Milk progesterone determination in buffaloes post-insemination.
Milk progesterone levels were studied in 17 buffaloes between post-insemination and 30 days thereafter. Six animals were confirmed pregnant. Seven of 10 animals took greater than 24 days to return to oestrus and the pattern of change of progesterone levels indicated a steady increase from 1 ng/ml on day 2 to 20 ng/ml on day 14 post-insemination, falling subsequently to about 5 ng/ml, 2 days prior to oestrus. In pregnant buffaloes, the milk progesterone levels showed a continuous increase up to 20 days post-insemination but did not decline thereafter. In individual buffaloes returning to oestrus, a cut-off milk progesterone level of greater than 10 ng/ml was considered for pregnancy diagnosis, 20, 22 and 24 days post-insemination. The test was 60, 75 and 75% accurate for detection of pregnancy on days 20, 22 and 24 respectively and 100% for non-pregnancy diagnosis on all three days. Individual animals showed a highly variable oestrous cycle length, which has been suggested as a contributory factor for false pregnancy diagnosis by milk progesterone test in this species. Milk progesterone assay may also identify silent heats, and clinical disorders.
Gupta
M
M
Division of Cattle Physiology, National Dairy Research Institute, Karnal, India.
Prakash
B S
BS
D000818:Animals; D002020:Buffaloes / Q000378:metabolism*; D004971:Estrus / Q000378:metabolism*; D005260:Female; D008892:Milk / Q000737:chemistry*; D011258:Pregnancy Tests / Q000662:veterinary*; D011374:Progesterone / Q000032:analysis*
D011374:Progesterone