Concerns regarding the welfare of laying hens raised in battery cages have led to the development of enriched cages that allow hens to perform natural behaviors including nesting, roosting, and scratching. This study was conducted to compare indices of production and welfare in birds housed in 2 different caging systems. Shaver White hens were housed from 21 to 61 wk in either conventional batt...

The purpose of this study was to evaluate cytologically the bone marrow (and peripheral blood) of adult laying hens affected with lymphoid leukosis. Diagnosis of the neoplasm was made on the basis of clinical history, signs and symptoms and pathology. Only histologically confirmed cases were included in the study. Examination of blood smears revealed +2 heterophil toxicity and the presence of l...

The identification of infected commercial poultry flocks has become a pivotal component of efforts to reduce the incidence of egg-associated transmission of Salmonella enteritidis to humans. To assess the sensitivity with which testing for specific antibodies in egg yolks can be applied to detect S. enteritidis infection in laying chickens, groups of hens were orally inoculated with either 10(3...

Ad libitum feeding causes excessive follicular development and is associated with extensive metabolic changes in broiler-breeder hens. Restricting feed intake reduces excessive follicular development, but the mechanisms mediating this response are unknown. In the present study, the effects of feeding on follicular development in immature broiler-breeder hens were examined. There was an increase...

The pecking behavior [severe feather, gentle feather, and aggressive pecks (AP)] of individual White Shaver non-cage laying hens (n = 300) was examined at 21, 24, 27, 32, and 37 weeks. Hens were housed in 30 groups of 10 hens each and on 3 cm litter with access to a feeder, perch, and two nest boxes. The number of severe feather pecks given (SFPG) and received (SFPR) was used to categorize hens...

3.1.0 Introduction: Heat exchanger network synthesis (HENS) is an important field in thermal engineering and has been the subject of a considerable amount of research over the past 50 years. Its significance can be attributed to its role in controlling the costs of energy for a process. The heat-exchanger network (HEN) design problem was introduced into the literature by Ten Broeck in 1944. The...

Long-term feed withdrawal has been shown to increase ileocecal intestinal colonization and fecal shedding of Salmonella enterica serovar Enteritidis in challenged hens. Less information is available regarding effects of fasting on crop colonization. Two trials were conducted to compare effects of 14-day feed withdrawal vs. full feed on crop colonization in hens challenged with Salmonella Enteri...

Female mutant restricted ovulator (RO) chickens of the White Leghorn strain carry a naturally occurring single nucleotide mutation in the very low density lipoprotein receptor (VLDLR) gene. Due to this mutation, RO hens fail to express a functional VLDLR protein on the oocyte membrane, which results in an impaired uptake of circulating yolk precursor macromolecules. Mutant RO hens subsequently ...

The effectiveness of diatomaceous earth (DE) as a treatment against parasites and to increase feed efficiency and egg production of organically raised free-range layer hens was evaluated in 2 breeds of commercial egg layers [Bovan Brown (BB) and Lowmann Brown (LB)] that differ in their resistance to internal parasitic infections. Half the hens of each breed were fed diets supplemented with DE (...

A study was conducted to examine the effects of diets supplemented with organic selenium, (Se) and zinc, (Zn) on the performance of Cochin exotic breeder hens. Forty-two week old hens (n=120) and males (n=12) were assigned to four treatment groups of 10 females and 1 male each. Birds with no mineral supplementation (Group 1); feed supplemented with .33 ppm Se (Group 2) feed supplemented with 20...