Evidence is presented that bovine somatotrophin (bST) treatment of lactating dairy cows enhances both expression of oviductal insulin-like growth factor II (IGF-II) mRNA and endometrial insulin-like growth factor binding protein 3 (IGFBP-3) mRNA between day 3 and day 7 of the oestrous cycle. mRNA encoding growth hormone (GH) receptor in endometrial tissues increased between day 3 and day 7 of t...

The concept of extended lactation should improve cow health and productivity while reducing greenhouse gas emissions per kg milk produced in high-yield organic dairy herds. This is achieved through fewer calvings per year and hence production of fewer replacement heifers. Combined with fewer days dry per cow per year, this will reduce the annual herd requirement for feed while maintaining milk ...

In pasture-based dairy systems, feeding a complex concentrate mix in the parlor during milking that contains cereal grains and protein supplements has been shown to have milk production advantages over straight grain. This experiment had aim of testing whether further could be elicited by adjusting composition an attempt match expected nutrient intake from pasture late spring. The used 96 lacta...

Increasing reproductive performance of post-partum lactating dairy cows is a multi-factorial challenge involving disciplines of production medicine, nutrition, physiology and herd management. Systems of programmed timed insemination have been fine-tuned to achieve pregnancy per artificial inseminations (AI) approximating 45%. Systems have optimized follicle development, integrated follicle deve...

The objectives were to evaluate pregnancy per AI (P/AI) of dairy cows subjected to the 5-day timed AI protocol under various synchronization and luteolytic treatments. Cows were either presynchronized or received supplemental progesterone during the synchronization protocol, and received a double luteolytic dose of PGF2α, either as one or two injections. In Experiment 1, dairy cows (n=737; Hols...

Background: Metabolic profiles have been used in efforts to predict pre parturient problems and fertility, to diagnose metabolic diseases, and to assess nutritional status in dairy cows. These profiles may help to confirm the diagnosis of sub clinical diseases, to be aware of possible causes of infertility in the herds, or to monitor improvement in herd animals. OBJECTIVES: This study investiga...

This study focuses on the effect of parenteral administration of Selenium (Se) and vitamin E on concentration of Se in plasma and the activity of glutathione peroxidase (GPx) in the blood of dairy cows during peripartal period and their effect on the reduction of clinical mastitis. From a 220 individuals Holstein herd in a two-four lactation-gestation cycle the control group (C), 1st (D1) and 2...

Twenty-four 3-year-old Angus cows (512.2±21.6 kg) and six ruminally cannulated beef heifers (523.1±16.9 kg) were used to determine the impact of feeding oilseeds starting at the beginning of estrous synchronization until maternal recognition of pregnancy on plasma fatty acid composition. Starting ~60 days postpartum cows were synchronized with the Select Synch+controlled internal drug-release (...

This work consists in studying the productive and reproductive performance of Holstein dairy cows (n=77) reared an intensive production system a Mediterranean climate, as well factors their variations. Meteorological data collected between 2017 2020 for region Beja, North-West Tunisia, revealed that average monthly values ​​of ambient temperature (Ta), relative humidity (HR) temperature-humidit...

2010 ii ABSRACT The objective of this study was to determine the success of a presynchronization program implemented on a modern dairy facility. The study was conducted on a 1,400 cow dairy in the central valley of California. 86 cows were involved in the study during the summer months of June through September. Cows were either assigned in the synchronization program or placed in a control gro...