ABSTRACT This experiment aimed to evaluate the utilization of firewood ash as calcium source in the initial diet of broiler chickens. One hundred and twenty eight broiler chickens of Cobb-500® strain, from 1 to 21 days of age, were randomly distributed in four treatments with four repetitions of eight birds each, been four female and four male. The experimental diets were corn-soybean based, been isoenergetic and isonutrients, and had 0, 0.32, 0.98 and 1.27% of firewood ash as calcium source. The firewood ash utilized had 23.8% of calcium, 0.39% of total phosphorus, and 0.11% of sodium. The experimental treatments did not influence the feed intake, body weight, body weight gain, and food conversion from 1 to 7, 1 to 14, and 1 to 21 days of age. The tibia and femur thickness and length at 21 days of age were not altered by treatments. It was concluded that the firewood ash can be used as calcium sourcereplacing limestone in the initial diet of broiler chickens, without change the performance and the bone development.

Abstract The objective of the present study was to evaluate the effect of the dietary detoxified castor seed cake (DCC) inclusion on broiler performance and carcass traits. Two hundred and fifty Cobb-500(r) broilers were distributed according to a completely randomized experimental design consisting of five treatments (dietary inclusion of 0.0, 2.5, 5.0, 7.5, and 10.0% DCC) with five replicates of 10 birds each (five males and five females). Feed intake (FI), body weight gain (WG), and feed conversion ratio (FCR) were evaluated from one to 40 days of age. Carcass yield and the yields of the breast, leg (drumstick+thighs), and wings were determined when broilers were 40 days old. Live performance parameters were influenced by DCC dietary inclusion, and levels 2.00, 1.38, and 1.25% DCC impaired FI, WG, and FCR, respectively. Carcass and parts yields were not affected by dietary DCC inclusion. It was concluded that the addition of DCC levels up to 1.25% to broiler diets does not impair live performance or carcass traits.

Dose-dependent positive effects on hatchability and hatchling weight have been attributed to ascorbic acid (AA) when eggs were submitted or not to intermittent heat stress during incubation. Fertile breeder (Cobb(r)) eggs were used to determine if the pre-incubation injection of AA in ovo affects the incubation and hatchling quality of egg incubated under thermoneutral or intermittent heat stress conditions. Eggs were not injected or injected with 0, 2,4, or 6% AA/100µL water and incubated at continuous thermoneutral (37.5ºC) or hot (39.0ºC) temperature. Eggshell temperature (EST) increased in the second half of the incubation period in all experimental groups. The EST of non-injected eggs and of those injected with water was higher when incubated at 39°C than at 37.5°C, but EST was not different among eggs injected with AA. Egg mass loss and eggshell conductance were higher in the eggs incubated at 39°C than at 37.5°C.Hatchability was lower in the eggs injected with AA. Liver and yolk sac weights were higher, whereas heart and liver weights were lower in hatchlings from eggs incubated at 39°C; however, hatchling weight was not affected by incubation temperature. The results showed that AA doses affected egg conductive heat loss and hatchability, and that they did not minimize the effects of high incubation temperature on liver and heart development.

This study aimed at determining a specific classification of coefficients of variation in experiments with commercial layers. Coefficients of variation were collected from papers published in Brazilian journals between 2000 and 2009 for performance, internal egg quality, and eggshell quality parameters. The coefficients of variation of each parameter were classified as low, intermediate, high, and very high according to the ratio between the median and the pseudo-sigma. It was concluded that the parameters used in experiments with commercial layers have a specific classification of coefficients of variation, and that this must be considered to evaluate experimental accuracy.