Pregnancy, decreased feed intake during late gestation, lactogenesis, and parturition have dramatic effects on metabolism in dairy cows during the transition period from 3 wk before calving to 3 wk after calving. Increases in plasma NEFA occur during the 10 d before calving and may precede the decrease in feed intake. Plasma NEFA concentrations are highest at calving and decrease rapidly after ...

other energy depots can be forced, however, genetic associations may remain when phenotypic regression is used. Heritability estimates for phenotypic residual feed intake have been moderate, ranging from 0.26 to 0.43. Genetic correlations of phenotypic residual feed intake with feed intake have been highly positive, suggesting that improvement would produce the correlated response of decreasing...

The present study conducted to investigate the effect of energy sources and levels on performance and breast meat amino acids profile in Cobb 500 broiler chicks. A total of 600 1-day-old Cobb 500 broiler chicks with an average weight of 39 ± 0.50 g were randomly divided into five treatments. Each treatment was further divided into four replicates. Chicks were fed a basal diet based on corn and ...

Fifty 18-day-old broilers were used to investigate the effects of 30% energy restriction from 18∼48 d on growth and slaughter performance, serum biochemical parameters, and gene expression of WDTC1 and Lpin2 in hepatic tissue. Fifty 18-day-old Arbor Acres female broilers were randomly divided to ad libitum group (control) and energy restriction group (experimental) and housed individually. The ...

T HE mechanisms regulating feed intake appear to be the same mechanisms that control energy exchange. The physiological functions brought into play are numerous and involve chemosensitive areas, reflex responses and integrative function of the central nervous system. Aside from the primary physiological factors limiting feed intake, a close relationship exists in ruminants between the content o...

The generation of co-products continues at an accelerating pace, driven by population growth. Many of these co-products can be included in ruminant feed, which has the ability to transform them into good quality animal protein, and also help to reduce the disposal of undesirable residues to the environment. One of the co-products with potential use in animal feed, the citrus pulp, represents re...

A review is presented of the genetic and physiological aspects of growth, body composition and feed efficiency in mice. The genetic parameters considered are: nature and extent of within and between-line genetic variation for body weight and growth rate; direct and correlated responses to selection for body weight, weight gain, feed intake and feed efficiency; direct genetic effects of the offs...

this experiment was conducted to determine the chemical composition and gross energy of poultry by product meal (pbpm) and the effects of different levels of inclusion of poultry by product meal on broiler chicken performance, serum uric acid and carcass characteristics. three samples of pbpm produced in ardabil province located in northwest of iran, were provided during one month sampling peri...