Lipid stability of egg and laying performance of Japanese quail feed with extract of guava (Psidium guajava L.).

Two experiments were conducted in order to evaluate the effect of dietary inclusion of guava extract on laying performance and lipid stability of egg of Japanese quails. For the first experiment, 384 Japanese quails with 42 days old were distributed in a completely randomized design with four treatments (0.0; 3.0; 6.0; 9.0 g.kg-1 guava extract), 6 replicates, and 16 birds/replicate. The experimental period lasted 84 days, divided into 4 cycles of 21 days. The parameters evaluated were: feed consumption, egg production, egg mass, feed conversion ratio, egg weight, and egg internal and external qualities. On the second experiment, 400 eggs from Japanese quails fed with diets containing four levels of guava extract were distributed in a completely randomized design with a 4x4 factorial arrangement (guava extract levels and storage time: 0, 9, 18, 27 days) with 5 replicates. Analysis of thiobarbituric acid reactive substances was performed on egg yolks. Data were submitted to regression analysis, using α=0.05. On the first experiment, the laying performance parameters were not influenced by the inclusion of guava extract in the feed, and eggshell thickness decreased linearly. On the second experiment an interaction was observed between the studied factors, affecting lipid oxidation in egg yolks. At nine days of storage, there was a quadratic effect of levels of dietary guava extract on lipid oxidation of yolk, being observed that using 4.8 g.kg-1 of guava extract on feed results in less lipid oxidation.

Effect of glycosaminoglycans on the structure and composition of articular cartilage and bone of broilers.

This study aimed to assess the influence of glycosaminoglycan (chondroitin and glucosamine sulfates) supplementation in the diet of broilers on the expression of matrix metallopeptidase 9 (MMP-9) and metallopeptidase inhibitor 2 (TIMP-2) genes, the synthesis of proteoglycans, collagen type II and chondrocytes, bone and cartilage macroscopy, bone mineral densitometry, bone breaking strength and mineral profile. A completely randomized design was carried out in a 3 × 3 factorial scheme (3 levels of chondroitin sulfate: 0.00, 0.05, and 0.10%; and 3 levels of glucosamine sulfate: 0.00, 0.15, and 0.30%), totaling 9 treatments. At 21 and 42 d of age, broilers were slaughtered, and tibias and femurs were collected for evaluation. There was an interaction (P < 0.05) of sulfates for the expression of MMP-9 and its inhibitor TIMP-2 in femur articular cartilage, as well as for the number of chondrocytes, collagen type II and proteoglycans in tibia articular cartilage, bone and cartilage macroscopy and mineral profile (P < 0.05), with better results obtained with the inclusion of chondroitin and/or glucosamine sulfates in the feed. In conclusion, chondroitin and glucosamine sulfates can be used in broiler diets in order to favor the development of the structure of the locomotor system (bones and joints), thus preventing locomotion problems.

Results of hatching and rearing broiler chickens in different incubation systems.

Hatchery efficiency is based on hatchability and the number of salable chicks. The hatchery sector has been seeking new alternatives to optimize production rates, including the use of different systems (multistage [MS] or single-stage [SS] machines) to improve incubation conditions. The present study aimed to compare results for hatchability, chick quality, and broiler performance of chicks from 2 incubator systems-MS and SS. The experimental design for hatchability, hatch window, egg weight loss, and chick performance variables was completely randomized with 2 treatments (MS and SS). Performance variables were analyzed as a 2 x 2 factorial arrangement (incubator type x chick sex). Egg weight loss between incubation and transfer was higher for eggs incubated in MS (P < 0.05). Hatchability was higher for eggs incubated in SS (P < 0.05), and chicks in SS had a longer hatch window (P < 0.05). Embryo diagnosis revealed higher final mortality for embryos incubated in MS (P < 0.05), as well as higher percentages of alive and dead pipped and cracked eggs (P < 0.05). Physical quality was better for chicks from SS (P < 0.05). There was no interaction between the studied factors for performance results (P > 0.05). Incubator type did not affect broiler performance for any of the studied ages (P > 0.05), whereas male broilers had better performance than females (P < 0.05). The SS incubation system proved better than the MS system at meeting embryo requirements during embryo development, with better hatching rates and chick quality, although performance variables were not influenced by incubation type.

Effect of a commercial product containing canthaxanthin for in ovo feeding to broiler embryos on hatchability, chick quality, oxidation status, and performance.

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.

Effects of breeder age on embryonic development, hatching results, chick quality, and growing performance of the slow-growing genotype.

The present study aimed to ascertain the effects of slow-growing breeder age on embryo development, incubation results, and chick quality and of the interaction between breeder age and hatching time on initial performance. A total of 630 hatching eggs obtained from a commercial flock of slow-growing broiler breeders (Isa Label Naked Neck) were evaluated in 2 experiments. The first experiment evaluated embryo development and hatching results for broiler breeder age treatments of 38 and 51 wk, whereas the second experiment evaluated broiler chick performance. For the second experiment, chicks were distributed in a 2 x 2 factorial randomized block (sex) experimental design consisting of 2 breeder ages (31 or 58 wk) and 2 hatching times (479-485 and 491-497 h). At 18 d of embryonic development, embryos of 51-wk-old breeders were larger than those of 38-wk-old breeders (P < 0.05), whereas yolk-free chick weight was similar (P > 0.05). Embryo organ weight was similar for the 2 breeder ages (P > 0.05); however, there was greater development of intestinal villi for embryos of the 51-wk-old breeders. There were no differences between breeder ages in hatchability and chick quality score (P > 0.05). Yolk-free chick weight at pulling was greater (P < 0.05) for chicks from 51-wk-old breeders. Hatching time did not affect performance from 1 to 7 d (P > 0.05); however, chicks hatching at 491-497 h had better performance from 1 to 28 d than did chicks hatching at 479-485 h (P < 0.05). In conclusion, the age of slow-growing breeders affects embryo villi development and chick weight but does not improve incubation results or chick quality. Chicks hatching later (491-497 h) had better performance results than chicks hatching earlier (479-485 h).

Dietary supplementation with glycosaminoglycans reduces locomotor problems in broiler chickens.

This study aimed to assess the influence of glycosaminoglycan (chondroitin and glucosamine sulfates) supplementation in the diet on the performance and incidence of locomotor problems in broiler chickens. A completely randomized design was carried out in a 3 × 3 factorial scheme (3 levels of chondroitin sulfate -0, 0.05, and 0.10%; and 3 levels of glucosamine sulfate -0, 0.15, and 0.30%). Each treatment was composed of 6 replications of 30 broilers each. The performance of broilers (average weight, weight gain, feed intake, feed conversion, and productive viability) was assessed at 7, 21, 35, and 42 d of age, whereas the gait score, valgus and varus deviations, femoral degeneration, and tibial dyschondroplasia were assessed at 21 and 42 d of age. Increasing levels of glucosamine sulfate inclusion linearly increased the weight gain from 1 to 35 and from 1 to 42 d of age of broilers (P = 0.047 and P = 0.039, respectively), frequency of broilers with no femoral degeneration in the right and left femurs, and the proliferating cartilage area of proximal epiphysis at 42 d of age (P = 0.014, P < 0.0001, and P = 0.028, respectively). The increasing inclusion of chondroitin and glucosamine sulfates led to an increase in the frequency of broilers on the gait score scale 0 (P = 0.007 and P = 0.0001, respectively) and frequency of broilers with no valgus and varus deviations (P = 0.014 and P = 0.0002, respectively) also at 42 d of age. Thus, chondroitin and glucosamine sulfates can be used in the diet of broiler chickens to reduce their locomotor problems.

Effect of vitamin E in ovo feeding to broiler embryos on hatchability, chick quality, oxidative state, and performance.

The objective of the present study was to ascertain the effect of in ovo feeding of vitamin E (VE) on the incubation results, quality, and oxidative state of newborn chicks and on the initial performance results. The design consisted of randomized blocks with treatments at different levels of VE (0.0, 27.5, 38.5, 49.5, and 60.4 IU). On 17.5 d of embryonic development, 780 eggs underwent in ovo injection using a manual needle. VE supplementation of 60.4 IU provided the highest hatching rate (P < 0.05) and shortest hatch window (P < 0.05). Better results regarding chick physical quality were observed in groups supplemented with VE (body weight, length, newborn chick quality score) and higher chick weight/egg weight ratios (P < 0.05). VE inoculation did not have any effect on the chicks' immunological system (P > 0.05). Greater development of the small intestine (intestine weight/yolk free chick weight and higher villi in duodenum) and better feed conversion over all periods studied (1 to 7, 1 to 14, and 1 to 21 d) were observed among chicks that received in ovo VE supplementation (P < 0.05). The total protein concentrations in the liver and striated breast skeletal muscle tissue were highest in chicks that received 60.4 IU of VE (P < 0.05). The highest catalase activity was observed in the livers of newborn chicks supplemented with 60.4 IU of VE (P < 0.05). It was concluded that in ovo VE supplementation improved the chicks' oxidative state, which led to improvements in incubation results, chick quality and performance results.