The objective of this study was to evaluate whether probiotic supplementation to laying hens can improve the quality of eggs during storage. The trial was developed in a commercial farm, in which light-weight laying hens (36 weeks old) housed in cages were randomly selected for one of two different treatments: a control group fed non-supplemented diets, or birds fed with diets supplemented with 50 g/ton of probiotics. The trial lasted for 84 days, comprising three productive phases of 28 days each. The fresh egg quality was evaluated and then the eggs were stored and randomly separated for quality assessment at each storage interval (7, 14, 21, 28, 35, and 42 days). Means were compared using variance analysis considering differences at 5 and 10%. The probiotic was able to improve albumen weight, yolk length, yolk height, and yolk index (p < 0.05) during storage. Yolk color (fan) was also improved by 3.9% (p < 0.001), while increases of 1.35% (p < 0.001) in luminosity, 8.05% (p < 0.001) in red intensity, and 3.4% (p < 0.001) in yellow intensity were observed in comparison to the control group. Probiotic treatment was able to reduce by 2.03% (p < 0.001) yolk pH, and by 19.65% (p < 0.05) TBARS levels when compared to the control treatment. Therefore, the addition of probiotics to laying hen diets is an effective strategy to improve egg quality during storage.

A trend toward animal welfare improvement is observed in animal production, in addition to restrictions imposed on the use of antimicrobials. This study's objective was to evaluate whether β-mannanase and probiotic supplementation can change hen's behavior. Light weight laying hens (36 weeks old) were housed in cages randomly allocated to one of four different treatments: control group, fed non-supplemented diets; diets supplemented with 300 g/ton of β-mannanase; diets supplemented with 50 g/ton of probiotic; or diets containing both 300 g/ton of β-mannanase and 50 g/ton of probiotic. The behavior of 24 birds was recorded for a week using video cameras. The frequency and time of main behaviors (eating, walking, standing, sitting, drinking, and exploring) were analyzed in three periods per day (from 09:00 to 09:15; from 01:00 to 01:15, and from 04:00 to 04:15), as well as the time of other behaviors (leg-stretching and wings, scratching, wing-flapping, aggressive and non-aggressive pecks). Frequency and lesion scores were also analyzed using a visual score of three body regions: neck, tail, and cloaca; as well as comb injuries. β-mannanase was able to increase the frequency of feeding behavior by 49% (P &lt; 0.05) and hens also spend 20% (P &lt; 0.05) more time in this behavior compared to the control treatment. The use of probiotics also enhanced by 39% (P &lt; 0.05) the frequency and 19% the time (P &lt; 0.05) and the supplementation with combined additives was able to increase by 29% (P &lt; 0.05) the frequency and 25% (P &lt; 0.05) the time in feeding behavior. β-mannanase and probiotics also increased the frequency and time spent exploring behavior (P &lt; 0.05) and promoted a higher frequency in standing behavior (P &lt; 0.05) and decreased the time spent on sitting behaviors (P &lt; 0.05). The combined additives showed less frequency and time in sitting behaviors (P &lt; 0.05), while increased wing-flapping behavior (P &lt; 0.05). All the treatments were able to reduce pecking (P &lt; 0.05). Therefore, the addition of β-mannanase and probiotics to laying hen diets is an effective strategy to improve bird welfare.

No abstract

A intensificação do sistema de produção avícola trouxe profundas mudanças no ambiente físico e social das aves domésticas. O manejo dessas aves tem recebido considerável atenção nos últimos anos devido às novas demandas por parte dos consumidores, principalmente aquelas relacionadas ao bem-estar. O comportamento é a maneira como os animais respondem aos diferentes estímulos que encontram em seu ambiente. As expressões comportamentais das aves domésticas e a aplicação desse conhecimento no cuidado dos animais desempenha um papel importante na maximização da eficiência de produção da cadeia avícola. Assim, definir limites éticos e diretrizes para a produção avícola é fundamental para fomentar o desenvolvimento de novas práticas produtivas, e assim garantir qualidade e produtividade sem colocar em risco o bem-estar dos animais. Esta revisão destacará as principais expressões comportamentais das aves domésticas, dentre elas as expressões sociais, alimentares, reprodutivas, além de estereotipias, e identificará as estratégias de adaptação social. Assim, promovera ao leitor e a comunidade científica uma melhor compreensão de assuntos pouco discutidos para assim auxiliar em análises comportamentais.