ABSTRACT This study described changes in the serum biochemistry, morphology of genital organs, long bone, and eggshell during the daily egg formation cycle in Japanese quails. Sixty quails (18-wk) were distributed in 6 groups according to hours post-oviposition (POV): 0 hr POV (16h00), 2 hrs POV (egg in magnum), and 4, 8, 14, and 20 hrs POV (egg in uterus). The magnum had higher relative weight before the next ovulation (20 and 0 hr POV), and its tubular glands showed functional variation through periods: abundant eosinophilic, PAS+, and negative Alcian blue secretion at 0 and 2 hrs, empty glands aspect at 4 hrs, and filled again at 20 hrs POV. Serum albumin and total Ca had the highest value in the 2 hrs group, and the lowest in 8 and 14 hrs groups. Egg-cycle period affected the Ca% of the medullar bone of the femur and tibiotarsus, with the lowest mean at 14 hrs POV (06h00), and the highest mean after oviposition (0 hr POV), showing the recovery of Ca stores in long bones for the next egg cycle. Analysis of the eggshell using scanning electron microscopy evidenced that palisade layer formation starts during the night (8-14 hrs POV), and most parts are secreted during the day period. In conclusion, eggshell secretion in light periods, high magnum activity and medullary bone Ca deposition during midday and afternoon, as well as the ovulation/oviposition in the afternoon, are the main characteristics of the distinct physiological aspects of the egg cycle in quails.

ABSTRACT Linoleic (LA, 18:2) and alpha-linolenic (ALA, 18:3) acids are omega-6 and omega-3 polyunsaturated fatty acids considered essential to human and animal health. The optimum LA/ALA ratio for the production of fertile eggs in Japanese quail breeders has been little investigated. Thus, this study aimed to assess the effects of LA/ALA ratio on productive performance, egg quality, serum biochemical profile, body composition, and organ weight in Japanese quail. A completely randomized design was used. Birds were distributed into five treatments consisting of different LA/ALA ratios (1.48:1, 4.57:1, 7.63:1, 10.69:1, and 13.75:1), obtained by adding soybean (LA) and flaxseed (ALA) oils to the feed. Productive performance and egg quality were assessed in three cycles of 28 days each. At the end of the experiment, the birds were slaughtered and evaluated for biochemical profile, genital organ weights, and body composition. Data were subjected to analysis of variance and regression (p<0.05). LA/ALA ratio had no effect on productive performance or egg quality. Blood cholesterol in females and males and total triglycerides in females showed a quadratic response. Breeders fed the highest level of flaxseed oil (1.48:1) had the best serum levels of cholesterol and total triglycerides. Live weight and relative organ weights were not influenced by LA/ALA ratio. Differences in ash and crude protein levels were observed between groups, with LA increasing the deposition of these nutrients. It was concluded that LA/ALA ratio didn’t affect productive performance or egg quality. However, based on the results of body composition, serum triglycerides, and cholesterol, it is recommended to use an LA/ALA ratio of 1.48:1 in diets.

ABSTRACT Adverse environmental conditions during rearing may negatively affect productivity and meat quality of the modern fast-growing broiler strains. Temperature manipulation during sensitive embryonic development periods may affect broilers' physiological responses to environmental conditions during rearing on commercial farms. The objective of this trial was to evaluate the effect of temperature manipulation during incubation and breeder age on the meat quality of male and female broilers submitted to heat stress during the pre-slaughter period. In this experiment, 1280 broiler chicks were distributed according to a completely randomized experimental design in a 2x2x2 factorial arrangement. Treatments consisted of two breeder ages (30 and 60 weeks), two temperature programs applied in the last four days of incubation (standard or high temperature), and sex (male and female). Birds were submitted to 32 °C for 48 hours before slaughter, on day 46.Meat quality parameters (pH, temperature, color, and weight loss) were evaluated. There was significant effect (p<0.05) of sex on meat redness (a*) and fat percentage, with females presenting higher values than males in both measurements. Males incubated at the higher temperature presented higher (p<0.05) meat weight loss by pressure than females. The thermal manipulation applied during the final stage of incubation did not affect the meat yield or meat quality of broilers submitted to heat stress.

The influence of age (85, 140, and 270 days) of European quails breeders on the egg quality and hatching, fertility and progeny performance was evaluated. The experimental design was completely randomized in a 3x3 factorial arrangement (females' age x males' age), with ten replicates and six birds per experimental unit (four females and two males). Egg production and quality were determined during 3 periods of 14 days and incubation parameters were evaluated in eggs obtained in five consecutive days. The live performance of the progenies was analyzed until 35 days. There was no effect of male age or any interaction between the age of males and females for the evaluated variable. The female's age influenced egg production, egg weight and chick weight, with better results obtained for 140-d-old breeders. The age of females reduced the hatchability, increased the late mortality in incubated eggs, and had no effect on fertility, total embryo mortality or eggshell structure, when analyzed by electron microscopy. The number of sperm trapped in the outer perivitelline layer (sptz/mm²) was determined in 10 fertile eggs per experimental unit. Young females fertilized by young males (80 days) had reduced sptz/mm². Progeny live performance was not affected by breeder's age. Breeders with 270 days retain fertility; however, their egg production, weight and hatchability of fertilized eggs is reduced. In conclusion, European quail breeders with 140 days of age have better egg quality, hatching and breeding results.

Egg- and meat-type quails were reared in groups of different sizes with a fixed female-to-male ratio of 2 to 1 and an area of 158 cm² per bird. The aim was to investigate the influence of group size on quail production and reproductive variables. To this end, 360 quails (180 meat and 180 egg-type quails) were assigned in a completely randomized experimental design to one of three treatments with ten replicates each. The treatments consisted of groups with nine, six, or three quails per cage. Birds were observed for three cycles of 14 days. Daily feed intake and feed conversion ratio were influenced (p < 0.05) by group size in both types of quails. Quail type influenced (p < 0.05) daily feed intake, feed conversion, and egg weight due to the typical differences between meat and egg-type birds. Despite the observed differences in production parameters, the mean values observed were typical of meat- and egg-type quails. The number of hydrolysis points (holes) per mm² on the vitelline membrane on the germinal disc area was higher in meat quails (2.89 ± 0.21) than in egg quails (2.15 ± 0.13). This parameter was not influenced by the number of birds per cage, which suggests that the number of males inside the cage did not modify the spermatozoa pool inside the female oviduct. We concluded that a ratio of two females per male in cages with three, six, and nine birds/cage is recommended, as no deleterious effect on quail reproduction was observed.