Milk progesterone level is a good marker to evaluate the functional status of the corpus luteum in all farm animals. The present study was conducted to monitor changes in milk progesterone concentrations at the time of oestrus and post-mating for diagnosing early pregnancy in Anatolian water buffaloes. Twenty-one buffaloes reared at the Kocatepe Agricultural Research Institute, Afyon, Turkey, were used. Milk samples were collected on Days 0 (D0: oestrus-mating), 11, 19, 21 and 24, and then every 3-4 days until Day 45. They were stored at 4 °C and analysed by the enzyme immunoassay (EIA) method. Rectal palpation was performed on Day 60 to confirm pregnancy. Although 16 animals had elevated levels of progesterone on Day 19 and Day 24, pregnancy was only confirmed in 12 of them on Day 60. Although the other 4 buffaloes had elevated levels of progesterone and did not return to oestrus during Day 19 and Day 24, they were confirmed non-pregnant on Day 60. Two of these non-pregnant buffaloes with elevated progesterone levels had increased progesterone levels even on Day 45 and did not return to oestrus. In the remaining 2 non-pregnant buffaloes with elevated progesterone levels, progesterone concentrations declined gradually (1.2 ng/ml on Day 31 and 0.88 ng/ml on Day 45). The other 5 buffaloes were diagnosed non-pregnant based upon the milk progesterone assay. Mean progesterone concentration in these non-pregnant buffaloes was 0.88 ± 0.37 ng/ml between Days 19 and 24. The accuracy rate, sensitivity, specificity and the detection rate of pregnancy and non-pregnancy of progesterone assay were 81.0, 100.0, 56.0, 75.0 and 100.0%, respectively. In conclusion, milk progesterone assay is a fast and reliable tool to detect oestrus time and non-pregnant buffaloes with a 100.0% accuracy rate. In addition, this assay may also give an idea about early pregnancy during Days 19-24 of gestation and may be used to predict some reproductive disorders which cause infertility and economic losses in Anatolian buffaloes.

Milk progesterone level is a good marker to evaluate the functional status of the corpus luteum in all farm animals. The present study was conducted to monitor changes in milk progesterone concentrations at the time of oestrus and post-mating for diagnosing early pregnancy in Anatolian water buffaloes. Twenty-one buffaloes reared at the Kocatepe Agricultural Research Institute, Afyon, Turkey, were used. Milk samples were collected on Days 0 (D0: oestrus-mating), 11, 19, 21 and 24, and then every 3-4 days until Day 45. They were stored at 4 °C and analysed by the enzyme immunoassay (EIA) method. Rectal palpation was performed on Day 60 to confirm pregnancy. Although 16 animals had elevated levels of progesterone on Day 19 and Day 24, pregnancy was only confirmed in 12 of them on Day 60. Although the other 4 buffaloes had elevated levels of progesterone and did not return to oestrus during Day 19 and Day 24, they were confirmed non-pregnant on Day 60. Two of these non-pregnant buffaloes with elevated progesterone levels had increased progesterone levels even on Day 45 and did not return to oestrus. In the remaining 2 non-pregnant buffaloes with elevated progesterone levels, progesterone concentrations declined gradually (1.2 ng/ml on Day 31 and 0.88 ng/ml on Day 45). The other 5 buffaloes were diagnosed non-pregnant based upon the milk progesterone assay. Mean progesterone concentration in these non-pregnant buffaloes was 0.88 ± 0.37 ng/ml between Days 19 and 24. The accuracy rate, sensitivity, specificity and the detection rate of pregnancy and non-pregnancy of progesterone assay were 81.0, 100.0, 56.0, 75.0 and 100.0%, respectively. In conclusion, milk progesterone assay is a fast and reliable tool to detect oestrus time and non-pregnant buffaloes with a 100.0% accuracy rate. In addition, this assay may also give an idea about early pregnancy during Days 19-24 of gestation and may be used to predict some reproductive disorders which cause infertility and economic losses in Anatolian buffaloes.