The objective of the study was twofold: (i) to review the genetics of production and resilience traits of indigenous Greek small ruminant breeds as well as the evolution of national breeding programs, and (ii) explore innovative and feasible approaches to overcome the challenges and constraints towards improving these breeds and enhancing the sustainability of the small ruminant sector. Previous studies on the genetic basis of production and resilience traits of indigenous breeds revealed high improvement potential. However, the lack of follow-up action has failed to produce applicable results. Thus, implementation of scientific findings in existing breeding programs for these breeds is extremely limited. The latter has contributed to the overall poor success of such programs. Furthermore, due to the fact that most farmers do not comprehend the strategic importance of genetic improvement and lack motivation for self-funding, breeding programs have mostly relied on European or government funding; the latter has resulted in intermittent implementation. Therefore, most programs failed to improve performance of indigenous Greek breeds, many of which were consequently replaced by foreign breeds of higher productivity and documented merit. In order to facilitate the design of breeding schemes and overcome the challenges towards improvement of indigenous breeds, an integrative approach is necessary. The latter should be based on identification of specific breeding objectives, reflecting the priorities and needs of the sector, as well as the capacity of the indigenous populations. Scientific advances exemplified by genomic selection and novel reproductive technologies will enable faster and more effective genetic improvement. The overall approach is expected to enhance the competitiveness of indigenous Greek small ruminant breeds and the sustainability of the sector.

Cattle breeds or crossbreds with high productivity traits have been developed to meet a growing demand for food. When intensive farming practices are followed, animals face several challenges which can result in poor performance, compromised welfare and the reduced quality of their products. Our study aims to highlight the resting values of the physiological oxidative stress that three cattle breeds exhibit, and their potential relationship with meat quality. For this purpose, we determined the levels of five common redox biomarkers (glutathione (GSH), catalase (CAT), total antioxidant capacity (TAC), thiobarbituric reactive substances (TBARS) and protein carbonyls (CARBS)) in the tissues of three commonly used beef cattle breeds (Charolais (CHA), Limousin (LIM) and Simmental (SIM)) and their association with specific meat quality traits that depend on color, pH and texture. The results revealed that LIM cattle breed animals have elevated intrinsic antioxidant defense systems in comparison to CHA and SIM cattle breed animals. In addition, the meat quality parameters were associated with the redox biomarkers. We propose that the determination of specific antioxidant parameters in the blood might be used as potential biomarkers to predict meat quality. This would allow farmers to nutritionally intervene to improve the quality of their products.

Genetic selection for higher productivity increased dairy sheep susceptibility to diseases and environmental stressors, challenging their health and welfare status and production efficiency. Improving resilience to such stressors can enhance their ability to face these challenges without compromising productivity. Our objective was to estimate genomic heritability and perform genome-wide association studies (GWAS) to detect SNPs and candidate genes associated with three proxy traits for resilience (milk somatic cell count—SCC, lactation persistency—LP, body condition score—BCS) of Chios and Frizarta dairy ewes. We used genome-wide genotypes of 317 Chios and 346 Frizarta ewes. Individual records of milk yield and BCS, and milk samples were collected monthly for two consecutive milking periods; samples were analyzed to determine SCC. The LP was calculated as the regression coefficient of daily milk yield on days from lambing. Within breed, variance components analyses and GWAS were performed using genomic relatedness matrices in single-trait animal linear mixed models. Genomic-based heritability estimates were relatively high (BCS: h² = 0.54 and 0.55, SCC: h² = 0.25 and 0.38, LP: h² = 0.43 and 0.45, for Chios and Frizarta ewes, respectively), compared to previous pedigree-based studies. The GWAS revealed 7 novel SNPs associated with the studied traits; one genome-wide and two suggestive significant SNPs for SCC (Frizarta: rs403061409, rs424064526 and rs428540973, on chromosomes 9, 1 and 12, respectively), one suggestive significant SNP for BCS (Chios: rs424834097 on chromosome 4) and three suggestive significant SNPs for LP (Frizarta: rs193632931 and rs412648955 on chromosomes 1 and 6, Chios: rs428128299 on chromosome 3). Nineteen candidate genes were detected: two for BCS (Chios: POT1, TMEM229A), thirteen for SCC (Frizarta: NTAQ1, ZHX1, ZHX2, LOC101109545, HAS2, DERL1, FAM83A, ATAD2, RBP7, FSTL1, CD80, HCLS1, GSK3B) and four for LP (Frizarta: GRID2, FAIM, CEP70—Chios: GRIP1). Present results show that resilience in the studied dairy sheep breeds is heritable and advance existing knowledge on the genomic background of SCC, LP, and BCS. Future research will quantify effects of different alleles of significant SNPs on the studied traits and search for possible correlations among traits to facilitate their effective incorporation in breeding programs aiming to improve resilience.

The objective of this study was to assess the impact of breed and slaughter hygiene practices on beef quality traits in Northern Greece. A random sample of 159 beef carcasses from three breeds, Aberdeen Angus (AA, n = 38), Holstein (HO, n = 42), and Limousin (LI, n = 40), and crossbred (CR, n = 39) males were used. The chroma, pH, texture, chemical composition, and fatty acid profile were assessed using the Longissimus dorsi muscle. The muscle histomorphometry was assessed using the psoas major samples. Microbiological analyses were conducted on the beef carcasses to evaluate slaughter hygiene. A comparative analysis using ANOVA, Mann–Whitney, and Kruskal–Wallis tests was performed to assess the effects of breed and slaughter hygiene on the meat quality traits. The meat quality differed significantly (p < 0.05) between the breeds. Specifically, the LI beef exhibited higher lightness (L*) values compared to those of the AA and HO beef. The CR breed produced the reddest beef, which differed significantly from the AA and HO beef. The beef yellowness (b*) was higher in the AA breed compared to the other breeds. The AA and CR beef was more tender than the LI beef. The AA beef exhibited the lowest protein and highest fat content, while the LI beef was the leanest. The monounsaturated fatty acid (MUFA) concentrations in the AA beef were 22% higher than those in the HO beef, whereas the HO beef had 23% higher levels of saturated fatty acids (SFAs). The total mesophilic viable counts among the slaughterhouses exceeded the lower acceptable threshold (3.5 log CFU/cm²), indicating inadequate slaughter hygiene practices that could impact beef quality and safety. Globally, this is the first comprehensive study that uniquely combines techniques for assessing beef quality from whole carcasses to individual muscle fibers.

In recent years, a rising interest has been directed towards the use of nutraceuticals in the zootechnical sector, including probiotics, prebiotics, and synbiotics, as a way to support production efficiency and cope with the increasing limitations to the use of antibiotics. In poultry, however, most studies on these products have been conducted on broilers, while less information is available on their benefits to other productive categories. The present field study aimed to assess the effects of a multi-species synbiotic product (PoultryStar® sol) on the gut health and productive performance of broiler breeders. A total of 24761 day-old Ross 308 parent stock chicks were acquired from a single hatchery and placed on the same farm. Female chicks were divided into three groups and raised in different houses (A, B, and C), in which males were introduced at the age of mating and followed until 40 weeks of age. The synbiotic was provided by drinking water to the flocks in houses A and B, while house C was kept as control. Following the manufacturer’s guidelines, the product was administered intermittently once every two weeks, except in the first and the twenty-first week when it was supplied for three consecutive days. Data on performance parameters, egg quality traits, bacterial enteritis scoring, intestinal morphometry, and histopathology were recorded, and the caecal content was collected at 15, 25, and 40 weeks of age to investigate the intestinal microbiota using high-throughput next-generation sequencing. Synbiotic-treated hens showed significantly higher survivability during production compared to the control group. No clear differences were observed between treated and control chickens in terms of egg production and quality, and the effect of the synbiotic on weight gain also appeared limited. From 25 weeks onwards, synbiotic-treated chickens scored better in terms of macroscopical lesions and had longer intestinal villi. Significant differences in crypt length and histopathological lesions were also found at multiple sampling points. A treatment effect on caecal bacterial composition was detected with a differential abundance of Gastranaerophilales, Lachnospiraceae, Helicobacter, Ruminococcaceae, and Clostridia, among others. Taken together, obtained results support the beneficial effects of the intermittent administration of the synbiotic product PoultryStar® sol on the gut health of broiler breeders. Keywords: Broiler breeder, Gastrointestinal health, Histopathology, Microbiota, Synbiotic

Sheep farming in Greece is focused on milk production. Meat is considered a by-product and consists mainly light carcasses of undefined quality. The main challenge of the sector is to ensure sustainability, and hence efforts are towards efficient use of available resources, including undervalued carcasses of local fat-tailed sheep. The objective here was twofold: (i) to assess the carcass quality of fat-tailed sheep slaughtered at different live weights and (ii) to compare them with carcasses from thin-tailed sheep. In total, 146 fat-tailed and 97 thin-tailed dairy sheep were used. They belonged to five live-weight categories (LWC), representing 25%, 35%, 50%, 70% and 100% of mature body weight. Carcass length/weight/yield/pH and wither height were recorded. Muscle fiber minimum Feret’s diameter and meat color/tenderness/moisture/lipid and protein content were determined. Sex and LWC differences in fat-tailed sheep were assessed. Parametric and non-parametric tests were used to compare with thin-tailed sheep, considering the effects of LWC, sex and their interactions with sheep population (fat-tailed/thin-tailed). Most traits were significantly different (p < 0.05) between groups of fat-tailed sheep. Carcass yield of fat-tailed sheep was significantly higher compared to thin-tailed (p < 0.01). Interactions of sheep population with LWC or sex affected wither height, carcass pH, meat color and tenderness (p < 0.05). Fat-tailed sheep meat quality is equal or higher compared to thin-tailed. Finishing weights corresponding to 50 and 70% LWC may improve capitalization of fat-tailed carcasses.