this study was conducted to evaluate the effects of alfalfa hay (ah) particle size and soybean hull (sh) on physical effective fibre (pendf), particle size distribution in diets, chewing activity as well as milk composition and production in early lactating dairy cows. eight lactating holstein cows averaging 590±33 kg of bw and 47±13 days in milk were assigned in a 4×4 latin square design to a ...

the aim of this study was to determine the factors affecting stillbirth and the consequences of stillbirth on longevity, production, and reproductive performance in holstein cows of iran. calving records from march 2000 to april 2009 comprising of 220,043 calvings on 102,199 cows in 33 herds were used. the results showed that 4.06% of the newborn calves died within 48 h of birth. the stillbirth...

milk samples from high and low milk producer holstein cows, were obtained during the morning and afternoon milking over a one week period. overall, 1064 samples were tested within 14 times sampling in urmia, iran. milk macro-mineral concentrations in the morning milking and in low producers were greater than in the afternoon and in high producers. the highest and lowest concentrations were obse...

This field study aimed to investigate the relationships between the urinary zearalenone (ZEN) concentration, which reflects dietary ZEN intake, and the numbers of total and transferable embryos in superovulated cattle. A total of 38 cows (Japanese Black, n=16; Holstein, n=22) were superovulated for commercial embryo production. Urine samples were collected from all cows at the time of embryo fl...

The number of dermal mast cells in several European and Zebu cattle breeds was determined and correlated with the tick load. Breeds included European registered and non-registered Holstein, Brown-Swiss and Jersey cows, Zebu (Nelore and Gyr) and crossbred cows with either high or low tick infestations. Animals were naturally infested with Rhipicephalus (Boophilus) microplus and evaluated at regu...

The traits particularly important for milk production include milk yield, protein percentage, fat percentage, and the somatic cell score. Alpha-lactalbumin (α-LA) is an important whey protein of cow milk, and is also present in the milk of many other mammalian species. In this study, we analyzed the genetic polymorphisms of the α-LA gene and their relationship to milk production traits (milk yi...

This study was conducted to investigate the effect of the interval between the onset of spontaneous estrus and artificial insemination (AI) on reproductive performance and calf sex ratio in repeat breeder Holstein cows. Two hundred eighty lactating Holstein cows were used in this study. The animals were artificially inseminated at different times (0–6, 7–12, 13–18, or 19–24 h) after the onset o...

The objective of this study was to determine the effect of different levels of sesame wastes (SW) on performance, milk composition and blood metabolites in lactating dairy cows. In this order, eight multiparous Holstein dairy cows were used in a replicated 4×4 Latin square design in four periods of 21 days. Treatments were control (no Sesame meal supplementat...

The objective of this study was to determine the effect of different levels of sesame wastes (SW) on performance, milk composition and blood metabolites in lactating dairy cows. In this order, eight multiparous Holstein dairy cows were used in a replicated 4×4 Latin square design in four periods of 21 days. Treatments were control (no Sesame meal supplementat...

The aim of this paper was to determine effects of selected genetic and environmental factors on the concentration of acetone in blood of cows in the first trimester of lactation. The study included 124 Polish Holstein-Friesian primiparous cows born, reared and managed on the same farm. The samples of blood were collected on day 2, 5, 30, 60 and 90 after calving. The highest serum acetone concen...