ABSTRACT. Two experiments were carried out to evaluate the effects of protease addition to the diet of broilers at a higher level (1× or 2×) than the nutritional value proposed for the enzyme. The first experiment, 1280 day-old chicks (Cobb500®) were randomly allocated (randomized block design, 2×2+1 factorial arrangement), five treatments, eight replicates containing 32 birds/replicate. Treatments consisted: control diet without protease (CD); CD + 1× nutritional value of the enzyme (CDM1); CD + 2× nutritional value of the enzyme (CDM2); CDM1 + protease; and CDM2 + protease. The experimental period was 42 days. The mean weight (AFW), feed intake (FI), weight gain (WG), feed conversion, and carcass yield were evaluated. Significant differences were observed for AFW, WG, FI, abdominal fat yield, and feet percentage in the carcass. In the second experiment, 120 Cobb500® chicks at 14 days of age were allotted in a completely randomized design, 2×2+1 factorial arrangement, five treatments, six replicates with four birds/replicate. The treatments were consistent with the first experiment. Significant improvements in the nitrogen balance were observed for the broilers that received protease. The use of the enzyme tested is recommended with the recommended nutritional matrix, improving the zootechnical indices of broilers.

RESUMO: A qualidade da casca está diretamente ligada à boa aceitabilidade do produto pelos consumidores, enquanto a indústria se preocupa com as perdas econômicas. Períodos prolongados de postura, doenças, nutrição, idade da ave e genética podem influenciar a qualidade dos ovos. Objetivou-se avaliar a influência do ambiente, idade da ave e período de armazenamento nas características físicas da casca de ovos de poedeiras comerciais. Foram utilizados 288 ovos de poedeiras Hy-line, distribuídos em um delineamento inteiramente casualizado em fatorial triplo 3x2x4, sendo os fatores: três idades (31, 62 e 88 semanas), temperatura de armazenamento (ambiente e refrigerado), e quatro períodos de armazenamento (um, 10, 20 e 30 dias), totalizando 24 tratamentos, com quatro repetições de três ovos. Avaliou-se a resistência, percentual e espessura da casca. Foram observadas diferenças, uma vez que os ovos armazenados em temperatura ambiente apresentaram diminuição na resistência de casca. Ovos de poedeiras em idade avançada (88 semanas) apresentaram pior resistência de casca em relação às demais idades, enquanto ovos provenientes de poedeiras jovens (31 semanas) apresentaram maior espessura de casca. A idade avançada da poedeira reduziu a qualidade de casca dos ovos, independentemente do ambiente de armazenamento. Ainda, os ovos armazenados em geladeira apresentaram melhor qualidade e integridade da casca em comparação com os armazenados ao ambiente.

ABSTRACT: Eggshell quality is directly linked to the good acceptability of the product by consumers, whereas the industry is concerned with economic losses. Prolonged periods of laying, diseases, nutrition, bird age and genetics can influence egg quality. This study aimed to examine the influence of the environment, bird age and storage period on the physical characteristics of the shell of eggs from commercial laying hens. The experiment involved 288 eggs from Hy-line hens, which were distributed in a completely randomized design with a triple 3×2×4 factorial arrangement represented by three ages (31, 62 or 88 weeks), two storage temperatures (ambient or refrigerated), and four storage periods (one, 10, 20 or 30 days), totaling 24 treatments. Four replications were used with three eggs each. Eggshell strength, percentage and thickness were measured. Differences were observed, with the eggs stored at room temperature exhibiting lower shell strength. Laying eggs at an advanced age (88 weeks) resulted in decreased eggshell strength as compared with the other ages, whereas the eggs from young layers (31 weeks) had a thicker shell. The advancing age of the laying hens reduced eggshell quality, regardless of the storage environment. Nonetheless, the eggs stored in the refrigerator showed better eggshell quality and integrity than those stored at ambient temperature.

ABSTRACT The objective of this study was to evaluate the effects of guava extract standardized in phenolic compounds (SGE) on broiler performance, nutrient digestibility, and intestinal histomorphometry. A total of 300 one-day-old male Cobb-500® broiler chicks were distributed in a completely randomized design with five treatments (basal diet supplemented with 120 mg vitamin E/kg and basal diet supplemented with 0, 600, 800, or 1,000 mg SGE/kg) and six replicates of ten birds each. Performance was evaluated at seven and 21 days of age; digestibility of nutrients was determined by total excreta collection from 18 to 21 days of age; and histomorphometry of the small intestine was assessed at 21 days of age. Broilers fed diets supplemented with SGE or vitamin E had higher body weight and weight gain and better feed conversion than those fed unsupplemented diet at seven days of age. At the same age, there was a quadratic effect of SGE levels on body weight and weight gain, with better weights for 715 and 716 mg SGE/kg, respectively; and a decreasing linear effect for feed conversion. At 21 days of age, body weight and weight gain increased linearly with the inclusion of SGE in diet. Digestibility of feed nutrients was not influenced by treatments. Broilers fed diet supplemented with 800 or 1,000 mg SGE/kg had greater villus height and villus:crypt ratio of the duodenum than those fed unsupplemented diet. Villus height in the jejunum of broilers fed diet supplemented with 600 mg SGE/kg was lower than that of broilers that received vitamin E. Guava extract standardized in phenolic compounds can be used in diets for broilers in the starter phase, considering that the extract increases weight gain, reduces feed conversion, and helps in the development of the intestinal mucosa.

ABSTRACT. The main purpose of this study was to evaluate the characteristics of eggs produced by Japanese quails fed with guava extract. A total of 400 eggs collected from the quails fed with experimental diets, were distributed in a completely randomized design in factorial arrangement 4 x 4 with main effects including four dietary levels of guava extract (0, 3, 6 and 9 g kg-1) and four storage periods (0, 9, 18 and 27 days) totalizing 16 treatments with five replicates of five eggs. The eggs were produced by Japanese quails, fed with experimental diets. The diets were isonutritive formulated by corn-soybean basis. The eggs were stored for different periods, at the same conditions, to constitute the treatments. The parameters evaluated were egg weight loss (g and %), yolk color, Haugh unit, specific gravity, eggshell thickness and pH of the yolk and albumen. Data were submitted to ANOVA, and means were compared using Scott-Knott test, using α = 0.05. The specific gravity of fresh eggs was better with the use of 6 g kg-1 of guava extract in the diet. The use of 3 g kg-1 of guava extract resulted in smaller eggshell thickness of fresh eggs. The Haugh unit was affected just by the storage periods. The dietary guava extract (3, 6 or 9 g kg-1) increased the pH of albumen in eggs stored for 27 days. The use of 6 g kg-1 of guava extract in quails diet increase the specific gravity in fresh eggs and increase the yolk color when the eggs are stored.

Resumo Realizou-se um experimento objetivando avaliar a utilização de Neem como antimicrobiano em rações de frangos de corte. Foram utilizados 240 pintos de corte, Cobb, com 1 dia de idade, distribuídos em delineamento inteiramente casualizado, 4 tratamentos, 6 repetições, 10 aves por unidade experimental, o período experimental foi de 21 dias. Os tratamentos consistiram: dieta basal sem inclusão de antimicrobiano; dieta com 0,05% de tilosina; dieta com 0,05% e 0,1% de Neem. Avaliou-se: o desempenho zootécnico, a digestibilidade da ração, contagem intestinal de Salmonella sp. e Escherichia coli, e o desenvolvimento dos órgãos linfoides. Dados de desempenho e metabolização dos nutrientes da ração foram submetidos à ANOVA, médias comparadas pelo teste Tukey, adotou-se α=0,05. Dados de contagem de E. coli foram analisados pelo teste de Kruskal-Wallis. O Neem não influenciou as variáveis de desempenho. O coeficiente de metabolizabilidade da matéria seca e extrato etéreo da ração foi melhor com utilização de tilosina (P<0,05). Não se observou crescimento de Salmonella durante o período experimental. A utilização de Neem não reduziu a população de E. coli, e não influenciou no peso dos órgãos linfoides. A utilização do Neem não afetou o desempenho, digestibilidade e microbiota intestinal das aves até 21 dias.

Abstract In the present work, we carried out an experiment aiming at evaluating the use of Neem as an antimicrobial substance in the feeds of broiler chickens. We used 240 one-day-old Cobb broiler chicks distributed in an entirely casual design, with 4 treatments, 6 repetitions and 10 birds per experimental unit, during a 21-day experimental period. Treatments consisted of a basal diet with no antimicrobial inclusion, a diet with 0.05% of tylosin, and a diet with 0.05% and 0.1% of Neem. Parameters evaluated were zootechnical performance, feed digestibility, intestinal count of Salmonella sp. and Escherichia coli, and the development of lymphoid organs. Data on the performance and metabolization of nutrients were subjected to an ANOVA and averages were compared with a post-hoc Tukey test considering α=0.05. Data on E. coli counts were analyzed with a Kruskal-Wallis test. Neem did not influence performance variables. The metabolization coefficient of dry matter and feed ethereal extract was better with tylosin (P<0.05). No growth of Salmonella was observed during the experiment. The use of Neem did not reduce E. coli population and had no influence on lymphoid organs' weight. Therefore, Neem had no effect on the performance, digestibility and intestinal microbiota of birds up to 21 days old.