Promotion of the conservation and preservation of local breed’s biodiversity combined with the concept of sustainable agriculture and development of economically marginal areas are important policies to implement in modern society. The biometric characterization, contributing to maintain phenotypic traits, is a significant tool in breeding programs, which revaluate local breeds, allow the preservation of animal biodiversity and support consumer demands. This paper approaches the biometric characterization of the Portuguese poultry breeds through the study of sexual dimorphism and breed differentiation using six zoometric measures as differentiation criteria. A total of 429 fowl (66 males and 426 females) were studied and the parameters recorded were body weight, body length, chest circumference, shank length, shank diameter and wingspan. A highly sexual dimorphism was evident, in all breeds, with the “Branca” breed being the most zoometrically distant. Concerning Principal Component Analysis, the highly correlations observed between body length, wingspan and shank length, determined the generalized animal form and could be used as selection criteria for improving body size. Breeding programs aiming to preserve these local genetic resources should consider the dual purpose of these breeds: sustainability and cultural legacy, and the offer to urban consumers a source of differentiated high-quality products.

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The objective was to estimate genetic correlations between body weight (BW), scrotal circumference and visual evaluation scores of body conformation measured at standard ages in Guzerat cattle. All measurements were performed at 205 (weaning age), 365, 450 and 550 days of age; for BW, two additional measurements (at birth and 120 days of age) were realized. The data utilized in this study were retrieved from a database of the Brazilian Association of Zebu Breeders that contained information of registered Guzerat animals born between 1970 and 2013. Genetic parameters were estimated in bi-trait analyses by using Bayesian inference. Genetic correlations between BW at 205 and 450 days of age with other traits were high and positive, whereas the correlations between visual evaluation scores with other traits were moderate. Based on correlations herein obtained, we conclude that selection based on BW results in increased visual scores and scrotal circumference, leading to improvements in productive performance and animals with best body conformation.

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Biodiversity concerns and the sustainability of agroecological systems, together with consumer demand for higher quality products from alternative and extensive farming methods, have reinforced interest in local breeds that are well adapted to low-input environments. The first reference to Portuguese poultry breeds appeared in the 1930s, with registration and breeding programs of native breeds only being implemented in the last ten years. Portuguese chicken breeds (Pedrês Portuguesa, Preta Lusitânica, Amarela, and Branca) are almost extinct and are currently bred on small-scale farms for egg and meat production. This study aimed to characterize the performance of laying hens, evaluating the influence of genotype, age, and season on egg production over four years in farm conditions. The results highlight the Pedrês Portuguesa as the most productive breed regarding egg production and reveal a tendency for an increase in egg production performance by the Branca in contrast with the lower productive capacity of the Preta Lusitânica. Older hens start laying earlier in consecutive laying periods, present a shorter peak, and an inferior number of total eggs/cycle. There is a need to establish breeding goals and to evaluate and revise breeding programs to increase productivity in autochthonous Portuguese chicken breeds.