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Öğe Comparative genomic characterization of indigenous fat-tailed Akkaraman sheep with local and transboundary sheep breeds(Wiley, 2024) Kızılaslan, Mehmet; Arzık, Yunus; Behrem, Sedat; White, Stephen N.; Çınar, Mehmet UlaşThe domestic sheep with over 1200 breeds descended from those early domesticated animals that are bred for a variety of resources such as meat, milk and wool. Akkaraman, a fat-tailed indigenous sheep breed of Turkiye, is widespread throughout Central Anatolia, with the largest indigenous sheep population. Assessing the genetic diversity and genomic structure of animal breeds is among the key contributors to deciphering adaptation to environmental extremes and constructing efficient genetic improvement strategies. Therefore, this study aimed to characterize the genome of Akkaraman breed against various world-renowned transboundary sheep and indigenous sheep with fat and thin tails. Genetic similarities and differences between those breeds have been displayed by estimating and comparing various genetic diversity indices, linkage disequilibrium (LD) estimates and fixation index (FST), runs of homozygosity (ROH) as well as PCA and neighbour-joining tree analysis. Akkaraman sheep were observed to form a cluster alongside Moghani, Karakas, Tibetan and Cyprus Fat Tail sheep, which are primarily the sole representatives of fat-tailed sheep in the study. This clustering was evident in both the PCA and neighbour-joining tree analysis. The Akkaraman sheep was also observed to have the lowest genomic inbreeding and one of the lowest numbers of ROHs, which might also indicate that the breed has not been exposed to historical intensive selection pressure, inbred mating or a massive population bottleneck that might leave strong marks of genomic homozygosity. The results improve our understanding of the genetic diversity in Akkaraman sheep in comparison with certain mainstream sheep breeds as well as those indigenous breeds from around the world. Additionally, findings will also provide valuable insights to perform further GWAS effectively by considering population structure, diversity and LD patterns observed among the breeds while providing practical knowledge that will contribute to designing efficient and successful genome-based selection programmes for worldwide sheep production systems.Öğe Comparison of reproductive performance, live weight, survivability, and fleece characteristics of indoor-raised Central Anatolian Merino and Malya sheep(Sociedade Brasileira de Zootecnia, 2022) Behrem, Sedat; Tuncer, Selçuk Seçkin; Şenyüz, Hasan HüseyinThis study was conducted to compare Central Anatolian Merino (CAM) and Malya sheep under intensive conditions in terms of reproductive traits, birth and weaning weights, fattening performance, and some fleece characteristics. In this study, 840 CAM and 194 Malya ewes were used for the comparison of reproductive performance, whereas 740 and 211 lambs were used to compare growth traits between the two breeds. Additionally, the fattening performance of 61 CAM and 68 Malya lambs were compared. Finally, for the comparison of wool quality traits, 94 CAM and 90 Malya lambs were used. The lambs were kept together with the sheep that gave birth to them for 10 days. After this period, lambs were given lamb starter feed, alfalfa hay, and vetch hay in addition to milk. When lambs reached 40 days old, they were taken to the pasture with the sheep. In this period, pasture grass, growing lamb concentrate feed, alfalfa hay, and vetch hay were given in addition to milk. Lambs were weaned when they reached an average age of 90 days, and their live weights were determined. A determined number of lambs was selected from weaned male lambs. For these animals, in the fattening period, barley, alfalfa hay, vetch hay, meadow hay, and lentil straw were provided ad libitum in addition to 400 g/day/head of fattening feed. This study indicated that birth rate was better for CAM sheep than for Malya sheep. However, Malya lambs may have more advantages than CAM lambs in terms of survival and fattening performance. Although birth weight was higher for Malya sheep than for CAM sheep, the opposite result was observed for the weaning weight. The beginning weights of fattened male lambs were higher for CAM lambs than for Malya lambs, but the ending weights of both fattened groups were similar.Öğe Economic Evaluation of Mohair Production in Ankara Province(Hasan ÖNDER, 2023) Arzık, Yunus; Behrem, Sedat; Kızılaslan, MehmetAngora goat is the most important goat breed that spread from Central Asia to Anatolia and became a part of Turkish culture. Angora goat, which is thought to have been brought to Anatolia in the 13th century, is intensively raised in the Central Anatolian region, especially in Ankara and its surroundings. In this study, it is aimed to give information about the distribution of the goat population according to Ankara province and its districts, the amount and price of mohair purchase by years, and the fiber quality of Angora goats raised in the region. According to the findings, it has been observed that there is an increase in the number of Angora goats in Ankara parallel with the total number of small ruminants in Türkiye. When the farms that are members of the Ankara Sheep and Goat Breeders' Association are examined, Ankara goat breeding is carried out in almost all districts of Ankara. The number of Ankara Goats, which was approximately 158 thousand in 2012, reached approximately 289 thousand in 2021. Between 2016 and 2021, a total of 48814.00 kg of mohair was obtained from Ankara Goats in Ankara. Furthermore, when mohair prices are analyzed in dollars, it is determined that the highest price was in 2019, and the amount of subsidy given by the State decreased over the years. In terms of literature, we can say that there are not enough new studies on Angora goats and that up-to-date studies are needed. The fact that Ankara is suitable for goat breeding due to its geography and that the importance of goat breeding for those living in rural areas in cultural terms has ensured the continuity of Ankara Goat production. Although the goat population seems to be increasing in the last 10 years, there has been a serious decrease compared to the beginning of the 1900s. Necessary studies should be done properly in order to increase the Angora goat population.Öğe Effects of age and body region on wool characteristics of Merino sheep crossbreds in Turkey(Scientific and Technological Research Council of Turkey, 2022) Behrem, Sedat; Gül, SabriAim of this study was to comparatively investigate the wool characteristics of Central Anatolian Merino, Karacabey Merino and Ramlic sheep, which are common crossbred sheep breeds in Turkey. A total of 360 wool samples were equally collected from the shoulder, rib, and rump of each lamb (3-6 months-age), yearlings (1-1.5-year age), primiparous ewes (2-2.5-year age) and multiparous ewes (3-3.5-year age) were used for analysis. Each sample was analyzed to determine fibre diameter, length, clean fleece yield, elasticity, and strength. Also, live weight after shearing and greasy fleece weights were recorded for each animal. Statistical analysis of this study was performed using SPSS software. Normality hypothesis tested using the Shapiro-Wilk test. Homogeneity of the variance for each trait was tested with the Levene's test. Descriptive statistics of the traits were given as mean +/- standard error. Observed means for greasy fleece weight were 3.6 +/- 0.09 kg, 2.5 +/- 0.09 kg, and 2.2 +/- 0.08 kg for Karacabey Merino, Central Anatolian Merino and Ramlic sheep, respectively. Average diameter, length, clean fleece yield, elasticity, and strength measurements of Karacabey Merino were 23.9 +/- 0.11 mu, 59.2 +/- 0.64 mm, 56.2 +/- 0.35%, 20.2 +/- 0.23 cN / tex, and 12.6 +/- 0.09 cN / tex, whereas 24.7 +/- 0.12 mu, 50.6 +/- 0.71 mm, 55.2 +/- 0.60%, 21.6 +/- 0.23 cN / tex, 13.8 +/- 0.14 cN / tex in Central Anatolian Merino and 24.1 +/- 0.12 mu, 53.2 +/- 1.05 mm, 62.9 +/- 0.53%, 22.3 +/- 0.26 cN / tex, 13.4 +/- 0.12 cN / tex were observed in Ramlic sheep, respectively. This study suggests that observed wool characteristics for each of three crossbreds were within the standard range of the textile industry. Therefore, all three crossbreds were suggested to be considered for the development of new agricultural policies and increasing breeder's awareness to reintroduce these crossbreds in the textile industry.Öğe Effects of age, body region and mineral contents on the fleece characteristics of central anatolian merino sheep(Ege University, 2022) Behrem, Sedat; Keskin, Mahmut; Gül, Sabri; Ünay, Engin; Erişek, AbdulkadirThe fibre characteristics of fleece determine its fate through the textile industry. Parameters such as diameter, length, elasticity and strength define the functional quality of fleece. Therefore, the aim of the present study was to investigate effects of different environmental factors as well as wool mineral contents on fleece fibre quality traits in Central Anatolian Merino sheep (CAM). Additionally, the mineral contents of CAM fleece were investigated. For this purpose, 300 samples were equally collected from 3 different body regions (shoulder, rib and rump) of 100 animals from five different age groups. Samples were analysed for fibre quality (diameter, length, elasticity and strength) traits and mineral contents (calcium, iron, potassium, magnesium, copper, manganese and zinc). A wide range of statistical relationships were found among the focused traits and those factors. The findings of this study highlight the importance of minerals as well as environmental factors on fleece qualityparameters.Öğe Exploring Genetic Factors Associated with Moniezia spp. Tapeworm Resistance in Central Anatolian Merino Sheep via GWAS Approach(Multidisciplinary Digital Publishing Institute (MDPI), 2025) Arzık, Yunus; Kızılaslan, Mehmet; Behrem, Sedat; Piel, Lindsay M. W.; White, Stephen N.; Çınar, Mehmet UlaşGastrointestinal parasite (GIP) infections are a major challenge in pasture-based sheep farming, leading to both economic losses and animal welfare concerns. This study aimed to identify genetic factors that contribute to resistance against tapeworm (Moniezia spp.) infections in Central Anatolian Merino (CAM) sheep. We conducted genome-wide association studies (GWAS) on 226 CAM lambs, analyzing their genetic data in relation to Moniezia spp. egg burden. Thirteen significant genetic markers (SNPs) were identified. Two key immune-related genes, CD79A and MAP3K7, were linked to parasite resistance. CD79A is essential for B-cell activation and antibody production, while MAP3K7 regulates immune responses, particularly through NF-κB signaling. These findings highlight the potential for using genetic information to improve disease resistance in livestock breeding programs. Further research is needed to understand the role of these genes and to explore host–parasite interactions in more detail.Öğe Exploring the economically important growth traits and environmental influences on akkaraman lambs in Ankara(Sezer ÖZ, 2024) Kızılaslan, Mehmet; Arzık, Yunus; Behrem, SedatThis study focused on the Akkaraman sheep breed, specifically examining the pre-weaning growth characteristics and Kleiber ratio, within the framework of Türkiye’s National Community-Based Small Ruminant Breeding Program. The research involved Akkaraman lambs born between 2017 and 2021 across 20 farms in the Ankara province. The dataset comprised 19,119 observations, covering key attributes such as birth weight, weaning weight, average daily weight gain, and the Kleiber ratio. Statistical analyses were conducted to identify outliers, assess normality, and develop linear models to explore the impact of environmental factors on the traits. Birth weight was significantly influenced by sex, birth type, birth season, birth year, and flock size. Weaning weight exhibited significant variations based on the same factors, emphasizing the importance of gender, birth type, birth season, birth year, and flock size. Average daily weight gain was notably affected by gender, birth type, birth season, birth year, flock size, and environmental factors, emphasizing their impact on growth. The Kleiber ratio demonstrated significant variations influenced by gender, birth type, birth season, birth year, and flock size. The results highlighted the intricate interplay between environmental factors and pre-weaning growth traits in the Akkaraman sheep breed. The study contributes valuable insights to enhance productivity and underscores the potential of the Akkaraman breed in Türkiye's overall agricultural development, considering its adaptability to arid climates and challenging pasture conditions.Öğe Exploring the polygenic landscape of wool traits in Turkish Merinos through multi-locus GWAS approaches: middle Anatolian Merino(Nature Research, 2025) Yaman, Yalçın; Önaldı, A. Taner; Doğan, Şükrü; Kırbaş, Mesut; Behrem, SedatThis study investigates the genetic underpinnings of wool traits, specifically fibre diameter (FD) and staple length (SL), in Middle Anatolian Merino sheep using multi-locus genome-wide association study (GWAS) approaches. Representing the first attempt to examine these polygenic traits with multi-locus methods, the analysis employed four techniques: mrMLM, FASTmrMLM, FASTmrEMMA, and ISIS EM-BLASSO. A total of 18 Quantitative Trait Nucleotides (QTNs) were identified for FD, with 7 co-detected by multiple methods, and 14 QTNs were identified for SL, with 5 co-detected by multiple methods. Post-hoc power analysis revealed high statistical power for both traits (FD: 0.95, SL: 0.91). Notably, three candidate genes—PTPN3, TCF4, and ZBTB8A—were found to be consistent with prior studies. Gene enrichment and pathway analyses reaffirmed the complex and multifactorial molecular mechanisms governing wool traits. These findings enhance our understanding of the polygenic nature of wool traits, shedding light on the intricate genetic regulation and pinpointing genomic regions potentially influencing wool physiology. By identifying specific QTNs associated with FD and SL, this research provides a foundation for elucidating the genetic mechanisms underlying these economically significant traits. Upon validation in diverse populations, these findings hold substantial promise for the application of marker-assisted selection (MAS) to improve wool traits.Öğe Genetic parameter estimation of preweaning growth traits in Akkaraman sheep(Springer Science and Business Media B.V., 2024) Arzık, Yunus; Behrem, Sedat; Sakar, Çağrı Melikşah; Ünal, İlkerThis study aimed to evaluate (co)variance components and heritability of pre-weaning body weight traits and the Kleiber ratio in Akkaraman sheep. Data collected between 2018 and 2023 from Çankırı province, Türkiye, formed the basis of this research. The considered traits were birth weight (BW), weaning weight (WW), average pre-weaning daily weight gain (ADWG), and Kleiber ratio (KR). Utilizing animal mixed models and the average information restricted maximum likelihood (AI-REML) procedure, genetic parameters were estimated. Direct heritability estimates were 0.30 ± 0.02, 0.23 ± 0.02, 0.23 ± 0.02, and 0.28 ± 0.03 for BW, WW, ADWG, and KR, respectively. Maternal genetic heritabilities were 0.03 for WW and 0.02 for WW, ADWG, and KR. Direct genetic correlations among pre-weaning growth traits were negative for BW-WW and BW-ADWG and positive for WW-ADWG at -0.05, -0.23, and 0.98, respectively. The moderate direct heritability estimate suggests the presence of genetic variability in the Akkaraman sheep breed, indicating potential genetic progress through selective breeding. Despite the low maternal permanent environmental effects, the significant impact of maternal care on lamb growth in this breed underscores the importance of considering both direct and maternal effects in the genetic evaluation of early growth traits. The observed negative genetic correlations among birth weight, weaning weight, and daily live weight gain until weaning emphasize the need for careful consideration in selection programs for the Akkaraman breed.Öğe Genetic parameters for ewe lifetime productivity traits in Central Anatolian Merino sheep(Elsevier B.V., 2024) Kızılaslan, Mehmet; Arzık, Yunus; Behrem, SedatRapidly increasing population size, recent breaks in production and supply chains, due to pandemics, and those further expected because of climate change emphasize the compelling importance of animal productivity. Traits associated with the productivity of ewes have a direct impact on the overall productivity, profitability and efficiency of sheep farms. Therefore, the objective of the current study was to estimate the variance components, heritabilities as well as genetic and phenotypic correlations, for traits associated with the lifetime productivity of Central Anatolian Merino ewes. Birth and weaning records of lambs for each ewe as well as environmental factors such as sex and birth type were utilized for deriving ewe lifetime productivity traits. Genetic parameter estimations involved observations from 3101 Central Anatolian Merino ewes, encompassing mean and total lamb birth weight per ewe (MBW and TBW), mean and total lamb weaning weight per ewe (MWW and TWW), and the mean and total number of lambs weaned (MNLW and TNLW). This analysis utilized a pedigree comprising 13229 animals. Average Information Restricted Maximum Likelihood (AIREML) based Animal Linear Mixed Model estimations for the decomposition of (co)variance components were implemented based on pedigree-derived numerator relationship matrix by also accounting for the number of parities as a fixed factor. Low to moderate heritability estimates, ranging between 0.29 and 0.42, were observed for the lifetime productivity traits of the breed. A wide range of genetic and phenotypic correlations (between ?0.56 and 0.99) was observed among the traits of interest. The outcomes of the study are anticipated to significantly enhance the global sheep production systems by uncovering the essential parameters for incorporating ewe's lifetime reproductive performance and productivity into the selection indices. This will also benefit Central Anatolian Merino farmers, who form a large proportion of sheep producers in Turkey.Öğe Genome-Wide Scan of Wool Production Traits in Akkaraman Sheep(MDPI, 2023) Arzık, Yunus; Kızılaslan, Mehmet; Behrem, Sedat; White, Stephen N.; Piel, Lindsay M. W.; Çınar, Mehmet UlaşThe objective of this study was to uncover the genetic background of wool quality, a production trait, by estimating genomic heritability and implementing GWAS in Akkaraman sheep. The wool characteristics measured included fibre diameter (FD) and staple length (SL) at the age of 8 months and yearling fibre diameter (YFD), yearling staple length (YSL) and yearling greasy fleece weight (YGFW) at 18 months of age. Animals were genotyped using the Axiom 50 K Ovine Genotyping Array. Maximum likelihood estimations of a linear mixed model (LMM) were used to estimate genomic heritability, where GWAS was conducted following a score test of each trait. Genomic heritability estimates for the traits ranged between 0.22 and 0.63, indicating that phenotypes have a moderate range of heritability. One genome- and six chromosome-wide significant SNPs were associated with the wool traits in Akkaraman lambs. Accordingly, TRIM2, MND1, TLR2, RNF175, CEP290, TMTC3, RERE, SLC45A1, SOX2, MORN1, SKI, FAAP20, PRKCZ, GABRD, CFAP74, CALML6 and TMEM52 genes as well as nine uncharacterized regions (LOC101118971, LOC105609137, LOC105603067, LOC101122892, LOC106991694, LOC106991467, LOC106991455, LOC105616534 and LOC105609719) were defined as plausible candidates. The findings of this study shed light on the genetics of wool quality and yield for the Akkaraman breed and suggests targets for breeders during systematic breeding programmes.Öğe Heritability and environmental influence on pre-weaning traits in Kilis goats(SpringerLink, 2023) Gül, Sabri; Arzık, Yunus; Kızılaslan, Mehmet; Behrem, Sedat; Keskin, MahmutBirth and weaning weights, average daily weight gain, and Kleiber ratio are important indicator traits in selection decision. The phenotypic expression of these traits is determined by the genetic background, environmental effects, and their interactions. The objective of this study was to estimate genetic parameters regarding birth (BW) and weaning weights (WW) and average daily weight gain (ADWG), Kleiber ratio (KR), and obtain the effects of sex, birth type, herd, and year. The data consisted of 2274 Kilis goats with pedigree information obtained from 53 bucks and 774 does in 4 generations. The restricted maximum likelihood (REML) procedure was conducted with an animal linear mixed model. Sex, birth type, herd, and year were found to be statistically significant (p value < 0.001) for all traits. Moderate direct heritabilities (ha2) for BW, WW, ADW, and KR were found to be as 0.18 ± 0.03, 0.50 ± 0.04, 0.47 ± 0.04, and 0.37 ± 0.05, respectively. The proportion of maternal permanent environmental effect (c2) to the total phenotypic variance (?2p) was estimated as 0.00 ± 0.00, 0.12 ± 0.02, 0.11 ± 0.02, and 0.18 ± 0.03 for BW, WW, ADWG, and KR, respectively. The genetic, phenotypic, and environmental correlations between the pre-weaning growth traits were found to be ranging from ? 0.02 to 0.99. Thus, our study suggests moderate heritabilities and positive and relatively high genetic correlations among the observed pre-weaning growth traits. These results have implications in terms of providing rapid genetic progress for these traits in breeding programs of Kilis goats.Öğe Investigation of Structural Characteristics of Central Anatolian Merino Sheep Farms and Effectiveness of the Breeding Project in Ankara Province(Sezer ÖZ, 2023) Zengin, Yusuf; Behrem, Sedat; Tütenk, Simge; Gül, SabriThe aim of this study is to determine the general characteristics and management and feeding practices of 33 Central Anatolian Merino sheep farms in Ankara within the scope of the "National Project for Community-based Small Ruminant Breeding" coordinated by General Directorate of Agricultural Research and Policies. Within the scope of this purpose, a survey consisting of a total of 78 questions was conducted with the farmers. The questionnaire consists of questions about general information about the farmers and farms, herd management, determination of the care and feeding methods of the animals and the effectiveness of the breeding project. At the end of the study, it was determined that 60% of the breeders were between the ages of 41-50, 90.91% of them were primary and secondary school graduates, and all of them kept regular records for herd management. Sheep breeders interviewed that they do supplemental feeding (approximately 34%) before mating and that they are milking by hand. Sheep breeders stated that they gained the habit of keeping records thanks to the breeding project, lamb rearing and breeding selection were made more effectively, so they benefited positively from the project. Furthermore, it was determined that the breeders wanted to stay in the project and wished for the project to continue.Öğe The environmental impact on economically significant traits in central anatolian merino sheep(Hasan ÖNDER, 2024) Arzık, Yunus; Behrem, Sedat; Kızılaslan, Mehmet; Tütenk, Simge; Yıldız, ÇağatayThis research delves into the pre-weaning growth and fleece characteristics of the Central Anatolian Merino sheep breed, focusing on Türkiye's National Community-Based Small Ruminant Breeding Program. The study encompasses Central Anatolian Merino lambs born between 2016 and 2021 across 22 farms in Ankara province, amassing a dataset of around 35,344 observations. Economically important traits such as birth weight (BW), weaning weight (WW), average daily weight gain (ADWG), Kleiber ratio at weaning (KR), fibre diameter, and fibre length (measured in approximately 4,809 observations) were scrutinized. Rigorous statistical analyses, including outlier identification, normality assessment, and the development of linear mixed models, were employed to unravel the impact of environmental factors on these traits. Significant findings emerged, indicating that birth weight, weaning weight, and the Kleiber ratio were substantially influenced by variables such as sex, birth type, birth season, birth year, and flock size. Moreover, average daily weight gain exhibited noteworthy variations attributed to gender, birth type, birth season, birth year, flock size, and other environmental factors, underscoring their collective impact on growth. Fleece traits displayed considerable diversity influenced by gender, birth type, birth season, birth year, and flock size. This study sheds light on the intricate interplay between environmental factors and pre-weaning growth traits within the Central Anatolian Merino sheep breed. Beyond its scientific contributions, this research provides valuable insights aimed at bolstering productivity. The adaptability of the Central Anatolian Merino breed to arid climates and challenging pasture conditions positions it as a key player in Türkiye's broader agricultural development.Öğe Unravelling the genetic architecture of serum biochemical indicators in sheep(Multidisciplinary Digital Publishing Institute (MDPI), 2024) Kızılaslan, Mehmet; Arzık, Yunus; Behrem, Sedat; Yavuz, Esra; White, Stephen N.; Çınar, Mehmet UlaşSerum biochemical indicators serve as vital proxies that reflect the physiological state and functions of different organs. The genetic parameters and molecular mechanisms underlying serum biochemical indicators of sheep (Ovis aries) have not been well understood. Therefore, the aim of the present study was to identify the genetic architecture and genomic loci underlying ten serum biochemical indicators in sheep, including alanine transaminase, aspartate transferase, lactate dehydrogenase, cholesterol, glucose, phosphorus, calcium, creatinine, urea and total protein levels. We implemented genetic parameter estimations and GWASs for each trait in 422 Akkaraman lambs. Overall, low to moderate heritability estimates were found in the range of 0.14–0.55. Additionally, low to high genetic correlations were observed among traits. In total, 23 SNP loci were associated with serum biochemical indicators leading to 19 genes. These were SPTA1, MGST2, CACUL1, IGFBP7, PARD3, PHB1, SLC15A5, TRIM35, RGS6, NUP93, CNTNAP2, SLC7A11, B3GALT5, DPP10, HST2ST1, NRP1, LRP1B, MAP3K9 and ENSOARG00020040484.1, as well as LOC101103187, LOC101117162, LOC105611309 and LOC101118029. To our knowledge, these data provide the first associations between SPTA1 and serum cholesterol and between ENSOARG00020040484.1 and serum glucose. The current findings provide a comprehensive inventory of the relationships between serum biochemical parameters, genetic variants and disease-relevant characteristics. This information may facilitate the identification of therapeutic targets and fluid biomarkers and establish a strong framework for comprehending the pathobiology of complex diseases as well as providing targets for sheep genetic improvement programs.Öğe Unveiling the Pre-Weaning Growth Performance and Some Reproductive Characteristics of Akkaraman and Central Anatolian Merino Sheep(Unveiling the Pre-Weaning Growth Performance and Some Reproductive Characteristics of Akkaraman and Central Anatolian Merino Sheep, 2025) Behrem, SedatThis study evaluated growth and reproductive traits in two sheep breeds in Türkiye, Akkaraman (AKK) and Central Anatolian Merino (CAM), with a focus on the impact of non-genetic factors. Data were analysed from 21,414 AKK and 20,099 CAM lambs for birth weight (BW) and 27,528 AKK and 24,639 CAM lambs for weaning weight (WW), average daily weight gain (ADWG) and Kleiber ratio (KR) using a linear mixed model. AKK lambs showed a significantly higher mean BW (4.19 ± 0.01 kg) than CAM lambs (4.02 ± 0.01 kg) (p < 0.001), whereas CAM lambs had significantly higher WW, ADWG and KR (p < 0.001 for each trait). Fixed effects of sex, birth type, dam age, birth year, herd size and season significantly influenced all growth traits (p < 0.05). Male lambs demonstrated higher BW, WW, ADWG and KR than females (p < 0.001), and single-born lambs had significantly higher BW and WW than twins (p < 0.001). Dam age also influenced all growth traits, with lambs from younger dams tending to be heavier (p < 0.001). In terms of survival, AKK lambs exhibited a significantly higher survival rate (93.85%) than CAM lambs (89.50%) (p < 0.001). Conception rates were similar for both breeds (92.9% for AKK and 92.3% for CAM), whereas CAM lambs showed higher fecundity and litter size. These findings underscore the breed differences in growth and reproductive traits and highlight the importance of considering non-genetic factors to inform breed-specific management practices aimed at optimizing productivity.
