Is the eggshell quality influenced by the egg weight or the breeder age?

For a long time, it has been said that eggshell quality decreases as eggs increase in size, but this increase is seen as the breeder age advances. Therefore, the present study aimed to evaluate the age and egg weight effect on Cobb 500 broiler breeders on eggshell quality. The quality measures tested were eggshell and mineral matter percentage, eggshell surface, shape and eggshell index, eggshell and membrane thickness and specific gravity. Eggs from 27, 31, 36, 40, 46, 48, 53, 58 and 63 week-old breeders were classified as eggs with a constant weight ranging from 63.8 ± 0.2; and eggs with increasing weight, according to age, being: 55.8g; 60g; 62.2g; 64.2g; 65.2g, 66.6g, 68.1g, 69.9g and 72.5g, respectively. The eggs weight did not influence the eggshell percentage and the specific gravity in seven of the nine tested ages, while for mineral matter in six of the nine studied ages. The shape and shell index, shell and membrane thickness are characteristics independent of egg weight. As the Cobb 500 broiler breeder age advanced, the mineral matter concentration and specific gravity maintained constant, the membrane thickness (R2>70) reduced, and other studied variables were influenced in the same way for both treatments. Thus, the eggshell quality decrease with the advancing age cannot be attributed solely to the increase of egg weight with consequent increase in the eggshell volume and the surface, but there are also age-related factors.(AU)

Is the eggshell quality influenced by the egg weight or the breeder age?

For a long time, it has been said that eggshell quality decreases as eggs increase in size, but this increase is seen as the breeder age advances. Therefore, the present study aimed to evaluate the age and egg weight effect on Cobb 500 broiler breeders on eggshell quality. The quality measures tested were eggshell and mineral matter percentage, eggshell surface, shape and eggshell index, eggshell and membrane thickness and specific gravity. Eggs from 27, 31, 36, 40, 46, 48, 53, 58 and 63 week-old breeders were classified as eggs with a constant weight ranging from 63.8 ± 0.2; and eggs with increasing weight, according to age, being: 55.8g; 60g; 62.2g; 64.2g; 65.2g, 66.6g, 68.1g, 69.9g and 72.5g, respectively. The eggs weight did not influence the eggshell percentage and the specific gravity in seven of the nine tested ages, while for mineral matter in six of the nine studied ages. The shape and shell index, shell and membrane thickness are characteristics independent of egg weight. As the Cobb 500 broiler breeder age advanced, the mineral matter concentration and specific gravity maintained constant, the membrane thickness (R2>70) reduced, and other studied variables were influenced in the same way for both treatments. Thus, the eggshell quality decrease with the advancing age cannot be attributed solely to the increase of egg weight with consequent increase in the eggshell volume and the surface, but there are also age-related factors.

Comparison of the effect of hatchery disinfection with peracetic acid andglutaraldehydeassociated with quaternary ammonia compounds on the tracheal mucosa of one day old chicks

This study aimed at identifying lesions in the respiratory tract of chickenscaused by hatchery disinfection, performed by micro-sprinkler withperacetic acid and ammonia associated with glutaraldehyde. Theexperiment was conducted at a hatchery in Uberlândia - MG, in June2013. Three hatcheries were employed, each one using a differenttreatment process. All process had been conducted in the same room andhad the same mechanisms of temperature, humidity and ventilationcontrol. Process 1 (P1) was sprayed with a solution of peracetic acid (twoml per liter of water, total of 300 ppm); P2 was sprayed with a solution ofglutaraldehyde associated with ammonia (one ml of water per liter, total of450 and 75 ppm); and P3 was sprayed only with distilled water. At the endof 48 hours, 16 chicks per treatment process were collected at eachoutbreak to remove the trachea. Each trachea was divided into twosamples. One sample was processed for evaluation by optical microscopeand another was processed for evaluation by transmission electronmicroscope. The observation of the slides had 10 fields for evaluation, sothat all tracheal mucosa on each slide was observed for the definition ofscores according to the degree of the found lesions. At the result, there wasa significant difference only in the material evaluated by light microscopybetween chicks exposed to environmental ammonia and glutaraldehyde(P2) related to the control group (P3), considering that these chicks showedmore severe injuries, such as areas with less cilia and areas of trachealmucosa flaking. Chicks exposed to disinfection with peracetic acid inhatcheries did not show lesions of the tracheal mucosa. Therefore, whenusing the dosages in this study, peracetic acid can be used for thedisinfection of hatcheries to reduce the contamination present during theprocess, while causing less damage to the tracheal mucosa of chicks.(AU)

Comparison of the effect of hatchery disinfection with peracetic acid andglutaraldehydeassociated with quaternary ammonia compounds on the tracheal mucosa of one day old chicks

This study aimed at identifying lesions in the respiratory tract of chickenscaused by hatchery disinfection, performed by micro-sprinkler withperacetic acid and ammonia associated with glutaraldehyde. Theexperiment was conducted at a hatchery in Uberlândia - MG, in June2013. Three hatcheries were employed, each one using a differenttreatment process. All process had been conducted in the same room andhad the same mechanisms of temperature, humidity and ventilationcontrol. Process 1 (P1) was sprayed with a solution of peracetic acid (twoml per liter of water, total of 300 ppm); P2 was sprayed with a solution ofglutaraldehyde associated with ammonia (one ml of water per liter, total of450 and 75 ppm); and P3 was sprayed only with distilled water. At the endof 48 hours, 16 chicks per treatment process were collected at eachoutbreak to remove the trachea. Each trachea was divided into twosamples. One sample was processed for evaluation by optical microscopeand another was processed for evaluation by transmission electronmicroscope. The observation of the slides had 10 fields for evaluation, sothat all tracheal mucosa on each slide was observed for the definition ofscores according to the degree of the found lesions. At the result, there wasa significant difference only in the material evaluated by light microscopybetween chicks exposed to environmental ammonia and glutaraldehyde(P2) related to the control group (P3), considering that these chicks showedmore severe injuries, such as areas with less cilia and areas of trachealmucosa flaking. Chicks exposed to disinfection with peracetic acid inhatcheries did not show lesions of the tracheal mucosa. Therefore, whenusing the dosages in this study, peracetic acid can be used for thedisinfection of hatcheries to reduce the contamination present during theprocess, while causing less damage to the tracheal mucosa of chicks.