The dairy cows post-partum period dynamics during the ovaries ovulatory function recovery and depression

Abstract

A significant problem in the dairy farming industry is the decrease in the livestock reproductive capacity due to the ovaries physiological functions violation. This study examines the lipids, proteins and carbohydrates metabolism state, depending on the sexual cyclicity recovery in animals degree, while observing adequate feeding. For the experiment, 16 new-calving Holstein-Friesian cows with an average annual milk yield of 9.5 thousand kg were selected, divided into 2 equal groups, depending on the ovulatory function resumption. All animals received a balanced diet. Blood was taken on days 6, 12, 19, 40 and 68 after calving. Blood serum was separated and the total protein and individual fractions content, as well as the creatinine, urea, total lipids, cholesterol, triglycerides, glucose amount, were determined. To determine the hormonal status, the content of estradiol and progesterone was examined. The reproductive organs condition was assessed using transrectal palpation and using an ultrasound apparatus. We found that cows with ovarian dysfunction are characterized by protein and glucose globulin fraction decreased concentrations in the blood, increased creatinine content and hypothalamus-pituitary-gonad system hormone-producing function inhibition. With an accuracy of 87.5%, the glucose threshold level in the blood serum was revealed, at which ovarian dysfunction can be predicted: a decrease in fertility in cows is observed at a rate of <2.2 mmol/l. Taking into account the previous studies results, further research expediency on finding the hormonal and metabolic status relationship with ethology typological features and the central nervous system state is substantiated.

Influence of kappa-casein genotype on milk yield of cows and on culling of cows

“…A large array of Holsteinized black-and-white mottled cattle was derived in many regions of our country. Those breeds differ among themselves in economically useful traits and exterior features; the differences and features are related to the breeding zone and breed resources used in the crossing [7][8][9][10][11][12].…”