Single-Step Methodology for Genomic Evaluation in Turkeys ().

Genomic information can contribute significantly to the increase in accuracy of genetic predictions compared to using pedigree relationships alone. The main objective of this study was to compare the prediction ability of pedigree-based best linear unbiased prediction (PBLUP) and single-step genomic BLUP (ssGBLUP) models. Turkey records of feed conversion ratio, residual feed intake, body weight, breast meat yield, and walking ability were provided by Hybrid Turkeys, Kitchener, Canada.

Identification of protein-damaging mutations in 10 swine taste receptors and 191 appetite-reward genes.

Background: Taste receptors (TASRs) are essential for the body's recognition of chemical compounds. In the tongue, TASRs sense the sweet and umami and the toxin-related bitter taste thus promoting a particular eating behaviour. Moreover, their relevance in other organs is now becoming evident.

Identification of genetic variation in the swine toll-like receptors and development of a porcine TLR genotyping array.

Background: Toll-like receptors (TLR) are crucial in innate immunity for the recognition of a broad range of microbial pathogens and are expressed in multiple cell types. There are 10 TLR genes described in the pig genome.

Results: With a twofold objective i.

Regional differences in recombination hotspots between two chicken populations.

Background: Although several genetic linkage maps of the chicken genome have been published, the resolution of these maps is limited and does not allow the precise identification of recombination hotspots. The availability of more than 3.2 million SNPs in the chicken genome and the recent advances in high throughput genotyping techniques enabled us to increase marker density for the construction of a high-resolution linkage map of the chicken genome.

Hypothalamic control of the thyroidal axis in the chicken: over the boundaries of the classical hormonal axes.

The pituitary gland, occupying a central position in the hypothalamo-pituitary thyroidal axis, produces thyrotropin (TSH), which is known to stimulate the thyroid gland to synthetize and release its products, thyroid hormones. TSH is produced by a specific cell population in the pituitary, the so-called thyrotropes. Their secretory activity is controlled by the hypothalamus, releasing both stimulatory and inhibitory factors that reach the pituitary through a portal system of blood vessels.

Effects of dietary macronutrient content on energy metabolism and uncoupling protein mRNA expression in broiler chickens.

The objective of the present study was to investigate the effects of dietary macronutrient ratio on energy metabolism and on skeletal muscle mRNA expression of avian uncoupling protein (UCP), thought to be implicated in thermogenesis in birds. Broiler chickens from 2 to 6 weeks of age received one of three isoenergetic diets containing different macronutrient ratios (low-lipid (LL) 30 v. 77 g lipid/kg; low-protein (LP) 125 v.

Cold-induced enhancement of avian uncoupling protein expression, heat production, and triiodothyronine concentrations in broiler chicks.

The relationships among avian uncoupling protein (avUCP) mRNA expression, heat production, and thyroid hormone metabolism were investigated in 7-14-day-old broiler chicks (Gallus gallus) exposed to a low temperature (cold-exposed chicks, CE) or a thermoneutral temperature (TN). After 7 days of exposure, CE chicks exhibited higher heat production (+83%, P<0.01), avUCP mRNA expression (+20%, P<0.

Pre- and postprandial changes in plasma hormone and metabolite levels and hepatic deiodinase activities in meal-fed broiler chickens.

The present study aimed to study the effects of food deprivation and subsequent postprandial changes in plasma somatotrophic and thyrotrophic hormone levels and focused on the inter-relationships between these hormonal axes and representative metabolites of the intermediary metabolism of meal-fed broiler chickens. Male broiler chickens (2 weeks old) were fed a meal of 40-45 g/bird per d for two consecutive weeks (food-restricted (FR) treatment). The daily allowance was consumed in about 30 min.

Thyroid status, but not insulin status, affects expression of avian uncoupling protein mRNA in chicken.

The aim of this study was to investigate the hormonal regulation of the avian homolog of mammalian uncoupling protein (avUCP) by studying the impact of thyroid hormones and insulin on avUCP mRNA expression in chickens (Gallus gallus). For 3 wk, chicks received either a standard diet (control group), or a standard diet supplemented with triiodothyronine (T(3); T3 group) or with the thyroid gland inhibitor methimazole (MMI group). A fourth group received injections of the deiodinase inhibitor iopanoic acid (IOP group).

Developmental endocrinology of the reproductive axis in the chicken embryo.

In mammals, the phenotype of the homogametic sex develops in the (relative) absence of steroids and the phenotype of the heterogametic sex is imposed by the early action of steroids. In contrast, the heterogametic sex in avian species is the female and the presence of estrogens and their receptors plays a crucial role in female sexual differentiation. The time- and sex-dependent expression of enzymes involved in steroidogenesis which determine the ratio of androgens/estrogens produced by the gonads has been extensively investigated during the last 5-6 years.