Placental Characteristics Classification of Various Native Turkish Sheep Breeds

Foetal programming in sheep: Reproductive and productive implications

The aim of this study was to evaluate the effects of pregnant ewe nutrition on the performance of offspring in terms of meat, wool production, and reproduction. Foetal programming in sheep has focused on several aspects related to foetal growth, postnatal production, behaviour, and immunological performance. Currently, significant efforts are being made to understand the endocrine, metabolic, and epigenetic mechanisms involved in offspring development. Current studies have not only evaluated the foetal period, despite the pre-conception parental nutrition has demonstrated an effect on the foetal, embryonic, and pre-implantation periods and can generate permanent effects in the foetal and postnatal phases. The performance of offspring is the result of interactions between the genome, epigenome, and environmental interventions during conception. Several factors influence the expression of phenotypic characteristics in progenies; however, this study focused on presenting data on the effect of pregnant ewe nutrition alone on foetal growth and the productive aspects of their offspring.

The Effect of Birth Weight on Fattening Performance, Meat Quality, and Muscle Fibre Characteristics in Lambs of the Karayaka Native Breed

This investigation aimed to assess the influence of birth weight on post-weaning fattening performance, meat quality, muscle fibre characteristics, and carcass traits in Karayaka lambs. The study categorized the lambs into three distinct groups based on birth weight: low birth weight (LBW), medium birth weight (MBW), and high birth weight (HBW). Throughout the fattening phase, the lambs were given ad libitum access to food and water, culminating in the slaughter at the end of the study. Following slaughter, warm and cold carcasses were weighted, and specific muscles (longissimus thoracis et lumborum [LTL], semitendinosus [ST], and semimembranosus [SM]) were isolated for the evaluation of muscle weights, muscle fibre types (Type I, Type IIA, and Type IIB), and muscle fibre numbers. Carcass characteristics were also determined, including eye muscle (LTL) fat, loin thickness, and meat quality characteristics, such as pH, colour, texture, cooking loss, and water-holding capacity. The statistical analysis revealed highly significant differences among the experimental groups concerning muscle weights and warm and cold carcass weights (p < 0.01), with the lambs in the HBW group exhibiting a notably higher carcass yield (in females: 45.65 ± 1.34% and in males: 46.18 ± 0.77%) and LTL, ST, and SM (except for female lambs) muscle weights than the lambs in LBW group (p < 0.01). However, apart from the texture of LTL and ST muscles, no significant differences in meat quality parameters were observed among the treatment groups (p > 0.05). Notably, the birth weight of lambs did not impart a discernible effect on the total number and metabolic activity of muscle fibres in LTL, ST, and SM muscles. Nonetheless, a noteworthy distinction in the fibre area of Type I fibres in the LTL muscle of male lambs (LBW: 30.4 ± 8.9, MBW: 29.1 ± 7.3 and HBW; 77.3 ± 15.4) and in the ST muscle of female lambs (LBW: 44.1 ± 8.1, MBW: 38.8 ± 7.7 and HBW: 36.9 ± 7.1) were evident among the birth weight groups (p < 0.05). The study also found that the mean fat thickness values of eye muscles in Karayaka lambs, as obtained by ultrasonic tests, were below the typical range for sheep. In synthesis, the outcomes of this study underscore the considerable impact of birth weight on slaughtered and carcass weights, emphasizing the positive association between higher birth weights and enhanced carcass yield. Remarkably, despite these pronounced effects on carcass traits, the birth weight did not demonstrate a statistically significant influence on meat quality or overall muscle fibre characteristics, except for the area of Type I fibres in the LTL muscle. This nuanced understanding contributes valuable insights into the intricate relationship between birth weight and various physiological and carcass parameters in Karayaka lambs undergoing post-weaning fattening.

Determination of the effect of pre-mating weight and placental characteristics on birth weight in Karayaka sheep

The aim of this study was to determine the effect of the pre-mating weight and placental characteristics on birth weight. Data were collected from 62 Karayaka ewes and 70 Karayaka lambs. The placental characteristics considered were placental weight, placental area and the number of cotyledons. The Pearson correlation coefficient was used for statistical comparison and the determination of relationships between variables. In addition, correlation coefficients between live weights and placental characteristics were determined. The average birth weight (BW), pre-mating weight (PMW), placental weight (PW), placental area (PA) and cotyledon number (CN) values were 4.37 ±  0.70 kg, 50.22 ±  5.63 kg, 362.51 ±  118.42 g, 994.18 ±  312.76 cm2 and 56.93 ±  8.06, respectively. BW had positive correlations with PMW (0.147), birth type (BT) (0.643), PW (0.604), PA (0.323) and CN (0.161) (P  <  0.05). BW had negative correlations with maternal age (MA) (- 0.119 ) (P  <  0.05). PMW had positive correlations with maternal age (MA) (0.237) (P  <  0.05). PMW had negative correlations with S (sex) (- 0.003 ), PW (- 0.049 ), PA (- 0.067 ) and CN (- 0.080 ) (P  >  0.05).

A Missense p.Q>R234 Mutation in the Osteopontin Gene Is Associated With the Prolificacy of Iraqi Awassi Ewes

One of the most valuable traits in production and breeding is a sheep's prolificacy which is influenced by several genes, one of which is the osteopontin (OPN) gene. Thus, this study aimed to determine the effect of genetic variation within the OPN gene on Awassi ewe prolificacy. Genomic DNA was extracted from 123 single-progeny ewes and 109 twin ewes. Polymerase chain reaction (PCR) was used to amplify 4 sequence fragments (289, 275, 338, and 372 bp), representing exons 4, 5, 6, and 7 of the OPN gene. A 372 bp amplicon was identified with 3 different genotypes: TT, TC, and CC. Sequence analysis revealed a novel mutation in TC genotypes p.Q>R234. Statistical analysis revealed that the single nucleotide polymorphism (SNP) p.Q>R234 was associated with prolificacy. Ewes carrying the p.Q>R234 SNP had significantly (P ⩽ .01) lower litter sizes, twinning rates, and lambing rates, and more days to lambing than those with the TC and TT genotypes. The p.Q>R234 SNP was confirmed to be responsible for lower litter size through logistic regression analysis. From these results, we can conclude that the missense variant p.Q>R234 adversely affects the traits of interest and shows that the p.Q>R234 SNP negatively influences the prolificacy of Awassi sheep. Based on this study, it is evident that ewes in this population carrying the p.Q>R234 SNP have a lower litter size and are less prolific.

Farmers’ Risk Perception on Climate Change: Transhumance vs. Semi-Intensive Sheep Production Systems in Türkiye

Simple Summary

Adaptation strategies developed by sheep breeders against climate change are essential for sustainable production. This study was designed to determine the effects of climate change on perception, the risks of sheep farmers and the actions taken to mitigate these impacts. Nearly all farmers in both production systems agreed on the increased use of drugs and chemicals in their farming activities due to the increase in unknown and known disease outbreaks. The current study showed that transhumance farmers focused mainly on selling livestock as an adaptive strategy. In contrast, semi-intensive farmers concentrated on modifying their farm management and feed operations. Our findings show that semi-intensive farmers do not take deliberated and consistent action against climate change but adapt spontaneously.

Abstract

Sheep farmers’ perceptions of climate change and its impacts and the adaptation strategies they consider to address these risks are of great importance in ensuring the resilience of farming practice. This study focused on sheep farmers’ perception of climate change and the risks and actions taken to mitigate these impacts. A total of 68 surveys were carried out among sheep farmers (39 transhumance and 29 semi-intensive farmers) by two different representative production systems in Türkiye. Variables regarding the socio-economic profile, climate change impacts, and adaptation strategies were identified and analyzed. Principal component analysis and a Pearson Chi-square test were used to evaluate the data. Both farmers’ groups accepted and perceived climate change, showing good awareness and perception. The farmers’ attitudes towards adaptation to climate change were associated with production systems. Transhumance farmers had limited adaptation and coping strategies compared to semi-intensive farmers. Transhumance farmers focused mainly on selling livestock (mostly to cope with degraded natural grassland/feed deficiency) as an adaptive strategy. In contrast, semi-intensive farmers focused on modifying their farm management and feed operations, such as changing the feed ratio and supplement use, improving water and feed storage, and considering crop feed production. The knowledge obtained from this study could be helpful for farmers and policymakers who develop long-term small ruminant production strategies that consider the effects of climate change and adapt them to different farming systems in the Türkiye.