Association of Some Hematological Parameters, Blood Glucose, Thyroid Hormones and Repeat Breeding Syndrome: A Case-Control Study

Background and Objective: A repeat breeder (RB) cow is not conceived after three consecutive inseminations.This study examined the association of Haemoglobin (Hb), packed cell volume (PCV), total erythrocytes count (TEC), total leukocytes count (TLC), plasma glucose and thyroid hormones (T3 and T4) with repeat breeding syndrome in cross-bred dairy cows reared under the semi-intensive system.Materials and Methods: Twenty crossbred multiparous, apparently healthy dairy cows with the age of 4-8 years and a body condition score of 2.5-3 were used.The animals were divided into two equal groups.Group A (n = 20) were healthy normal cyclic cows used as control.Group B (n = 20) were RB cows.Blood samples were collected once from all animals for measuring the Hb, PCV, TEC, TLC, glucose, T3 and T4.Results: When compared to the normal cyclic cows, no significant differences were detected (p>0.05) in the Hb, PCV, TEC, serum T3 and T4 in RB cows, but the TLC was significantly higher (8.2±0.5 vs 5.5±0.12103 mLG 1 , p<0.05) and the blood glucose level were significantly lower in the RB (44.9±5.0 vs. 54.6±6.5 mg dLG 1 , p<0.05).Conclusion: The hypoglycemia and leukocytosis were associated with repeat breeding syndrome in cross-dairy cows under the study.