Circulation of Major Respiratory Pathogens in Backyard Poultry and their Association with Clinical Disease and Biosecurity

Raising backyard birds is a common practice in Brazil, mainly in the countryside or suburban areas. However, the level of respiratory pathogens in these animals is unknown. We sampled two hundred chickens from 19 backyard flocks near commercial poultry farms and performed ELISA to Infectious Bronchitis Virus, avian Metapneumovirus, Mycoplasma synoviae and Mycoplasma gallisepticum. We evaluated the association between the predictive ability of ELISA and Hemagglutination-inhibition (HI)by comparing results from eight flocks positive to Mycoplasma gallisepticum on ELISA. Besides, we assessed essential biosecurity measures in the properties (multiple species birds, rodent control, hygienic conditions, and water quality for the bird`s consumption). We could access the vaccination program only on four properties; in three of them, the birds were supposedly vaccinated for IBV. Overall the properties had a poor score for the biosecurity measures, and the seroprevalence in backyard poultry flocks for IBV, a MPV, MS, and MG were respectively 87.5% (14/16), 89.5% (17/19), 100 (19/19) and MG 84.21% (16/19). We found low specificity and predictive value between ELISA and HI in MG analysis and a positive correlation between the presence of clinical symptoms and mean MG titers. Backyard chicken are pathogens reservoirs and pose a risk for the commercial poultry farms in the region, and further efforts of the governmental entities and private sector of poultry production should consider these information to avoid future economic losses.(AU)

Circulation of Major Respiratory Pathogens in Backyard Poultry and their Association with Clinical Disease and Biosecurity

Raising backyard birds is a common practice in Brazil, mainly in the countryside or suburban areas. However, the level of respiratory pathogens in these animals is unknown. We sampled two hundred chickens from 19 backyard flocks near commercial poultry farms and performed ELISA to Infectious Bronchitis Virus, avian Metapneumovirus, Mycoplasma synoviae and Mycoplasma gallisepticum. We evaluated the association between the predictive ability of ELISA and Hemagglutination-inhibition (HI)by comparing results from eight flocks positive to Mycoplasma gallisepticum on ELISA. Besides, we assessed essential biosecurity measures in the properties (multiple species birds, rodent control, hygienic conditions, and water quality for the bird`s consumption). We could access the vaccination program only on four properties; in three of them, the birds were supposedly vaccinated for IBV. Overall the properties had a poor score for the biosecurity measures, and the seroprevalence in backyard poultry flocks for IBV, a MPV, MS, and MG were respectively 87.5% (14/16), 89.5% (17/19), 100 (19/19) and MG 84.21% (16/19). We found low specificity and predictive value between ELISA and HI in MG analysis and a positive correlation between the presence of clinical symptoms and mean MG titers. Backyard chicken are pathogens reservoirs and pose a risk for the commercial poultry farms in the region, and further efforts of the governmental entities and private sector of poultry production should consider these information to avoid future economic losses.

Feeding management strategy for male broiler breeders and its effects on body weight, hatchability and fertility

The objective of the present study was to evaluate the supply of a specific-male diet on rooster body weight, hatchability, and fertility. Two diets were supplied during the egg production period: treatment 1, diet formulated for females and containing, in average, 2,830 kcal ME/kg and 15% CP; and treatment 2, diet specifically formulated for male broiler breeders, containing 2,750 kcal ME/kg and 13.5% CP. In the experiment, 26 flocks, with approximately 7,000 females and 840 males each, belonging to the same broiler breeder commercial strain, were distributed into 26 houses (1200m²) on the same farm, and submitted to the same management practices. Body weight was evaluated in 13 flocks per treatment and for five weeks (45, 50, 55, 60, 65), and hatchability and fertility in four incubation lots per treatment and for the same weeks. Data were evaluated by the analysis of mixed models for repeated measurements, using the PROC MIXED of SAS 9.3 (SAS Institute Inc., Cary, NC, USA), and means were compared by the test of Tukey-Kramer at 5% significance level. The specific-male diet allowed body weight control during all analyzed weeks and promoted high hatchability and egg fertility. The increase in the number of chicks hatched demonstrates the economic viability of feeding a specific diet for male broiler breeders.

Feeding management strategy for male broiler breeders and its effects on body weight, hatchability and fertility

The objective of the present study was to evaluate the supply of a specific-male diet on rooster body weight, hatchability, and fertility. Two diets were supplied during the egg production period: treatment 1, diet formulated for females and containing, in average, 2,830 kcal ME/kg and 15% CP; and treatment 2, diet specifically formulated for male broiler breeders, containing 2,750 kcal ME/kg and 13.5% CP. In the experiment, 26 flocks, with approximately 7,000 females and 840 males each, belonging to the same broiler breeder commercial strain, were distributed into 26 houses (1200m²) on the same farm, and submitted to the same management practices. Body weight was evaluated in 13 flocks per treatment and for five weeks (45, 50, 55, 60, 65), and hatchability and fertility in four incubation lots per treatment and for the same weeks. Data were evaluated by the analysis of mixed models for repeated measurements, using the PROC MIXED of SAS 9.3 (SAS Institute Inc., Cary, NC, USA), and means were compared by the test of Tukey-Kramer at 5% significance level. The specific-male diet allowed body weight control during all analyzed weeks and promoted high hatchability and egg fertility. The increase in the number of chicks hatched demonstrates the economic viability of feeding a specific diet for male broiler breeders.(AU)

Effects of inverting the position of layers eggs during storage on hatchery performance parameters

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.(AU)