Mitochondrial DNA diversity was analysed in 19 Iberian and six foreign sheep breeds. Three mtDNA lineages (B, A and C) were found in the Iberian sheep, with type B clearly predominating over the others. The results were analysed for each of the morphologically determined breed groups in Iberian sheep: Merino, Entrefino, Churro and Iberian trunks. MtDNA lineage C was found only in the Iberian trunk composed of Montesina and Ojalada. These two populations had high mtDNA variability, and in the Iberian sheep only Merino Branco had more variation. The other three Merino types studied showed moderate variability, including the most authentic Merino, the Spanish Merino. These three Merinos clustered closely in a multidimensional scaling representation of distances, while the fourth breed (Merino Branco) showed a clear separation. As for the other two trunks, breeds from the Churro group showed greater maternal uniformity while results for populations included in the so-called Entrefino trunk seemed to have a more heterogeneous maternal origin. The results obtained are discussed with available data from nuclear markers and with morphological classifications, and all this information is analysed in relation to the origin of the different Iberian sheep breeds.

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.

The “Branca” breed is a dual-purpose Portuguese autochthonous chicken breed, produced in extensive systems and in small flocks, especially in the Entre Douro and Minho regions. A total of 40 birds (n = 20/sex) were slaughtered between 38 and 42 weeks (males) and 110 and 120 weeks (females), and carcass and meat quality parameters were evaluated. The results showed significantly higher weights and differences for males between sexes and pieces (p ≤ 0.05) in the meat physicochemical composition. Water holding capacity (WRC), moisture and ash contents were influenced by sex. They were higher in males in the breast and drumstick and lightness (L*) and lipid content were higher in females (p ≤ 0.05). The breast meat presented greater lightness, moisture, ash and protein contents, while the drumstick showed a higher pH value, redness (a*) and lipid content, in both sexes (p ≤ 0.05). Regarding the nutritional properties, “Branca” meat revealed a good proportion of minerals and the female meat showed, in both pieces (p ≤ 0.05), significantly lower values for total saturated fatty acids (SFAs) and higher values for monounsaturated fatty acids (MUFAs). Breast meat was richer in n-3-PUFAs (C22:5n-3 and C22:6n-3) in both sexes (p ≤ 0.05). Considering the results obtained, it can be concluded that “Branca” breed meat is a healthy food characterized by a good general nutritional profile.

Background/Objectives: Animals destined for human consumption play a key role in potentially transmitting bacteria carrying antibiotic resistance genes. However, there is limited knowledge about the carriage of antibiotic-resistant bacteria in native breeds. We aimed to characterize the phenotypic profiles and antibiotic resistance genes in Escherichia coli isolated from bovines, including three native Portuguese bovine breeds. Methods: Forty-nine E. coli isolates were selected from 640 fecal samples pooled by age group (eight adult or eight calf samples) from each farm, representing both dairy cattle raised in intensive systems and meat cattle raised in extensive systems in Northern Portugal. The presumptive E. coli colonies plated onto MacConkey agar were confirmed using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). The antibiotic resistance profiles were screened by antimicrobial susceptibility testing (EUCAST/CLSI guidelines), and the antibiotic resistance genes by PCR. Results: Most isolates showed resistance to ampicillin (69%), tetracycline (57%), gentamicin (55%), and trimethoprim + sulfamethoxazole (53%), with no resistance to imipenem. Resistance to at least one antibiotic was found in 92% of isolates, while 59% exhibited multidrug resistance. Most calf isolates, including those from native breeds, showed a multidrug-resistant phenotype. Among the adults, this was only observed in Holstein-Friesian and Barrosã cattle. None of the Holstein-Friesian isolates were susceptible to all the tested antibiotics. ESBL-producing E. coli was identified in 39% of isolates, including those from Holstein-Friesian calves and adults, Cachena calves and Minhota adults. The sul2 gene was detected in 69% of isolates, followed by bla_CTX-M (45%), aac(3′)-IV (41%), and aac(6′)-Ib-cr (31%), with a higher prevalence in adults. Conclusions: This pioneering study highlights the concerning presence of multidrug-resistant E. coli in native Portuguese cattle breeds.

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.