Untersuchungen über die Bestimmung der Spermaqualität - insbesondere Motilität und Membranintegrität - und Zusammenhänge zur Fertilität von Besamungshengsten

Es wurden insgesamt 181 Besamungsdosen von 34 in der Besamung eingesetzten Hengsten untersucht. Die Motilität wurde von bis zu 7 Personen geschätzt und mit 2 computerassistierten Programmen ausgewertet. Die Membranintegrität wurde anhand der Bromphenolblau-Nigrosin und der neuen Kovács-Foote Färbung ausgewertet (letztere beurteilt auch die Integrität der Akrosom- und Mittelstückmembran). Die so gewonnenen Daten wurden mit der erzielten Trächtigkeiten der Stuten verglichen

Zuchtprogramme ohne Biotechnologie - Etablierung von Bockringen in der Ziegenzüchtung

Within organic livestock farming, the use of AI versus natural mating is under steady discussion. However, no special organic breeding programs without AI are set in place so far. The present study takes goat breeding in Germany as an example to show how an organic breeding program without biotechnology could be organised. As basis, breeding planning on different breeding plans is carried out: the breeding program in place, a breeding program with buck rotation within “buck circles” and a breeding program with AI are evaluated. It can be shown that within smaller populations (here: goat breeding in South Germany) a buck rotation scheme with progeny testing is superior in genetic gain than the actual and a breeding program based on AI. In a second step, in discussions with different stakeholders and farmers the hygiene plan of the buck circle was discovered as the critical point. A detailed hygiene plan has to be worked out and agreed upon by all participants. Still, the participating farmers have to trust all members of the group, because the compliance with the regulations is only limited controllable

Isolation and Cultivation of a New Isolate of BTV-25 and Presumptive Evidence for a Potential Persistent Infection in Healthy Goats

Recently, several so-called “atypical” Bluetongue virus (BTV) serotypes were discovered, including BTV-25 (Toggenburg virus), in Switzerland. Most “atypical” BTV were identified in small ruminants without clinical signs. In 2018, two goats from a holding in Germany tested positive for BTV-25 genome by RT-qPCR prior to export. After experimental inoculation of the two goats with the BTV-25 positive field blood samples for generation of reference materials, viremia could be observed in one animal. For the first time, the BTV-25-related virus was isolated in cell culture from EDTA-blood and the full genome of isolate “BTV-25-GER2018” could be generated. BTV-25-GER2018 was only incompletely neutralized by ELISA-positive sera. We could monitor the BTV-25 occurrence in the respective affected goat flock of approximately 120 goats over several years. EDTA blood samples were screened with RT-qPCR using a newly developed BTV-25 specific assay. For serological surveillance, serum samples were screened using a commercial cELISA. BTV-25-GER2018 was detected over 4.5 years in the goat flock with intermittent PCR-positivity in some animals, and with or without concomitantly detected antibodies since 2015. We could demonstrate the viral persistence of BTV-25-GER2018 in goats for up to 4.5 years, and the first BTV-25 isolate is now available for further characterization