Two experiments were conducted to evaluate the effect of broiler breeder age and incubator type on hatching parameters, hatch window, embryo diagnosis results, and hatchling physical quality. The treatments consisted of a combination of three broiler breeder ages (29, 35 and 59 weeks of age) and two incubator types (single stage, SS; or and multiple stage, MS). A completely randomized design in a 3x2 factorial arrangement was applied. In Experiment I, 1,896 eggs were used and 360 eggs in Experiment II. There was an interaction between breeder age and incubator type only for hatchling physical quality score. Independently of incubator type, hatchability rate, late embryo mortality, and egg contamination were higher in the eggs laid by older breeders (59-wk-old). Early mortality (0-4 days) was higher in the embryos from young breeders (29-wk-old). A shorter hatch window birth was obtained in the SS incubator, resulting in higher hatchling body weight relative to egg weight, and better hatchling physical quality score. Both types of incubators provide good conditions for embryo development; however, the physical quality of chicks derived from eggs from intermediate-aged breeders (35-wk-old) is better when eggs are incubated in SS incubators.

-The objective of this study was to evaluate a technique for quantifying eggshell conductance using shell fragments from hatched eggs. Additional objectives were to calculate the correlation between eggshell conductance, porosity, and thickness and correlate these parameters with incubation data. The study design was fully randomized in a 3 × 3 factorial scheme (three egg regions -large end, equator, and narrow end -and three ages of broiler breeders -29, 35, and 59 weeks). A total of 216 eggs were used, with 24 repetitions for each treatment. Neither conductance nor shell thickness showed any interaction with egg region. Breeder age influenced eggshell conductance, such that it was greatest in eggshells from 59-week breeders (0.323 mg day −1 torr −1 ), while for 29-week and 35-week breeders, the conductance values found were 0.285 and 0.270 mg day −1 torr −1 , respectively. The eggshell thickness was similar in eggs from 29 and 35-week breeders and these were greater than the thickness of eggshells from 59-week breeders. Correlations between mean eggshell conductance and chick body weight and yolk free chick body weight were found significant. There were no correlations between mean eggshell thickness and any of the data evaluated. There were positive correlations between mean eggshell porosity and egg weight loss up to the time of transfer, chick weight, and yolk free body weight. The technique of using eggshell fragments can be used for measuring eggshell conductance. Eggshell porosity is the characteristic that best correlates with incubation parameters.Key Words: fertile eggs, porosity, shell conductance, shell thickness Revista Brasileira de Zootecnia

Two experiments were conducted to evaluate the effect of including protected sodium butyrate (PSB) in the diets of laying hens of advanced age on productive performance and egg quality. In experiment 1, a total of 320 Dekalb White 61-week-old laying hens were distributed in a randomized block design to four treatments (0, 105, 210, and 300 g/ton of PSB) with eight replicates of 10 birds. The experiment was conducted over 112 days, divided into four periods of 28 days each. Productive performance and egg quality were evaluated. In experiment 2, a total of 58 000 Dekalb White 70-week-old laying hens were assigned to diets containing either 0 or 105 g/ton of PSB with two replicates of 14 500 birds. The experiment was conducted on a commercial poultry farm. Egg production and the percentages of broken eggs and dirty eggs were evaluated. The PSB levels did not influence the productive performance of laying hens. A quadratic effect was observed for eggshell thickness, percentage of eggshell and eggshell strength, reaching maxima at 193, 136 and 198 g/ton of PSB, respectively. A quadratic effect on yolk index reached a minimum at 181 g/ton of PSB. The percentages of dirty eggs and broken eggs were lower in laying hens fed 105 g/ton of PSB. In conclusion, the addition of PSB to the diets of old laying hens improved the eggshell quality and decreased the percentage of broken and dirty eggs Keywords: egg quality, laying hens, organic acids, performance, protected sodium butyrate

Two experiments were carried out to evaluate the effect of using soy protein concentrate (SPC) in pre-starter and starter diets for broilers. In the first experiment, 600 male Cobb broilers, between one and 40 days of age, were distributed in a completely randomized design, with four treatments and six replications of 25 birds each. Treatments were ofered to broilers in the pre-starter and starter diets and consisted of inclusion of soy protein concentrate (0,3,6 and 9%) in diets. The parameters evaluated were: body weight gain, feed conversion ratio, consumption of ration, enzyme production in the pancreas, villus: crypt ratio, leukocyte count and immunoglobulin A (IgA) dosage. Aimed to determine the coefficient of nutrient metabolization of feeds, 144 male Cobb chicks were distributed, between 14 and 21 days of age, with four treatments and six replications of six birds per experimental unit. Treatments were the same as in the first experiment. The use of 3 and 9% of SPC did not affect weight gain, feed intake, feed conversion or viability of the poultry. The use of 6% of SPC provided an increase in trypsin activity, villi length and crypt depth; the coefficient of dry matter metabolization increased linearly; but no differences were observed in performance or immunological parameters.

In ovo feeding has been indicated to improve hatchability, newly hatched chick quality, and broiler performance. The aim of this study was to investigate the effect of in ovo feeding of a commercial canthaxanthin product ( CCX ) containing lignosulphonate, corn starch, canthaxanthin, dextrin (yellow), and ethoxyquin through assessing incubation results, newly hatched quality and oxidation status and broiler performance at 1 to 14 d of age. A total of 780 egg were distributed in a randomized complete block design with 5 treatments (levels of CCX: 0.0, 0.35, 0.45, 0.55, and 0.65 mg/0.5 mL of sterilized and distilled water) and 156 eggs per treatment. The blocking factor was setters. At 17.5 d of embryo development, in ovo injected treatments were applied, using a manual needle. The in ovo feeding of CCX resulted in lower hatching rates ( P < 0.05) and a longer hatching window ( P < 0.05) as compared with noninjected CCX treatment. The CCX injection did not affect the bursa and spleen percentage of newly hatched chick ( P > 0.05). In addition, a higher percentage of chicks with poor physical quality score (<71.0 points) was obtained among the chicks from eggs injected with 0.55 and 0.65 mg of CCX ( P < 0.05). There were higher total proteins and catalase activity in the livers of the chicks injected with CCX. Broiler chicks in the control group (0.0 mg of CCX) presented higher BW and BW gain during 1 to 7 and 7 to 14 d of after hatch ( P < 0.05). The viability (%) of chicks at 1 to 14 d of after hatch decreased with inoculation greater than 0.45 mg of CCX in ovo ( P < 0.05). Although the CCX shown an improvement in oxidation status of chicks, the hatchability and performance of broilers decreased. We concluded that a commercial CCX is not recommended for injection in ovo, and furthers studies should carried out to elucidate the use of pure canthaxanthin.