Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time, and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space. While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes, vast areas of the tropics remain understudied. In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity, but it remains among the least known forests in America and is often underrepresented in biodiversity databases. To worsen this situation, human-induced modifications may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge, it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Metabolism of broilers subjected to different lairage times at the abattoir and its relationship with broiler meat quality

ABSTRACT An investigation was made into the effects of different lairage times and the position of chicken crates during transport to the slaughterhouse on the biochemical and hematological profile and physical parameters of broilers, such as color and pH of their breast meat. The treatments were defined by the animals slaughtered after 0, 2, 4 and 6 hours of lairage time at the slaughterhouse, transported in crates located in the top and bottom layers of the truck. It was found that increasing the lairage time at the slaughterhouse to over two hours reduced the number of lymphocytes and increased the heterophil/lymphocyte (H/L) ratio and the basophil count in the hemogram. In addition, lactate dehydrogenase (LDH) activity and cholesterol levels increased and plasma triglyceride and glucose levels decreased. The position of the crates in the truck altered the creatine kinase (CK) activity, and the highest enzyme activity was found in birds transported in the top layer of crates in the truck. Furthermore, the long lairage time in the slaughterhouse increased the pH and the value of a* (redness value) and decreased the lightness value of breast fillets. The interaction significant between 4 and 6 hours of lairage time and the position of the crate in the top layer of the truck favored the development of dark, firm, dry (DFD) meat

Exigência nutricional de lisina digestível para galinhas poedeiras no período de 34 a 50 semanas de idade Nutritional requirement of lysine for laying hens in the period from 34 to 50 weeks old

Com o objetivo de estabelecer a exigência nutricional em lisina para galinhas poedeiras leves e semipesadas, no período de 34 a 50 semanas de idade, 360 poedeiras (metade Lohmann e metade poedeiras Lohmann Brown) foram submetidas à ração basal contendo 2.850 kcal EM/kg, 15,0% PB, suplementada com cinco níveis (0,00; 0,05; 0,10; 0,15 e 0,20%) de L-lisina, de modo a proporcionar 0,584; 0,634; 0,684; 0,734 e 0,784% de lisina digestível nas rações. Foi utilizado esquema fatorial 5 x 2 (nível de lisina e linhagem de aves), com seis repetições por tratamento e seis aves por unidade experimental, em um delineamento inteiramente casualizado. Foram avaliados a produção de ovos (%), a massa e o peso médio dos ovos (g), o consumo de ração (g/ave.dia), a conversão alimentar (kg ração/dúzia ovos), a mudança de peso corporal (g) e a qualidade interna dos ovos (unidade Haugh e índice de albúmen e gema). Os níveis de lisina não influenciaram a mudança de peso corporal, o consumo de ração e a qualidade interna dos ovos em ambas as linhagens. A conversão alimentar e a produção de ovos, o peso médio e a massa dos ovos foram influenciados positivamente pelos níveis de lisina, em poedeiras leves e semipesadas. A exigência em lisina digestível, estimada pelo modelo quadrático, para as aves leves e semipesadas, foi de 0,732 e 0,715% na ração, que corresponde ao consumo diário por ave de 893 e 804 mg lisina/ave.dia, respectivamente.<br>With the objective to establish the nutritional requirement of lysine for light and semi-heavy laying hens, in the period from 34 to 50 weeks old, 360 laying hens (half Lohmann and half Lohmann Brown) were submitted to a basal ration containing 2.850 kcal ME/kg, 15.0% CP, supplemented with five levels (0.00, 0.05, 0.10, 0.15 and 0.20%) of L-lysine, to provide 0.584, 0.634, 0.684, 0.734, and 0.784% of digestible lysine in the rations. A 5 x 2 (lysine level and laying hen strain) factorial arrangement, with six replications per treatment and six hens per experimental unit in a completely randomized design was used. Egg production (%), egg mass and average egg weight (g), feed intake (g/hen.day), feed conversion (kg feed /egg dozen), body weight change (g) and internal egg quality (Haugh unit, albumen and yolk index) were evaluated. The lysine levels did not affect the body weight change, feed intake and egg quality in both laying hen strains. Feed conversion and egg production, average egg weight and egg mass were positive influenced by the lysine level, in light and the semi-heavy. The digestible lysine requirement estimated by quadratic model, for the light and the semi-heavy laying hens, was 0.732 and 0.715% in the ration, corresponding to the daily intake per hen of 893 and 804 mg lysine/day, respectively