Publikationsdatenbank

Efficacy of a treatment with hCG 4 days after AI to reduce pregnancy losses in dairy cows after synchronized ovulation - Preliminary results (2007)

Art

Vortrag

Autoren

Fischer-Tenhagen, C.

Thiele, G.

Heuwieser, W.

Tenhagen, B. A.

Kongress

40th Annual Conference of Physiology and Pathology of Reproduction and 32nd Mutual Conference on Veterinary and Human Reproductive Medicine

Berlin, 22. – 23.02.2007

Quelle

Reproduction in Domestic Animals, 42, Suppl. 1 (2007), 6

Verweise

URL (Volltext): http://www.blackwell-synergy.com/toc/rda/42/s1

Kontakt

Tierklinik für Fortpflanzung

Königsweg 65
Haus 27
14163 Berlin
+49 30 838 62618
fortpflanzungsklinik@vetmed.fu-berlin.de

Abstract / Zusammenfassung

The objective of the study was to investigate, whether a
treatment with hCG 4 days after AI could reduce pregnancy
losses in high yielding dairy cows. Non pregnant cows of
one commercial dairy herd were examined weekly in the
course of a reproductive management protocol. Cows with
no corpus luteum (CL) were treated with an Ovsynch
protocol [0.01mg of buserelin (Receptal®, Intervet
Deutschland GmbH, Unterschleissheim) on days 0 and 9,
0.15 mg of cloprostenol (Cyclix®, Intervet Deutschland
GmbH, Unterschleissheim) on day 7, AI 16 to 20 hrs after
the second buserelin treatment, Group OV)]. Cows with a
CL received cloprostenol (0.15 mg) on day 0, buserelin
(0.01mg) on day 2 and AI 16 to 20 hrs later (Group PG).
Cows in both treatment protocols were then assigned to two
groups by their identification number (even vs. odd
numbers) to receive or not to receive 2,500 IU of hCG i.v.
four days after AI (Ovogest®, Intervet Deutschland GmbH,
Groups OV-hCG, OV-Cont, PG-hCG and PG-Cont).
Pregnancy diagnosis was carried out via ultrasound on day
27 after AI (n=525) and on day 39 (n=491) by rectal
palpation. Pregnancy losses were defined as cows being
pregnant on day 27 but not pregnant on day 39. Pregnancy
rate (PR) by day 27 did not differ between the four
treatment groups (27.1, 33.8, 28.9, 29.3 % for Groups OVhCG,
OV-Cont, PG-hCG and PG-Cont). Pregnancy losses
between day 27 and day 39 were lower in hCG treated
animals (23 vs. 40 %, P=0.043). PR on day 39 did not differ
significantly between groups (21.2, 19.7, 27.2, and 20.7 %
for Groups OV-hCG, OV-Cont, PG-hCG and PG-Cont). In
conclusion, treatment with hCG 4 days after AI did not
significantly increase PR on days 27 and 39 after
synchronized ovulation and timed AI but reduced pregnancy
loss during this period. The authors acknowledge the
support of Intervet Deutschland GmbH.