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Effect of antibiotic supplementation on growth performances in chickens in Zaire comparison with effects in temperate areas. The influence of different antibiotics, bacitracine (50 mg per kg), virginiamycine (20 mg per kg) and avoparcine (15 mg per kg) was tested on growth and feed conversion of chickens from a double purpose line under warm wet tropical conditions. In general, the beneficial effect of additives was much more pronounced in this experiment compared to data with identical doses of bacitracine and viriginiamycine in temperate areas. However this was hardly the case for avoparcine, indicating an interaction between the environment and the nature of antibiotic agent.

Onagbesan O. M., V. Bruggeman, P. Van As, K. Tona, J. Williams, and E. Decuypere. BMPs and BMPRs in chicken ovary and effects of BMP-4 and -7 on granulosa cell proliferation and progesterone production in vitro. Am J Physiol Endocrinol Metab 285: E973-E983, 2003. First published July 29, 2003; 10.1152/ajpendo.00104.2003.--Bone morphogenetic proteins (BMPs) and their receptors (BMPRs) are now known to have important roles in mammalian ovarian folliculogenesis. This study determined the expression of the mRNA encoding for BMPs and their receptors in the chicken ovary and explored possible roles for them. The expression of the mRNA for BMP-2, -4, -6, -7, and BMPR-IA, -IB, and -II was determined and quantified by a semiquantitative RT-PCR. The mRNAs for all the BMPs and receptors determined were present in both the granulosa (G) and theca (T) cells of the F1, F2, and F3 follicles. All BMP mRNAs increased in G cells with follicular development, whereas only BMP-7 mRNA had this trend in the T cells. BMP-2, -4, and -6 mRNAs in T were similar between follicles. BMPR-IA mRNA was similar in F2G and F3G but lower in F1G. BMPR-IB mRNA was similar in G of all follicles, and BMPR-II mRNA increased with development. In the T, each receptor subtype showed equal distribution between follicles. mRNA levels for BMPR-IB and -II were higher in G than in T, suggesting that the G is a major target for BMPs. BMP-4 and -7 stimulated basal, IGF-I-, and gonadotropin-stimulated progesterone production by cultured G cells, with differential responses between cells from the F1 and F3/4. This suggests involvement in follicular differentiation. BMP-4 and -7 reversed the inhibitory effects of transforming growth factor (TGF)-[alpha] on basal and gonadotropin-stimulated G cell progesterone production, with greater effect in the F1 than in the F3/4. This effect suggests an important role for BMPs interacting with TGF-[alpha] in modulating the effects of gonadotropins and IGF-I on follicular differentiation. Finally, BMP-7 stimulated G cell proliferation, but BMP-4 inhibited TGF-[alpha] + IGF-I- and/or FSH-stimulated G cell proliferation, suggesting a role in the control of follicular growth during development. These effects of BMP-4 and -7 on the G cell function showed relationships with the expression levels of the BMPs and the BMPR-II. chicken; bone morphogenetic proteins; bone morphogenetic protein receptors; theca; steroidogenesis

Two transport experiments were carried out with 18 pigs each. These pigs originated from three genetic lines (homozygous halothane-positive and -negative and heterozygotes). Half the pigs were unfed for 12 h before transport. All pigs were transported twice for 2 h. Before and after transport pigs were anesthetized to take blood samples from the jugular vein and biopsies from the biceps femoris. At the same time equipment to measure body temperature and heart rate were attached or detached. Plasma cortisol and beta-endorphin concentrations were measured as well as the glycogen concentration in the muscle sample. Line differences were detected with respect to body temperature (P [is less than] .04), heart rate (P [is less than] .05), and cortisol (P [is less than] .01). The withholding of feed influenced (P [is less than] .04) plasma beta-endorphin concentration. Body temperature (P [is less than] .02), heart rate (P [is less than] .001), cortisol (P [is less than] .01), and beta-endorphin (P [is less than] .001) were different before and after transport, whereas a training effect of the transport number was observed for heart rate (P [is less than] .07) and plasma beta-endorphin (P [is less than] .02). No interactions between treatments were observed. The relationship between cortisol and beta-endorphin suggests a nonconcomitant release of ACTH and beta-endorphin.

Manihot esculenta leaf meal in feed at post-hatch improves growth and egg production. One may question the efficacy of Manihot esculenta leaf extract for in ovo feeding. This study was conducted to determine the effects of in ovo injection of Manihot esculenta extract on hatchability, growth performance and biochemical parameters of Sasso broiler chickens. The hatching eggs from 38-week-old broiler breeders were set and at d 18 of incubation, 600 eggs with evidence of living embryos were assigned to 4 treatment groups of 150 eggs each. These groups were: (1) eggs without in ovo injection (negative control); (2) eggs perforated but no injection of any additive (positive control); (3) eggs perforated and injected with 0.1 ml of saline solution and (4) eggs perforated and injected with 0.1 ml of Manihot esculenta extract. Data were collected on hatching performance. During the post hatch growth phase, performance traits such as feed intake, weight gain, and feed conversion ratio were collected and at 84 days of age, blood samples were taken for determination of serum total proteins, triglycerides, aspartate aminotransferase (ASAT) and alanine amino transaminase (ALAT). The results showed that hatchability was similar in the negative control and Manihot esculenta extract groups but significantly higher (P < 0.05) than those of positive control and saline solution treatment groups. Chick quality was better in the groups with Manihot esculenta extract and saline solution application. Post-hatch, the body weight gain of birds from the Manihot esculenta extract group was higher than those in the groups with saline solution application and in the negative control and positive control groups. Manihot esculenta leaf extract increased significantly the triglyceride rate and reduced ALAT and ASAT concentration at hatch. It can be concluded that in ovo inoculation of 0.5 μg/ml Manihot esculenta leaf extract on d 18 of incubation into the eggs air chamber improved hatchability, chick quality and post-hatch growth of broilers. [ABSTRACT FROM AUTHOR]