Biometric Characterization of the Portuguese Autochthonous Hens Breeds

Abstract

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.

Small Scale Egg Production: The Challenge of Portuguese Autochthonous Chicken Breeds

“…The main challenge in the traditional production system for Portuguese native hens presupposes product differentiation in the dual-purpose breeds, their potential improvement, an agroecologically based breed characterization, and commercial organization with a market-oriented vision. Functionally, from a productive point of view, in unselected populations, large animals tend to be destined for meat production and small animals for egg production [41,48]; however, in our results, the Preta Lusitânica genotype, the smallest (shorter, lighter) hen [32], was shown to be the least productive. Considered genetically closer to the ancestor of avian populations [31], its use in cultural and religious practices, and the absence of a selection program could explain its low laying breed capacity.…”

“…Genetic and productive characterization of the Portuguese autochthonous breeds is relatively recent [31,32,[34][35][36][37], and there is still minimal information about small-scale production, demographic evolution, small producers' social impact and commercial circuit organization.…”

“…Since 2003, conservation programs for local chicken breeds have been developed in cooperation with the breeders' association (AMIBA), a genealogic register was created, and breed standards were approved. Recent studies of Portuguese chicken breeds have mainly focused on phenotypic and productive characteristics, defining patterns and productive systems [22,31,32].…”

Discriminant Canonical Tool for Differential Biometric Characterization of Multivariety Endangered Hen Breeds

“…Biometric studies have been performed worldwide to make breed characterization feasible and to be considered during the implementation of conservation strategies and policies [ 16 ]. This suggests that the preservation of the breed diversity may be one of the motor elements ensuring the future survival of a breed.…”

“…For local producers to be able to fulfill market demands, products and the elements needed to ensure their constant supply must be defined through breed characterization zoometrically, genetically, or even productively. Contextually, the characterization of local populations, as well as the relationship among already established breeds, can provide pieces of evidence on the mechanism and events that contributed to the origin and development of native poultry breeds in the south region of Spain, as well as the adaptive mechanisms that may have permitted their survival in time [ 16 ]. Additionally, breed standardization could be an important tool for the evaluation of birds within their flocks and determine certain measurements for the selection of the best animals [ 17 ].…”