نتایج جستجو برای: lactation cycle
تعداد نتایج: 288077 فیلتر نتایج به سال:
Glutamine is the most abundant free alpha-AA in the mammalian body, and large amounts of glutamine are extracted by both the fetus during pregnancy and the mammary gland during lactation. The work presented here addressed the hypothesis that there would be major changes in glutamine metabolism in the mare during the transition period, the time between late gestation, parturition, and early lact...
The objective was to utilize data from modern US dairy cattle to determine the effect of days dry on fat and protein yield, fat and protein percentages, days open, and somatic cell score in the subsequent lactation. Field data collected through the dairy herd improvement association from January 1997 to December 2003 and extracted from the Animal Improvement Programs Laboratory national databas...
Test-day milk yield and somatic cell count data over extended lactation (lactation to 540-600 days) were analysed considering part lactations as different traits and fitting random regression (RR) models. Data on Australian Jersey and Holstein Friesian (HF) were used to demonstrate the shape of the lactation curve and data on HF were used for genetic study. Test-day data from about 100 000 cows...
We evaluated the effect of a high-protein diet (HP) on pregnancy, lactational and rearing success in mice. At the time of mating, females were randomly assigned to isoenergetic diets with HP (40% w/w) or control protein levels (C; 20%). After parturition, half of the dams were fed the other diet throughout lactation resulting in four dietary groups: CC (C diet during gestation and lactation), C...
Lactation is associated with significant alterations in both body composition and bone mass. Systemic and local skeletal factors such as receptor activator of nuclear factor κ-B ligand (RANKL), PTHrP, calcitonin, and estrogen are known to regulate bone remodeling during and after lactation. Fibroblast growth factor 21 (FGF-21) may function as an endocrine factor to regulate body composition cha...
Nutrition has a significant effect on reproduction and lactation in Ruminant. Supply of require nutrient of dairy cows and ewes in early lactation is the main challenges that will be considered, since in most cases the animals facing negative energy balance after calving and the beginning of the period of lactation. Negative energy balance may sometimes result in reduced livestock production an...
Mammals are characterised by their ability to provision offspring with milk, but lactation is normally restricted to females. Why do most males not share this trait? The morphological and physiological modifications necessary for male lactation are possible and, although restrictive, the ecological factors that could select for male lactation seem common enough. Until quite recently, there was ...
Because pregnancy and estrogens both induce pituitary lactotroph hyperplasia, we assessed the expression of pituitary cell cycle regulators in two models of murine pituitary hyperplasia. Female mice were assessed during nonpregnancy, pregnancy, day of delivery, and postpartum. We also implanted estradiol (E(2)) pellets in female mice and studied them for 2.5 months. Pituitary weight in female m...
in this study a total of 171,360 monthly test day milk records obtained from first lactation of iranian holstein cattle (three times a day milking) distributed in 96 herds and calved from 1999 to 2008 were used to estimate genetic parameters and to predict breeding values of the animals. the data was analyzed using random regression test day model. the results showed that average of heritabilit...
in this paper, the effects of input temperature and compression ratio on the net output work and efficiency of the air standard cycles, i.e. atkinson cycle, diesel cycle and otto cycle are analyzed. we assumed that the compression and power processes are adiabatic and reversible and any convective, conductive and radiative heat transfer to cylinder wall during the heat rejection process may be ...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید