr einher (Reiner, 2015). Mastbullen wiesen dieses Merkmal ebenfalls auf, wobei die Autoren den Grund hierfür in einer Infektion bereits verletzter Haut sehen (Dirksen et al., 2006; Thomson et al., 2007; Salib und Farghali, 2016). Beim Schwein wurden jedoch Entzündungsanzeichen am Schwanz erfasst, obwohl die betroffenen Tiere eine nachweislich unverletzte Epidermis hatten. Die Autoren sehen dies als Hinweis auf eine endogene Erkrankung an (Reiner et al., 2021). Beim Rind wird auch der Einfluss von Endotoxinen, resultierend aus Pansenacidosen, diskutiert (Freitag et al., 2017; Heers et al., 2017). So ruft bei Milchkühen ein zu geringer Strukturanteil in der Ration, gepaart mit dem Energiedefizit und Stress in der Transitphase klinische und subklinische Pansenacidosen hervor (Wilken, 2003; Heers et al., 2017; Stein, o. D.). Sinkt daraufhin der pH-Wert im Pansen sterben gram-negative Bakterien der Pansenflora ab, wodurch Lipopolysaccharide (LPS) als Zerfallsprodukt zurückbleiben (Monteiro und Faciola, 2020). Befinden sich LPS im Blutkreislauf, lösen diese eine Immunantwort mit Entzündungsreaktion im Körper aus. Um einer weiteren Ausbreitung der LPS entgegenzuwirken werden die Kapillaren im Gewebe verschlossen (Reiner, 2015). Die reduzierte Durchblutung führt jedoch sowohl bei Schweinen als auch bei Rindern zu Schwanznekrosen (Harlizius und Hennig-Pauka, 2014; Reiner, 2015, Heers et al., 2017; Stein, o.D.). Ferner wird das Allgemeinbefinden betroffener Tiere gestört, was wiederum eine reduzierte Futteraufnahme und Leistungseinbruch zur Folge hat (Wilken, 2003). Diese Studie liefert daher Hinweise, dass sich das Schwanzende von Kühen als neuer Phänotyp zur Bewertung und zur züchterischen Verbesserung der Tiergesundheit bei Kühen eignen könnte.

 

4        Literatur

Dirksen, G., Gründer, H., Stöber, M. (2006): Innere Medizin und Chirurgie des Rindes, 5. Auflage, unveränderter Nachdruck der 4. Auflage, Parey in MVS Medizinverlage Stuttgart GmbH & Co. KG, Oswald-Hesse-Str. 50, D-70469 Stuttgart.

Drolia H., Luescher, U. A., Meek, A. H., Wilcock, B. P. (1991): Tail tip necrosis in Ontario beef feedlot cattle, Can Vet J, 32:23 – 29.

Edmonson, A. J., Lean, I. J., Weaver, L. D., Farver, T., Webster, G. (1989): A Body Condition Scoring Chart for Holstein Dairy Cows, J Dairy Sci 72, 1:68-71.

Freitag, M., Heers, P. A., Beune, H. (2017): Schädigt falsche Fütterung die Schwanzspitzen? top agrar, 9/2017, 26-28.

Harlizius, J., Hennig-Pauka, I. (2014): Farbatlas Schweinekrankheiten. Eugen Ulmer KG, Wollgrasweg 41, 70599 Stuttgart (Hohenheim).

Heers, P., Beune, H., Freitag, M. (2017): Schwanzspitzennekrosen, Weil sich die Mastbullen bei enger Haltung auf den Schwanz treten? AVA Haupttagung 2017, in Nutztierpraxis Aktuell, 84 – 88.

Hofmann, W. (2005): Rinderkrankheiten – innere und chirurgische Erkrankungen, 2. Auflage, Eugen Ulmer KG, Wollgrasweg 41, 70599 Stuttgart (Hohenheim).

Kordowitzki, P. (2015): Untersuchungen zum Auftreten der Schwanzspitzennekrose bei Mastbullen. Inaugural-Dissertation, Freie Universität Berlin.

Kremer-Rücker, P. V. (2021): Dairy Tail Score. Persönliche Mitteilung.

Metzner, M. (2019): Schwanzspitzennekrose / Schwanzspitzenentzündung. Klinik für Wiederkäuer, Ludwig-Maximilians-Universität München, URL: https://www.rinderskript.net/skripten/b7-1.html (abgerufen am 16.02.2022).

Monteiro, H. F., Faciola, A. P. (2020): Ruminal acidosis, bacterial changes, and lipopolysaccharides. J Anim Sci, 98, 8:1–9.

Reiner, G. (2015): Krankes Schwein – kranker Bestand. Eugen Ulmer KG, Wollgrasweg 41. 70599 Stuttgart (Hohenheim).

Reiner, G., Kühling, J., Löwenstein, F., Lechner, M., Becker, S. (2021): Swine Inflammation and Necrosis Syndrome, (SINS). Animals, 11, 1670.

Salib, F. A. und Farghali. H. A. (2016): Epidemiological, therapeutic and surgical studies on Tail necrosis in Egypt. Inter J Vet Sci, 5/2: 58-6

Sprecher, D. J., Hostetler, D. E., Kaneene, J. B. (1997): A lameness scoring system that uses posture and gait to predict dairy cattle reproductive performance, Theriogenology 15;47(6): 1179-87

Stein, M. (o. D.): Endotoxine: Ein Problem von ungeahnter Tragweite. Fakten für die Tierproduktion von Boehringer Ingelheim. URL: https://www.tiergesundheitundmehr.de/endotoxine.pdfx (abgerufen am 15.04.2022)

Thomson, D. U., Taylor, W., Noffsinger, T., Christopher, J. A., Wileman, B. W., Ragsdale, J. (2009): Case Report – Tail Tip Necrosis in a Confined Cattle Feeding Operation. The Bovine Practitioner, 43, 1:18-22.

Ural, K., Alic, D., Karakurum, M. C., Aktas, M. S., Haydardedeoglu, A. E., Cingi, C. C. (2007): Tail-Tip Necrosis in Beef an Dairy Cattle: A Report of Seven Cases in Ankara. Kafkas Üniv Vet Fak Derg, 13 (2):203-207.

Wilken, H. (2003): Endotoxin-Status und Antioxidative Kapazität sowie ausgewählte Stoffwechselparameter bei gesunden Milch- und Mutterkühen. Inaugural-Dissertation. Veterinärmedizinische Fakultät der Universität Leipzig.


Analyse der bei Deutschen Holstein Kühen mit Schwanzläsionen assoziierten Kandidatengene

Volkert, L.; Meier, S.; Schubert, K.; Kremer-Rücker, P. (2022)

Vortrag Jahrestagung der Deutschen Gesellschaft für Züchtungskunde 2022.

 

 


Vortragstagung der DGfZ und GfT am 21./22. September 2022 in Kiel

 

Analyse der bei Deutschen Holstein Kühen mit Schwanzläsionen assoziierten Kandidatengene

L. Volkert, S. Meier, K. Schubert, P.V. Kremer-Rücker1

 

1Fakultät Landwirtschaft, Lebensmittel und Ernährung, Hochschule Weihenstephan-Triesdorf, 91746 Weidenbach

1        Einleitung

Verschiedene Aspekte des Tierwohls rücken seit einiger Zeit mehr und mehr in den Fokus. Zahlreiche neue und alte Label sollen die Transparenz im Markt für den Verbraucher in Bezug auf das Wohlergehen der Tiere erhöhen. Hierzu zählt inzwischen auch die Kennzeichnung der Haltungsform.  Gerade die Laufstallhaltung beim Milchvieh mit allen Vor- und Nachteilen wird in Zukunft eine wichtige Rolle spielen. Ein bereits lange beschriebenes Problem auf perforierten Böden mit frei laufenden Tieren sind. Schwanzspitzennekrosen. Diese treten z.B. bei Masttieren häufiger auf Vollspaltenböden als in der Anbindehaltung auf (Kordowitzki, 2015). Bei eigenen Untersuchungen an Milchrindern zeigte sich jedoch, dass Veränderungen der Schwänze auch bei diesen Tieren ein häufiges Problem darstellen. Neben den bekannten, entzündlichen Läsionen der Schwanzspitze, konnte eine Vielzahl von unterschiedlichen Veränderungen beobachtet werden (Meier et al., 2021). Laut Literatur spielen als Ursache von Schwanzläsionen Haltungsbedingungen, Haltungsform, Besatzdichte, Management und der Umgang mit dem Tier eine Rolle (Kordowitzki, 2015). Häufig als ursächlich beschrieben werden außerdem Mykotoxine. Dabei wird zwischen dem von Mutterkorn-Alkaloiden ausgelöstem Ergotismus und durch nicht weiter definiertes pilzbelastetes Futter ausgelöste Erkrankungen wie fescue foot oder Deg Nala Disease unterschieden (Cowan, 2020; Rahimabadi et al., 2022). Als dritte potenzielle Ursache kommt die Fütterung in Frage (Freitag et al., 2017). Dabei wird ein ähnlicher Pathomechanismus wie bei SINS (Swine Inflammation and Necrosis Syndrome) vermutet: Acidosen im Pansen oder Dickdarm führen zu einer massenhaften Vermehrung gram (-) Bakterien, die wiederum Lipopolysaccharide (LPS) freisetzen. Diese gelangen durch ein geschwächtes Epithelgewebe in die Blutbahn und sorgen in feinen Blutgefäßen für Durchblutungsstörungen (Plaizier et al., 2012).

Ziel der Arbeit war es herauszufinden, ob bei zuvor in Bezug auf Veränderungen des Schwanzes phänotypisierten Deutsch Holstein Kühen genetische Unterschiede bestehen und diese eventuell Hinweise auf eine der potenziellen Ursachen liefern können.

2        Material und Methoden

Für die Studie wurden 167 Deutsche Holstein Kühe in Bezug auf die Merkmalskomplexe  1) Schwanzspitzenentzündungen und -nekrosen, 2) Ringartige Veränderungen, 3) Hyperkeratosen, 4) Schwellungen, 5) Verdünnungen, 6) Achsabweichungen, 7) Warzenähnliche Zubildungen untersucht und binär bewertet. Der Genotyp wurde bei 118 Tieren über den Illumina EuroG10k (V5, V7, V8), ein SNP-Chip mit 7k bzw. 10k SNP-Analysepunkten, erfasst und bei 51 Kühen mit dem lllumina EuroG_MD (V1, V1.1, V2). Dieser SNP-Chip erlaubt die Analyse von 45k SNPs, während die Daten der 118 Kühe auf 45.613 SNPs mittels FImpute (Gene Set Enrichment Analysis) imputiert wurden. Für jedes der oben genannten Merkmale wurde separat eine genomweite Assoziationsstudie (GWAS) mittels der Software GEMMA (Zhou & Stephens, 2014) durchgeführt. Innerhalb des univariaten linearen gemischten Modells wurde eine standardisierte Verwandtschaftsmatrix verwendet, die anhand der SNP-Marker berechnet wurde und somit die Populationsstratifikation berücksichtigte. Die Laktation (1., 2., ≥3.) wurde als Kovariate betrachtet. Die Genotyp-Matrix wurde zudem im Modell verwendet und die daraus resultierenden SNP-Effekte wurden mittels Likelyhood-ratio-Test auf Signifikanz geprüft. Die genomweite Signifikanzschwelle von α = 0,05 wurde bei einem -log10(p)-Wert von 5,91 erreicht. Da es sich um eine kleine Stichprobe handelt wurden die Top-Marker bereits ab -log10(p) ≥ 3,5 weiterer Betrachtung unterzogen. Dabei wurde jeweils der höchste Wert unter den einzelnen GWAS für einen SNP herangezogen. In der Linkage Disequilibrium decay Analyse (Laido et al., 2014) wurde ein r² > 0,6 im Abstand von 325 kbp festgestellt. Dieser Abstand wurde zur Kandidatengenanalyse (Positionelle Kandidatengene) verwendet. Die Analyse der Kandidatengene erfolgte auf ENSEMBL (http://oct2018.archive.ensembl.org/Bos_taurus/) mit dem hinterlegten Referenzgenom Bos taurus UMD3.1. Die Kandidatengene wurden auf gemeinsame Funktion in der Zelle und im Organismus mittels Genontologie-Analyse (GO-Analyse) über g:Profiler (https://biit.cs.ut.ee/gprofiler/gost) und String (https://string-db.org) durchgeführt.

Einzelne GOen wurden ausgewählt und alle dazu zugeordneten Gene wurden auf deren Funktion in der Zelle und im Organismus überprüft. Hier wurde auch auf Studien anderer Tierarten und des Menschen zurückgegriffen. Zuletzt wurden die oben genannten SNPs mit ihrem Untersuchungsfenster in der AnimalQTLdb (https://www.animalgenome.org/cgi-bin/QTLdb/BT/index) auf bekannte QTL untersucht. Beachtet wurden dabei nur Merkmale, die nicht das Exterieur, die Milchleistung/-inhaltsstoffe oder Fruchtbarkeitskennzahlen beschreiben.

3        Ergebnisse und Diskussion

Über alle sieben Merkmale fanden sich 92 zu analysierende Marker damit 682 zugeordnete Gene bzw. 562 Kandidatengene. Beim Merkmal „Verdünnung“ konnten mit 24 SNPs mit -log10(p) ≥ 3,50 die meisten SNPs für die Kandidatengenanalyse festgestellt werden. Zwei Marker für dieses Merkmal überschreiten die genomweite Signifikanzschwelle.

Auf BTA5 liegt rs41618168, mit einem Wert von 6,40 für -log10(p). Mit ihm konnte Kandidatengen ADAMTS20 und die Merkmale Zellzahl, Zwillingsgeburten, Trockenmasseaufnahme und Reaktion auf Parasitenbefall über den QTL-Abgleich in Verbindung gebracht werden. Das Gen ist für Fruchtbarkeitsprobleme beim Menschen bekannt. May et al. (2022) untersuchten die Erstlaktationsdaten von ca. 14800 HF Kühen in Ostdeutschland auf Fruchtbarkeitsstörungen. ADAMTS20 ist in dieser Untersuchung ein Kandidatengen für Endometritis des dritten Schweregrads.

Auf BTA1 liegt rs42577957 mit -log10(p) = 9,43, es konnte das Kandidatengen TBL1XR1 und die Merkmale Hitzestress und Länge des produktiven Lebens über den QTL-Abgleich mit ihm in Verbindung gebracht werden. TBL1XR1 konnte als einzelnes Gen ebenfalls mit Hitzestress bei HF Kühen und anderen Wiederkäuern assoziiert werden (Carabaño et al., 2016).

Durch die GO-Analyse über g:Profiler wurden 23 GO und über String 20 GO in den gleichen Kategorien ermittelt. Über beide Plattformen konnte die GO „lipopolysaccharid binding“ (LPS Bindungsvermögen) identifiziert werden. Die hier gehäuft auftretenden Gene gehören zur Familie der Cathelicidine und werden in der vorliegenden Studie mit dem Marker rs109960160, auf Chromosom 22 und mit dem Merkmal Schwellung assoziiert. Cathelicidine zeigten bei Rindern Wirkung gegen Bakterien, Viren und Parasiten und sind in der Lage Lipopolysaccharide (LPS) zu binden und damit deren Wirkungen zu unterbinden (Flores, 2011). Diese Gruppe ist somit ein Teil der Immunantwort und wird auch in vielen Studien mit Mastitiden in Verbindung gebracht. LPS sind Membranbestandteile von gram (-) Bakterien, die sich z.B. bei einer Pansenacidose stark vermehren können. Dies stellt einen potenziellen Zusammenhang zwischen Fütterung und Veränderungen am Rinderschwanz dar.

Tomasinsig et al. (2010) konnten die antimikrobielle Wirkung von Cathelicidinen in vitro bestätigen. Überprüft wurden Vergleichsstämme und Isolate aus Mastitisfällen und damit die Erreger: E. coli, K. pneumoniae, S. aureus, S. epidermidis, Sc. uberis und Sc. agalactiae. Zanetti (2005) gibt einen Überblick über die große Bandbreite von Mikroorganismen, die laut verschiedener Studien durch Cathelicidine bekämpft und abgetötet werden. Dabei wird betont, dass Ergebnisse in vitro aufgrund des komplexen Zusammenspiels verschiedenster Proteine im Organismus oftmals anders ausfallen als die Ergebnisse in vivo. Welche Funktionsweisen der antimikrobiellen Wirkung, besonders gegen gram (-) Bakterien, verwendet werden, zeigen Young-Speirs et al. (2018) in einem Review auf. Dabei ist die amphiphile Natur der Cathilicidine besonders wichtig, da Membranen gram (-) Bakterien selbst auch aus amphiphilen Molekülen aufgebaut sind und so gute Reaktionspartner sind.

Insgesamt bieten die analysierten Gene einen Anhaltspunkt dafür, dass genetische Unterschiede einen Einfluss auf Veränderungen der Schwanzspitze haben. Das Krankheitsbild ist zwar nicht geklärt, aber durch die Ergebnisse dieser Arbeit sollten bei weiteren Untersuchungen LPS, Cathelicidine, ADAMTS20 und TBL1XR1 mit betrachtet werden.

4        Literatur

Carabaño, M.J., Ramón, M., Díaz, C., et al. 2016: Breeding for resilience to heat stress effects: A comparison across dairy ruminant species. Journal of Animal Science 94 (Suppl_5), 195, DOI: 10.2527/jam2016-0402, Abstract.

Cowan, V.E. 2020: Investigation of the subclinical toxicological effects of ergot alkaloid mycotoxin (Claviceps purpurea) exposure in beef cows and bulls. University of Saskatchewan, Dissertation.

Flores, E.G. 2011: Characterization of the bovine cathelicidin gene family. Texas A&M University ProQuest Dissertations Publishing, UMI 3486189, Dissertation.

Freitag, M., Heers, P.A., Beune, H. 2017: Schädigt falsche Fütterung die Schwanzspitzen?. top agrar 9/2017, R26–R28.

Kordowitzki, P. 2015: Untersuchungen zum Auftreten der Schwanzspitzennekrose bei Mastbullen. Freie Universität Berlin, Dissertation, DOI: 10.17169/refubium-15478 .

Laido, G., Marone, D., Russo, M.A., et al. 2014: Linkage Disequilibrium and Genome-Wide Association Mapping in Tetraploid Wheat (Triticum turgidum L.). PLoS ONE 9(4), 1–18, DOI: 10.1371/journal.pone.0095211 .

May, K., Sames, L., Scheper, C., König, S. 2022: Genomic loci and genetic parameters for uterine diseases in first-parity Holstein cows and associations with milk production and fertility. Journal of Dairy Science 105 (1), 509–524, DOI: 10.3168/jds.2021-20685 .

Meier, S., Abel, K., Kremer-Rücker, P.V. 2021: Development of a Tail Scoring as Health Indicator for Dairy Cows. Proceedings of the 44th ICAR Annual Conference virtually held from Leeuwarden, NL 2021 (25), 1-16.

Plaizier J.C., Khafipour E., Li S., et al. 2012: Subacute ruminal acidosis (SARA), endotoxins and health consequences. Animal Feed Science and Technology 172 (1-2), 9–21, DOI: 10.1016/j.anifeedsci.2011.12.004 .

Rahimabadi, P.D., Yourdkhani, S., Golchin, D., Rad, H.A. 2022: Ergotism in feedlot cattle: clinical, hematological, and pathological findings. Comparative Clinical Pathology 31 (2), 281–291, DOI: 10.1007/s00580-022-03331-7 .

Tomasinsig, L., De Conti, G., Skerlavaj, B., et al. 2010: Broad-Spectrum Activity against Bacterial Mastitis Pathogens and Activation of Mammary Epithelial Cells Support a Protective Role of Neutrophil Cathelicidins in Bovine Mastitis. Infection and Immunity 78 (4), 1781–1788, DOI: 10.1128/IAI.01090-09 .

Young-Speirs, M., Drouin, D., Cavalcante, P.A., et al. 2018: Host defense cathelicidins in cattle: types, production, bioactive functions and potential therapeutic and diagnostic applications. Review. International Journal of Antimicrobial Agents 51 (6), 813–821, DOI: 10.1016/j.ijantimicag.2018.02.006 .

Zanetti, M. 2005: The Role of Cathelicidins in the Innate Host Defenses of Mammals. Current Issues in Molecular Biology 7 (2), 179–196, DOI: 10.21775/cimb.007.179 .

Zhou, X., Stephens, M. 2014: Efficient multivariate linear mixed model algorithms for genome-wide association studies. Nature Methods 11 (4), 407–409, DOI: 10.1038/nmeth.2848 .


Regular milking within natural suckling behavior interval minimizes differential somatic cell count in dairy cows milked by automatic milking systems

Kremer-Rücker, P.; Meier, S. (2022)

2022, Abstract No. 1268.

 

Objectives
Somatic cell count (SCC) is a reliable and approved parameter for the estimation of udder health. The main
cell types regarding somatic cells in the udder are lymphocytes, macrophages, and polymorph nuclear
leucocytes (PMN). The differential somatic cell count (DSCC) represents the proportion of lymphocytes and
PMN to total SCC, the remaining percentages to SCC are macrophages. So far, the effects of milk yield,
season, parity, milking frequency, days in milk, and major pathogens on the DSCC are already described. A
further known effect on udder health and SCC is the milking interval (MI). On farms with automatic milking
systems (AMS) the MI can vary for each cow compared to conventional milking systems. Regarding DSCC
and SCC, cows milked by AMS systems showed higher values compared to cows milked by conventional
milking systems. Therefore, the aim of this study was to evaluate the effect of MI on DSCC.
Materials and methods
Data from 27 dairy herds from Germany including 6,500 dairy cows and 43,229 recordings were evaluated.
The data resulting from milk yield performance testing were collected between January to December 2020. All
herds used automatic milking systems combined with free cow traffic. Milk yield performance testing data was
recorded 11-times per year on each farm and included the DSCC measured using the FOSS method
described by Damm et al. (2017). Date and time from each milking at the farms were available and used to
calculate each individual MI between milkings. MI ranged from 1 h minimum to 24 h maximum. Data of milking
interval >24 h were excluded. Means were compared using Wilcoxon test. P-values were Bonferroni adjusted;
the threshold for significance was set after adjusting to α < 0.05. A linear mixed model was used to estimate
the effect on DSCC including MI, milk yield, lactation, days in milk, and season as fixed effects and herd,
individual cow, and residuals as random effects.
Results
Mean MI was 10.6 h (±0.04 h SE). MI of ≤4 h resulted in the highest DSCC (52.3 ±1.0%). The DSCC
decreased significantly for cows showing a MI >4 and ≤6 h (39.0 ±0.6%) and had its minimum between MI >6
and ≤8 h (37.9 ±0.4%). MI between >8 - ≤10 h resulted in a DSCC of 40.5% (±0.4%). The DSCC increased for
MI >10 - ≤12 h and for >12 h MI (42.8 ±0.4%; 46.6 ±0.3%, respectively; all P-values < 0.001). Therefore, the
most frequently milked cows showed higher DSCC compared to cows between 4 and 8 hours MI. Considering
natural behavior, the suckling interval of calves from their mothers ranges between 4 to 6 times per day, which
results in a MI of 6 to 4 hours, representing the MI of the second lowest DSCC found in this dataset.
The standard deviation of the MI (MISD) expresses the irregularity of milkings. Data evaluation showed the

lower the MISD, the lower the DSCC. For MISD ≤2 h the DSCC was lowest (38.8 ±0.7%), compared to MISD >2
- ≤4 h (41.0 ±0.5%), MISD >4 - ≤6 h (43.2 ±0.7%), and MISD >6 h (48.1 ±1.1%). Irregular milking is also known
to impair udder health and increase the SCC of cows.
Conclusions
Milking interval between 4 to 8 hours minimizes DSCC, which aims the natural MI of suckling calves. A more
regular milking interval in AMS farms could reduce DSCC and therefore improve udder health. AMS farms
should strive their management and settings of the AMS to encourage cows to visit the AMS more regularly.
Acknowledgement
We kindly acknowledge the QNETICS GmbH, Erfurt, Germany, for providing the dataset of DSCC values and
milk yield recording data for this study.


Genome-wide association study for tail alterations in German Holstein dairy cows

Kremer-Rücker, P.; Schubert, K.; Meier, S. (2022)

2022, Abstract No. 1229.

 

Objectives
Tail injuries and pathological alterations have been reported in many species. In cattle, they were investigated
mainly in fattening bulls and feedlot cattle. In dairy cows high prevalences for different tail alterations were
found. However, aetiology and pathogenesis of this health trait are still unclear and need further investigation.
Out of 4443 phenotypes of different tail alterations we assorted seven groups common in dairy cows: 1. very
tip of the tail , 2. ring-like, 3. scurf, 4. swelling, 5. thinning, 6. axis anomaly, and 7. verruca-like mass. The
objective of this study was to identify genomic regions that may influence the occurrence of different tail
alterations in dairy cows, which could be useful for a potential implementation of a genomic selection tool for
more robust and healthy cows in the future.
Material and methods
Occurrence data of each tail alteration group were collected monthly from 167 German Holstein cows. The
cows originated from a German 1300 cows dairy herd. Data collection was performed from May to December
2021, since calving of all included cows was from April to May. The cows were in their first to seventh lactation.
The phenotype was encoded binary, where 0 means the absence and 1 the presence of a tail alteration group
within the whole timespan.
For 118 cows, Illumina EuroG10k genotypes were available and imputed up to 45k (FImpute). The remaining
cows were genotyped with the Illumina EuroG MD (V1, V1.1, V2) with 45613 SNPs. After quality check (only
segregating SNPs, at least two groups with a minimum of 10 observations, no duplicated markers, a minor
allele frequency of 1%, and within Hardy-Weinberg-Equilibrium P>0.01), 41062 SNPs remained.
A genome-wide association study was performed using the software GEMMA and the univariate linear mixed
model. Each tail alteration group was treated as a separate phenotype. A standardized relatedness matrix was
included in the model and calculated on SNP chip data to consider the population stratification, since many
half-sib groups were present. The lactation (1st, 2nd, ≥3rd) was included as covariate. The genotype matrix was
included in the model and the effect size per marker was estimated and tested for significance using a Wald
test.
For positional candidate gene analysis, genomic regions around top markers (P < 0.0001) of 325kbp wereconsidered,since the linkage disequilibrium decay analysis gave a mean r² of >0.61 within this distance. The
marker positions are given on the ARS-UCD 1.2 Bos taurus genome assembly.
Results
In total 51 top markers resulted for all seven tail alteration groups, whereof one marker reached Bonferronicorrected
genome-wide significance threshold for tail alteration group “thinning” (BTA1: rs42577957, −log10(P)
= 9.22). The markers were found on 18 different chromosomes. Close to these markers, 65 positional
candidate genes reside. Among them CCDC122 (rs42421906, −log10(P) = 5.46), which was associated with
the phenotype “scurf” in our analysis. CCDC122 is one of the top differentially expressed genes in liver
metabolism in pigs showing swine inflammation and necrosis syndrome (Ringseis et al., 2021). This syndrome
results in severe tail alterations in pigs as well.
Conclusions
This first genetic investigation of tail alterations in dairy cows showed the potential of finding genetic markers
for this novel health trait. Nonetheless, it is recommended to increase the sample size of cows and to further
investigate the cause of tail alterations, to substantiate the reported phenotypes.

Literature

Ringseis, R., Gessner, D. K., Loewenstein, F., Kuehling, J., Becker, S., Willems, H., et al. (2021). Swine inflammation and necrosis syndrome is associated with plasma metabolites and liver transcriptome in affected piglets. Animals 11, 1–14. doi:10.3390/ani11030772

Sargolzaei, M., Chesnais, J. P., and Schenkel, F. S. (2014). A new approach for efficient genotype imputation using information from relatives. BMC Genomics 15. doi:10.1186/1471-2164-15-478

Zhou, X., and Stephens, M. (2014). Efficient Algorithms for Multivariate Linear Mixed Models in Genome-wide Association Studies. Nat Methods 11, 407–409. doi:10.1038/nmeth.2848

Acknowledgement
We thank the MASTERRIND GmbH, Verden, Germany, for providing the genotypes from the investigated
cows.
Funding
Part of the data results from the project TINCa Dairy, which is funded by the Tönnies Forschung, Rheda,
Germany.

more

Regular milking within natural suckling behavior interval minimizes differential somatic cell count in dairy cows milked by automatic milking systems

Kremer-Rücker, P.; Meier, S. (2022)

Proceedings of the 31. World Buiatric Congress 2022, Abstract No. 1268.

 

Objectives
Somatic cell count (SCC) is a reliable and approved parameter for the estimation of udder health. The main
cell types regarding somatic cells in the udder are lymphocytes, macrophages, and polymorph nuclear
leucocytes (PMN). The differential somatic cell count (DSCC) represents the proportion of lymphocytes and
PMN to total SCC, the remaining percentages to SCC are macrophages. So far, the effects of milk yield,
season, parity, milking frequency, days in milk, and major pathogens on the DSCC are already described. A
further known effect on udder health and SCC is the milking interval (MI). On farms with automatic milking
systems (AMS) the MI can vary for each cow compared to conventional milking systems. Regarding DSCC
and SCC, cows milked by AMS systems showed higher values compared to cows milked by conventional
milking systems. Therefore, the aim of this study was to evaluate the effect of MI on DSCC.
Materials and methods
Data from 27 dairy herds from Germany including 6,500 dairy cows and 43,229 recordings were evaluated.
The data resulting from milk yield performance testing were collected between January to December 2020. All
herds used automatic milking systems combined with free cow traffic. Milk yield performance testing data was
recorded 11-times per year on each farm and included the DSCC measured using the FOSS method
described by Damm et al. (2017). Date and time from each milking at the farms were available and used to
calculate each individual MI between milkings. MI ranged from 1 h minimum to 24 h maximum. Data of milking
interval >24 h were excluded. Means were compared using Wilcoxon test. P-values were Bonferroni adjusted;
the threshold for significance was set after adjusting to α < 0.05. A linear mixed model was used to estimate
the effect on DSCC including MI, milk yield, lactation, days in milk, and season as fixed effects and herd,
individual cow, and residuals as random effects.
Results
Mean MI was 10.6 h (±0.04 h SE). MI of ≤4 h resulted in the highest DSCC (52.3 ±1.0%). The DSCC
decreased significantly for cows showing a MI >4 and ≤6 h (39.0 ±0.6%) and had its minimum between MI >6
and ≤8 h (37.9 ±0.4%). MI between >8 - ≤10 h resulted in a DSCC of 40.5% (±0.4%). The DSCC increased for
MI >10 - ≤12 h and for >12 h MI (42.8 ±0.4%; 46.6 ±0.3%, respectively; all P-values < 0.001). Therefore, the
most frequently milked cows showed higher DSCC compared to cows between 4 and 8 hours MI. Considering
natural behavior, the suckling interval of calves from their mothers ranges between 4 to 6 times per day, which
results in a MI of 6 to 4 hours, representing the MI of the second lowest DSCC found in this dataset.
The standard deviation of the MI (MISD) expresses the irregularity of milkings. Data evaluation showed the

lower the MISD, the lower the DSCC. For MISD ≤2 h the DSCC was lowest (38.8 ±0.7%), compared to MISD >2
- ≤4 h (41.0 ±0.5%), MISD >4 - ≤6 h (43.2 ±0.7%), and MISD >6 h (48.1 ±1.1%). Irregular milking is also known
to impair udder health and increase the SCC of cows.
Conclusions
Milking interval between 4 to 8 hours minimizes DSCC, which aims the natural MI of suckling calves. A more
regular milking interval in AMS farms could reduce DSCC and therefore improve udder health. AMS farms
should strive their management and settings of the AMS to encourage cows to visit the AMS more regularly.
Acknowledgement
We kindly acknowledge the QNETICS GmbH, Erfurt, Germany, for providing the dataset of DSCC values and
milk yield recording data for this study.


Prevalence of tail injuries in German Dairy cows

Kremer-Rücker, P.; Meier, S. (2022)

Proceedings of the 31. World Buiatric Congress, September 4th-8th, Madrid, 2022, AH-34 (1), S. 111-112.

 

Objectives
Tail injuries and pathological alterations have been reported in many species. In cattle, they were investigated
mainly in fattening bulls and feedlot cattle. In dairy cows high prevalences for different tail alterations were
found. However, aetiology and pathogenesis of this health trait are still unclear and need further investigation.
Out of 4443 phenotypes of different tail alterations we assorted seven groups common in dairy cows: 1. very
tip of the tail , 2. ring-like, 3. scurf, 4. swelling, 5. thinning, 6. axis anomaly, and 7. verruca-like mass. The
objective of this study was to identify genomic regions that may influence the occurrence of different tail
alterations in dairy cows, which could be useful for a potential implementation of a genomic selection tool for
more robust and healthy cows in the future.
Material and methods
Data collection started in December 2019 from a German 75 German Holstein (HOL) cows dairy herd. All cows were
examined every two weeks during six months regarding any kind of tail alterations. The findings were described and
photographed. Data analysis resulted in seven different kinds of tail alterations: 1. very tip of the tail, 2. ring-like, 3. scurf,
4. swelling, 5. thinning, 6. axis anomalies, and 7. verruca-like mass.
Hereinafter, prevalences for the observed tail alterations were calculated based on monthly data collection from five
different dairy herds: 3 HOL herds, counting average herd sizes of 75, 300, and 1300, respectively; 2 German Fleckvieh
(FV) herds, counting 60 cows, each. All cows were housed in free stall barns with conventional (HOL, FV) or automatic
milking systems (FV).
In total, 4443 Dairy Cows' Tail Scores were recorded. Data preparation and analysis were performed using R version
4.1.2. Prevalences for tail alterations were calculated by dividing the number of observations within by the total number of
observations of each kind of tail alteration and was given in percent. For calculating the total prevalence per breed and
farm, the occurrence of at least one tail alteration counted as an observation, was divided by the total number of cows
under investigation and given in percent.
Results
The overall prevalence for any kind of tail alteration was 88% in German Holstein and 99% in Fleckvieh cows; it varied
between farms from 74% to 99%. Prevalences for HOL and FV regarding alterations of the very tip of the tail were 26%
and 71%, ring-like alterations 24% and 30%, swelling 26% and 42%, scurf 55% and 60%, thinning combined with axis
anomalies 16% and 21%, and verruca-like mass 10% and 21%, respectively. Number per tail ranged for ring-like
alterations and thinning/axis anomalies from 1 to 5 and for verruca-like mass from 1 to 3.
Conclusions
During this study, high prevalences for different tail alterations in HOL and FV dairy cows were found out. The grouping of
different alterations as described above can be useful to phenotype tail alterations in dairy cows. However, further
investigations regarding pathogenesis, aetiology, and genetics of the observed alterations in dairy cows' tails are needed
to understand their origin and impact on animal health and welfare.
Funding
This research was funded by the Tönnies Forschung, Rheda, Germany.

more

Genome-wide association study for tail alterations in German Holstein dairy cows

Kremer-Rücker, P.; Schubert, K.; Meier, S. (2022)

Proceedings of the 31. World Buiatric Congress, September 4th-8th, Madrid, 2022, GB-P02 (2), S. 89-90.

 

Objectives
Tail injuries and pathological alterations have been reported in many species. In cattle, they were investigated
mainly in fattening bulls and feedlot cattle. In dairy cows high prevalences for different tail alterations were
found. However, aetiology and pathogenesis of this health trait are still unclear and need further investigation.
Out of 4443 phenotypes of different tail alterations we assorted seven groups common in dairy cows: 1. very
tip of the tail , 2. ring-like, 3. scurf, 4. swelling, 5. thinning, 6. axis anomaly, and 7. verruca-like mass. The
objective of this study was to identify genomic regions that may influence the occurrence of different tail
alterations in dairy cows, which could be useful for a potential implementation of a genomic selection tool for
more robust and healthy cows in the future.
Material and methods
Occurrence data of each tail alteration group were collected monthly from 167 German Holstein cows. The
cows originated from a German 1300 cows dairy herd. Data collection was performed from May to December
2021, since calving of all included cows was from April to May. The cows were in their first to seventh lactation.
The phenotype was encoded binary, where 0 means the absence and 1 the presence of a tail alteration group
within the whole timespan.
For 118 cows, Illumina EuroG10k genotypes were available and imputed up to 45k (FImpute). The remaining
cows were genotyped with the Illumina EuroG MD (V1, V1.1, V2) with 45613 SNPs. After quality check (only
segregating SNPs, at least two groups with a minimum of 10 observations, no duplicated markers, a minor
allele frequency of 1%, and within Hardy-Weinberg-Equilibrium P>0.01), 41062 SNPs remained.
A genome-wide association study was performed using the software GEMMA and the univariate linear mixed
model. Each tail alteration group was treated as a separate phenotype. A standardized relatedness matrix was
included in the model and calculated on SNP chip data to consider the population stratification, since many
half-sib groups were present. The lactation (1st, 2nd, ≥3rd) was included as covariate. The genotype matrix was
included in the model and the effect size per marker was estimated and tested for significance using a Wald
test.
For positional candidate gene analysis, genomic regions around top markers (P < 0.0001) of 325kbp wereconsidered,since the linkage disequilibrium decay analysis gave a mean r² of >0.61 within this distance. The
marker positions are given on the ARS-UCD 1.2 Bos taurus genome assembly.
Results
In total 51 top markers resulted for all seven tail alteration groups, whereof one marker reached Bonferronicorrected
genome-wide significance threshold for tail alteration group “thinning” (BTA1: rs42577957, −log10(P)
= 9.22). The markers were found on 18 different chromosomes. Close to these markers, 65 positional
candidate genes reside. Among them CCDC122 (rs42421906, −log10(P) = 5.46), which was associated with
the phenotype “scurf” in our analysis. CCDC122 is one of the top differentially expressed genes in liver
metabolism in pigs showing swine inflammation and necrosis syndrome (Ringseis et al., 2021). This syndrome
results in severe tail alterations in pigs as well.
Conclusions
This first genetic investigation of tail alterations in dairy cows showed the potential of finding genetic markers
for this novel health trait. Nonetheless, it is recommended to increase the sample size of cows and to further
investigate the cause of tail alterations, to substantiate the reported phenotypes.

Literature

Ringseis, R., Gessner, D. K., Loewenstein, F., Kuehling, J., Becker, S., Willems, H., et al. (2021). Swine inflammation and necrosis syndrome is associated with plasma metabolites and liver transcriptome in affected piglets. Animals 11, 1–14. doi:10.3390/ani11030772

Sargolzaei, M., Chesnais, J. P., and Schenkel, F. S. (2014). A new approach for efficient genotype imputation using information from relatives. BMC Genomics 15. doi:10.1186/1471-2164-15-478

Zhou, X., and Stephens, M. (2014). Efficient Algorithms for Multivariate Linear Mixed Models in Genome-wide Association Studies. Nat Methods 11, 407–409. doi:10.1038/nmeth.2848

Acknowledgement
We thank the MASTERRIND GmbH, Verden, Germany, for providing the genotypes from the investigated
cows.
Funding
Part of the data results from the project TINCa Dairy, which is funded by the Tönnies Forschung, Rheda,
Germany.

more

Using Thermal Imaging to Detect Tail Tip Alterations in Dairy Cows

Meier, S.; Abel, K.; Kremer-Rücker, P. (2021)

72nd Annual Meeting of the European Federation of Animal Science, 30. August - 03. September, Davos 2021 (27), S. 157.
DOI: 10.3920/978-90-8686-918-3

 

In fattening bulls tail tip alterations are described as health issues associated with (sub)acute rumen acidosis and lameness. Investigations of dairy cows’ tail tips are scarce; however, there is evidence that tail tip alterations occur as a result of intensive feeding management and metabolic imbalance. In June 2020, we investigated 68 German Holstein cows for tail tip alterations using a handheld thermal camera (FLIR® T1030). Thermal images of the shaved tail tip were taken from two different perspectives: (p1) tail in front of the udder and (p2) held tail in front of the ground. Additionally, all cows were evaluated for any kind of tail tip alterations, body condition score (BCS), and locomotion score (LMS). Milk yield data, resulting from latest performance testing were collected, too. Images were analysed using FLIR Tool+ and a generalised linear model was used to correct measured temperatures for fixed effects. The prevalence of tail tip alterations, regardless the findings, was 94%. Raw temperature data showed high correlations of r² = 0.79 for maximum and average temperature and r² = 0.70 for minimum temperature between p1 and p2 (P < 0.001). Tail tip necroses and BCS > 3 decreased the tail’s temperature, while swelling of the tail tip increased its temperature. Average, maximum and minimum temperatures for perspective 1 and 2 were 34.05 (±0.16) and 33.78 (±0.20) °C, 35.46 (±0.11) and 35.52 (±0.11) °C, and 30.30 (±0.30) and 29.22 (±0.38) °C, respectively. Temperatures of necrotic tissues (n = 4) decreased on average by 8.38 °C compared to the average temperature and were close to the minimum. We concluded thermal imaging can be used for the detection of alterations regarding the tail’s temperature, which could allow an early-warning system for swellings, probably caused by inflammation and possibly resulting in necroses. Further studies are needed to evaluate the praevalence of tail tip alterations in dairy cows on larger samples and to clarify their etiology. However, thermal imaging can be used as an early-warning system for tail alterations. Each early-warning system regarding health issues, improves animal welfare as it allows adapting management strategies early.

more

Development of a Tail Scoring as Health Indicator for Dairy Cows

Meier, S.; Abel, K.; Kremer-Rücker, P. (2021)

Proceedings of the 44th ICAR Annual Conference virtually held from Leeuwarden, NL 2021 (25), S. 1-6.

 

Research investigating necrotic tail tips in dairy cows resulting in necrotic tissues is scarce. However, there is evidence that in dairy cattle tail tip necroses exist with high prevalence. In piglets, the latest research described tail and ear necroses not because of tail and ear biting only, but because of swine inflammation and necrosis syndrome (SINS). Besides tails and ears, SINS includes inflammation of claws, heels, and teats. In cattle, tail tip necroses are described mainly in fattening bulls. As known so far, these findings are often discussed related to slatted flooring, intensive housing systems and management strategies. However, an association with subacute rumen acidosis and laminitis is described.

In order to investigate what kind of and how often tail tip alterations appear in dairy cattle, data of 87 German Holstein dairy cows were collected over a period of 12 months. All cows were evaluated for tail tip alterations, body condition score (BCS), and locomotion score (LMS) every two weeks. In addition, milk yield data resulting from performance testing were included. Thermographic images of the tails were taken once. Firstly, all kind of tail tip alterations were described and collected. After 6 months, we categorized the observed alterations and developed a tail scoring system. The scoring for each specified trait (tail tip, tail ring) ranged from 0 to 4.

The overall prevalence for tail alterations was 94%. Especially tail tip alterations had a constantly high prevalence of 56%. Cows affected by an increased average tail tip score, showed higher locomotion scores compared to others (P = 0.02). The prevalence of ring-like tail alterations increased from first to second lactation cows from 9 to 46%. Regarding the BCS, lighter cows showed higher scores due to ring-like alterations than heavier cows (P = 0.054). The most often occurring anomalies of the tail were sports or scurf (21.6%), followed by verruca-like mass (10.2%), swelling (8.4%), and thinning (4.3%).

The results and especially the scoring system can serve as a template for further studies considering larger samples sizes, to investigate prevalence for tail necroses and other tail anomalies in different herds and management systems. It was hypothesized, that an inflammatory condition in dairy cows showing up in altered/necrotic tail tips or rings exists, which is in relationship with claw disorders indicated by lameness. If so, the tail score of a cow could be used as health indicator to evaluate the health status in dairy production systems.

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Prediction of body composition in mirror carp (Cyprinus carpio) by using linear measurements in vivo and computed tomography post-mortem

Maas, P.; Grzegrzółka, B.; Kreß, P.; Oberle, M.; Judas, M.; Kremer-Rücker, P. (2020)

Archives Animal Breeding 63 (1), S. 69-80.
DOI: 10.5194/aab-63-69-2020


Open Access
more

In vivo – determination of the fat content in mirror carps (Cyprinus carpio) using ultrasound, microwave and linear measurements

Maas, P.; Grzegrzółka, B.; Kreß, P.; Oberle, M.; Kremer-Rücker, P. (2019)

Aquaculture 512, 734359.
DOI: 10.1016/j.aquaculture.2019.734359

 

Carps are the third largest species in aquaculture worldwide and belong to the fish family ‘cyprinids’, which make up the largest part of aquaculture production. The production of lean carp is one of the main goals in the carp farming business. Carps are usually traded alive; in order to ensure product quality and achieve a high consumer acceptance, it is important to estimate the fat content of the living fish. Therefore, during this study, a total of 250 living carps were examined using a mobile ultrasound device. Additionally, a microwave technology based Fish Fatmeter (Distell, Fauldhouse, Scotland, UK) was used to determine the fat content of the living fish. Further measurements included weight, lengths, height and circumferences. The ultrasound measurements were performed on non-sedated fish using narrow water-filled containers. Two sagittal images per fish were taken to measure the backfat thickness at defined locations. Subsequently, the fish were taken out of the water in order to determine the fat content using the Fish Fatmeter. Weight and linear measurements were taken. After the in vivo measurements, about 10 fish per pond, in total 51 fish, were slaughtered and the fillets were analysed chemically. Linear regression models were developed. The Fish Fatmeter turned out to be an accurate method to determine the fat content of the fillet in mirror carps (R2 = 0.95). Regarding the ultrasound measurement of the backfat thickness, moderate correlations between ultrasound and Fish Fatmeter were achieved (R2 = 0.33–0.45). Pearson's correlation for linear measurement and the Fish Fatmeter showed negative prediction. In order to evaluate the relative backfat thickness, the ultrasound measurement was divided by linear measurements. The best correlation was found using the ultrasound measurement point where the backfat thickness reached a constant thickness divided by the circumference around the thinnest part of the tail fin (R2 = 0.74). In the next step, the carps were divided into groups of ten fish per pond. The mean Fish Fatmeter measurement and ultrasound measurement divided by circumference was calculated and correlated achieving an R2 of 0.92. Based on these findings, it seems plausible to estimate the fat content using a small sample of ten fish with an ultrasound device and a measuring tape.

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Size matters: Boar taint in relationship with body composition and testis volume measured by magnetic resonance imaging

Bernau, M.; Schwanitz, S.; Kremer-Rücker, P.; Kreuzer, L.; Scholz, A. (2018)

Livestock Science 213, S. 7-13.
DOI: 10.1016/j.livsci.2018.04.008


Open Access
more

Body composition and boar taint of intact boars, and immunologically or surgically castrated pigs

Schwanitz, S.; Bernau, M.; Kreuzer, L.; Kremer-Rücker, P.; Scholz, A. (2017)

Züchtungskunde 89 (6), S. 413-433.

more

Magnetic resonance imaging to detect local tissue reactions after vaccination in sheep in vivo

Bernau, M.; Kremer-Rücker, P.; Kreuzer, L.; Schwanitz, S.; Cussler, K.; Hoffmann, A....

Veterinary Record Open 4, e000200 (1), S. 1-7.
DOI: 10.1136/vetreco-2016-000200


Open Access
more

Genome-wide QTL mapping results for regional DXA body composition and bone mineral density traits in pigs

Rothammer, S.; Bernau, M.; Kremer-Rücker, P.; Medugorac, I.; Scholz, A. (2017)

Archives Animal Breeding 60 (2), S. 51-59.
DOI: 10.5194/aab-60-51-2017


Open Access
more

Are testis volume and boar taint related? - a trial in entire and immunocastrated boars

Bernau, M.; Schwanitz, S.; Kreuzer, L.; Kremer-Rücker, P.; Scholz, A. (2016)

Book of Abstracts (Vol. 22) of the 67th Annual Meeting of the European Federation of Animal Science, 29. August - 2. September 2016 in Belfast (UK).


Are testis volume and boar taint related? – a trial in entire and immunocastrated boars

Bernau, M.; Schwanitz, S.; Kreuzer, L.; Kremer-Rücker, P.; Scholz, A. (2016)

67th Annual Meeting of the European Federation of Animal Science, 29. August – 2. September 2016 in Belfast, UK.


Local reactions after vaccination detected via magnetic resonance imaging and compared with pathomorphological examination

Bernau, M.; Kremer-Rücker, P.; Kreuzer, L.; Emrich, D.; Pappenberger, E.; Cussler, K....

Proceedings of the 24th International Pig Veterinary Society Congress, 7-10. Juni 2016 in Dublin (Irland).


Local reactions after vaccination detected via magnetic resonance imaging and compared with pathomorphological examination

Bernau, M.; Kremer-Rücker, P.; Kreuzer, L.; Emrich, D.; Pappenberger, E.; Cussler, K....

24th International Pig Veterinary Society Congress, 7.-10. Juni 2016 in Dublin, Irland.


Assessment of local reaction to vaccines in live piglets with magnetic resonance imaging compared to histopathology

Bernau, M.; Kremer-Rücker, P.; Kreuzer, L.; Emrich, D.; Pappenberger, E.; Cussler, K....

Alternatives To Animal Experimentation (ALTEX) 33 (1), S. 29-36.
DOI: 10.14573/altex.1507211


Open Access
more

Prof. Dr. med. vet. habil. Prisca Kremer-Rücker


Hochschule Weihenstephan-Triesdorf

Fakultät Landwirtschaft, Lebensmittel und Ernährung
Fakultät Landwirtschaft, Lebensmittel und Ernährung Markgrafenstraße 16
91746 Weidenbach

T +49 9826 654-203
prisca.kremer-ruecker[at]hswt.de