Responses to stunting syndrome (SS) infective material obtained from affected broilers and administered per os were monitored for 3 wk in a fast-growing commercial broiler population, in slow-growing Leghorn chicks, and in turkey poults. At 2 and 3 wk, the size of the gastrointestinal tract (GIT) segments, the pH of the GIT contents, and the activities of digestive enzymes in the intestinal con...

Out of 155 newly hatched SPF White Leghorn chicks, five chicks were randomly separated to confirm the SPF status of the chicks before inoculation. The remaining 150 chicks were divided into six groups. The three sacrificed groups (A, B and C) of 30 chicks each and their respective three mortality groups (MA, MB and MC) of 20 chicks each. The chicks in groups A and MA, and in groups B and MB wer...

Antibody responses to a first, second, and third injection with SRBC, and growth were studied in lines of White Leghorn chickens selected for high (HA) or low (LA) 5-d antibody titers to an i.v. inoculation with 0.1 mL of a 0.25% suspension of SRBC. The experiment involved parallel studies on two groups of chicks hatched from the same matings of parental lines HA and LA at a 14-d interval. Chic...

The efficacy of the commercial competitive exclusion product Broilact against Campylobacter jejuni was evaluated in broiler chickens in a 5-week pilot-scale study. Newly-hatched broiler chicks were brought from a commercial hatchery. After arrival 50 seeder chicks were challenged orally with approximately 10(3) cfu of C. jejuni, wing marked, and placed back in a delivery box and moved to a sepa...

PURPOSE To determine whether the muscarinic antagonist atropine effectively reduces or prevents experimentally induced myopia via a nonaccommodative mechanism. METHODS Chicks were monocularly deprived (MD) of pattern vision by placement of a translucent occluder over the left eye. In two of the three MD groups, chicks received a series of intravitreal injections of atropine (n = 8) or saline ...

In altricial and semi-altricial species, asynchronous hatching gives the first chicks to hatch an initial advantage over other siblings and often leads to the elimination of the smallest chicks. Both baseline corticosterone and acute stress-induced corticosterone levels have been shown to be higher in food deprived chicks than in chicks fed ad libitum. However, first-hatched chicks have also be...

Food intake in chickens is regulated in a manner similar to that in mammals. Corticotropin-releasing factor (CRF), which increases the plasma corticosterone concentration, plays an important role as a mediator of many appetite-suppressive peptides in the central nervous system in both species. Central administration of glucagon suppresses food intake in rats. However, the anorexigenic action of...

Two experiments were conducted to evaluate the effects of fusaric acid (FA) in broiler chicks (Exp. 1) and turkey poults (Exp. 2). In each experiment, 100 day-old birds were allotted randomly to dietary treatments containing 0, 100, 200, 300, or 400 mg FA/kg of feed. Each dietary treatment was fed to 4 pen replicates of 5 birds each for 21 days. Fusaric acid had no effect (P > 0.05) on feed int...

A wild strain of Eimeria tenella was isolated and utilized for immunization studies. Its optimal sporulation was attained at room temperature 24-25 degrees C after 24-48 h. Two groups of chicks were immunized by dosing a graded dose of five oocysts/chick/day for 6 days followed by 50 oocysts/chick/day for 7 days. A third group was not immunized and served as a negative control. Immunized chicks...

Maternal behavior has a significant individual variability, as mothers take care differently to their young based on their own breeding experience or age. In this parent-youth system, we investigated whether the young played a role as modulator of maternal behavior. For this, we evaluated how adoptive quail (unstressed) raised chicks coming from stressed female (PS) or not (NPS) thank a social ...