Differential reproductive investment by the mother can critically influence offspring development and phenotype, and strong selection is therefore expected to act on such maternal effects. Although a genetic basis is a prerequisite for phenotypic traits to respond to selection and thus to evolve, we still know very little about the extent of heritable variation in maternal effects in natural po...

In this study, we produced a polyclonal antibody against unprocessed chicken myostatin and examined the effect of in ovo administration of the antibody on posthatch chicken growth and muscle mass. A PCR-amplified unprocessed chicken myostatin cDNA was cloned into an Escherichia coli expression vector, and myostatin proteins were expressed. Recombinant myostatin purified by electro-elution of th...

OBJECTIVES Atherosclerosis is the main leading cause of cardiovascular diseases. The purpose of this study was to assess the potential preventive effect of egg yolk HDL on the atherosclerosis plaque formation. MATERIALS AND METHODS Thirty rabbits were divided into five groups: A; normal diet, B; hyper-cholesterolemic diet, C; hypercholesterolemic + 400 mg/kg egg yolk HDL D; hypercholesterolem...

Males and females are in conflict over parental care, as it would be favourable for one parent to shift labour to the other. Yolk hormones may offer a mechanism through which female birds could influence offspring traits in ways that increase the relative investment by the male. We studied the role of yolk androgens in mediating sexual conflict over parental care in the collared flycatcher (Fic...

The aspect of the oogonia during their premitotic DNA synthesis and of the premeiocytes during their premeiotic DNA synthesis was studied in turtles by autoradiography, after injection of 3H-thymidine. As in the adult laying quail, the intrafollicular oocytes of the adult turtle go through three successive stages: prelampbrush, lampbrush and postlampbrush. During the prelampbrush and lampbrush ...

A completely randomized design experiment was conducted to evaluate the effect of feeding different levels (0, 2.5, 5.0, 10.0, 20.0%) of guar meal (GM) in laying hen diets over a 8-wk trial period. A total of 180 Hisex laying hens (25wk old) of similar body weight were randomly distributed among 5 treatments with 6 replicates with 6 hens each. Body weight, body weight gain, egg produced per hen...

A 3 x 3 treatment arrangement varying in dietary protein and TSAA:Lys was used to evaluate the effect of low-protein diets fed to Hy-Line W-98 laying hens. Phase I was 20 to 43 wk of age with 18.9, 17.0, and 14.4 g of protein/hen per day and 0.97, 0.85, and 0.82 TSAA:Lys, whereas phase II was 44 to 63 wk of age with 16.3, 14.6, and 13.8 g of protein/hen per day and 0.92, 0.82, and 0.72 TSAA:Lys...

This study aimed to investigate the effects of sumac fruit powder (SFP; Rhus coriaria L.) supplementation on productive performance, egg quality traits and serum biochemical parameters in old laying hens. One-hundred-twenty, 54 weeks Hy-line W36 strain-laying hens were assigned three treatments, five replicates eight per replicate a completely randomised design. Experimental diets included: (1)...

OBJECTIVE To assess whether incubation in TEST-yolk buffer (TYB) or human tubal fluid (HTF) could alter the sperm membrane characteristics and its relationship to antisperm antibodies (ASA) and/or antigen detachment from the sperm membrane and to evaluate the filtration of those specimens and possible recovery of ASA-free spermatozoa. DESIGN A prospective clinical study. SETTING Andrology I...

A study was conducted to determine the effect of feeding high concentrations of corn distillers dried grains with solubles (DDGS) on egg production and the internal quality of eggs from laying hens. Four diets were formulated to contain 0, 17, 35, or 50% corn DDGS. A total of two hundred forty 54-wk-old Single-Comb White Leghorn laying hens were randomly allotted to 2 birds per cage with 3 cons...