Storing hatchable eggs is a common practice in commercial hatcheries. However, storage time may negative effects on several performance parameters. An experiment was carried out to evaluate inverting egg position during storage of eggs laid by young and old layer breeders. Fertile eggs of 32 and 58-week-old breeders were stored for seven, 14, and 21 days at 18ºC ± 2ºC and 80% ± 10% relative humidity (RU). The following parameters were evaluated: egg weight loss, hatchability and hatchling weight, and embryodiagnosis results. Eggs stored with the small end up lost less weight during storage compared with the control eggs. Storing eggs for 14 days with the small end up reduced early embryo mortality, improving hatchability. In addition, hatchling weight increased. These results show that the detrimental effects of long storage periods may be alleviated when eggs are stored with the small end up to 14 days of storage
Campylobacter sp is an important agent that causes foodborne infection, particularly in food of poultry origin. Therefore, the efficient control of the transmission routes in chicken farms is of outmost importance to prevent it from spreading. In chicken farms, the main transmission route of this microorganism is horizontal, as the vertical route continues to be the object of inconclusive researches. The objective of this study was to verify the presence of Campylobacter sp in breeder hens, meconium, and other organs of day-old chicks derived from these breeders in order to obtain information on vertical transmission. Microbiological analyses were performed, using cloacal swabs from 279 breeder hens. Positive breeders were segregated, and the presence of Campylobacter sp. was verified in their progeny by analyzing 117 meconium samples; 36 heart, liver and spleen samples (pool of 3 day-old chicks per sample), and 34 intestine samples (pool of 3 chickens in each sample). The analysis of the 279 breeder hens showed that 39 (13.97%) were positive for Campylobacter sp, using the cloacal swab method. The meconium and the organs of day-old chicks were not positive. The physiological characteristics of breeder hens, of eggs, and of Campylobacter sp favor the entrance of bacteria and their survival inside the eggs, and therefore, this probably is the contamination route of day-old chicks. However, chick meconium and organs were negative in the present experiment, indicating that the vertical way of transmission is a rare event
The objective of this study was to evaluate the effect of recombinant bovine somatotropin (rbST) on average total weight gain, average daily gain, muscularity and finishing. 24 Nellore heifers were used, up to two years of age and weighing 307.4 kg. The animals were semi-confined in Brachiaria ruziziensis and were supplemented per day, with 1.5% kg live weight per animal feed. Heifers were divided into 2 groups, T1: with the use of rbST and T2: unused rbST (control). The rbST was applied every 14 days at a dose of 500 mg per animal. For the statistical analysis, the results were submitted to analysis of variance (ANOVA) at 5% significance level. There was no significant difference (p> 0.05) for average initial body weight, average final body weight, total average gain and average daily gain, and ribeye area (REA) adipose tissue thickness. Therefore the use of rbST did not promote change in performance characteristics in Nellore heifers 2 years old.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.