Growth Characteristics Of Lambs Research Articles

Fertility and Some Growth Characteristics of Lambs in Akkaraman Sheep Grown in Çorum Province

Objective: The aim of this study was to determine the reproductive efficiency and lamb growth characteristics of Akkaraman sheep in Çorum province under breeder conditions. Material and Methods: The animal material of the study consisted of 2214 Akkaraman sheep and 2508 Akkaraman lambs from three different farms located in the center of Çorum province. The study was conducted between 2019 and 2022. In the study, reproductive characteristics of Akkaraman sheep and birth, weaning live weights, and survival of lambs were determined. Results: The mean birth weight of lambs was 4.15 kg, and the mean weaning weight (75th day) was 19.58 kg. Birth and weaning weights differed according to year, farm, type of birth, and sex (P

Production performance analysis of sheep MSTN gene C2361T locus

The myostatin (MSTN) gene exhibits significant nucleotide sequence variations in sheep, impacting growth characteristics and muscular traits of the body. However, its influence on specific growth traits in some sheep remains to be further elucidated. This study utilized single nucleotide polymorphism sequence analysis to investigate the role of the MSTN gene in meat production performance across four sheep breeds: Charolais sheep, Australian White sheep, crossbreeds of Australian White and Small-tailed Han, and crossbreeds of Charolais and Small-tailed Han. At a SNP locus of the MSTN gene, the C2361T site was identified, with three genotypes detected: CC, CT, and TT, among which CC predominated. Gene substitution effect analysis revealed that replacing C with T could elevate the phenotypic value. Comparative analysis of data from different genotypes within the same breed highlighted the superiority of CC and TT genotypes in phenotypic values, underscoring the significance of specific genotypes in influencing key traits. Contrasting the performance of different genotypes across breeds, Charolais sheep and Charolais Han hybrids demonstrated superiority across multiple indicators, offering valuable insights for breeding new sheep varieties. Analysis of gender effects on growth characteristics indicated that ewes exhibited significantly wider chest, waist, and hip widths compared to rams, while rams displayed better skeletal growth and muscle development. Additionally, the MSTN gene also exerted certain effects on lamb growth characteristics, with the CC genotype closely associated with weight. These findings not only contribute crucial insights for sheep breeding but also pave the way for future research exploring the interaction of this gene with others.

Detecting Polymorphisms of Mutation (C519T) Sit 112480 of Gene Foxo3 and its Associations with Reproductive Performance of Awassi Sheep

The current study was conducted on a sample of 45 local Awassi ewe, with ages ranging from 2-4 years. These ewes produced 54 newborns, and the ages and weights of these newborns were monitored from birth until the sixth month of life for the period from 1/5/2022 to 6/25/2022 at Al-Fayhaa Sheep Station / Babylon Agricultural Directorate / Ministry of Agriculture. As for laboratory analyzes, they were conducted in the laboratories of the Scientific Advancement Company for Molecular Genetics for the period from 1/5/2022 to 6/25/2022. For the purpose of extracting DNA material, and determining the genotypes of the Foxo3 gene through the genotype of the mutation (Sit 112480)) T519C and studying the effect of this mutation on the studied characteristics, which are daily milk production (DMY), milk components, growth characteristics of lambs (different weights and ages), the rate of weight gain between weights mentioned above, growth rate, live mothers’ weights, mothers’ body dimensions, type of delivery (twins or singles). This formed mutation, which was found in the second segment of exon No. 2 of the Foxo3 gene, was amplified with a size of 420 bp N-hall using the nucleotide sequencing technique. This mutation produced three genotypes (TT, TC, and CC), and the ratios of genotypes were (0.00, 53.66, 46.34), sequentially. The variance between these ratios was highly significant (p≤0.01), and the allelic frequency was 0.27, 0.73 for both the T and C alleles. It was clear from the results that the effect of the different genotypes of the Foxo3 gene was not significant for the characteristic of daily milk production, and some other components of milk except for the percentage of fat were significant (p≤0.05). Weight between birth weight and weaning weight, and the results also show that there are significant differences for the type of birth characteristic (P≤0.05). There were no significant differences in the different genotypes of the Foxo3 gene for the characteristics represented by the body dimensions of the mothers and the live weight of the mothers, as well as the growth characteristics of the lambs, which are represented by the weight for the first three months of life and the rate of weight gain between them. It can be concluded from the previous results of this study the possibility of adopting the distinct genotypes of the Foxo3 gene for this genotype in the genetic improvement programs of the studied Awassi sheep to obtain the best economic return by selecting and cross-crossing the distinct genotypes in the characteristics that achieved the best ratios as well as the weight rates.

Relationships between growth-related traits with carcass and meat quality traits in Spanish Assaf suckling lambs

Suckling lamb meat is a relevant product in Mediterranean European dairy sheep farms, and the dairy breed Spanish Assaf is widely extended through the Iberian Peninsula. Knowledge of the influence of birth body weight (bBW) and growth rate on suckling lamb carcass and meat quality is scarce, but useful for breeding optimisation and product homogeneity. In turn, these growth-related traits of lambs might be affected by dietary restrictions of their dams. In this study, 34 male Assaf suckling lambs born from two groups of ewes that had been fed diets with different protein levels when they were prepubertal female lambs (17 lambs per group) were analysed. After birth, the suckling lambs were fed ad libitum on milk replacer until their sacrifice (10–12.5 kg live body weight). The quality traits evaluated in carcasses and meat were carcass compactness, fatness and jointing, meat composition, colour, texture and oxidative stability, and fatty acid profile. The dam group did not show significant effects on lamb growth characteristics or carcass and meat quality traits. The bBW factor showed a negative effect on leg subcutaneous fatness and a positive effect on the forequarter and shoulder percentages of the carcass. The bBW also resulted in increased moisture, lipid oxidation stability, and n-3 FA content (lowering the n-6/n-3 ratio) in the meat. Suckling lambs showing very low average daily gain (ADG) tended to present low carcass quality, i.e., higher bone percentage in the loin and low percentages of muscle or fat compared to those showing high ADG. Further studies are needed to confirm and explain the mechanisms of the significant effects reported here for bBW and ADG on the affected quality traits.

The polymorphism of insulin-like growth factor-1 receptor (IGF-1R) gene in meat-type Lambs in Turkey: I. Effect on growth traits and body measurements

As an important tyrosine kinase activator, insulin-like growth factor-1 receptor (IGF-1R) is activated by IGF-1 and IGF-2 and is a cell surface protein that functionally regulates cell growth and proliferation. This study was conducted to investigate the association between the previously determined single nucleotide polymorphism (SNP; g 0.195C > T) in the IGF-1R gene with growth and skeletal development traits of meat-type lambs. Different sheep breeds and their crosses were involved in the study, and data were collected from a total of 159 lambs (62 males and 97 females). The selected region in IGF-1R was analyzed using PCR-RFLP and the SNP g 0.195C > T substitution was detected. Subsequently, three genotypes were determined for this genetic variation: AA (0.197), AB (0.493), and BB (0.310). The associations between the identified genotypes and growth traits were evaluated for the period from birth to PS (pre-slaughter). Statistical analysis showed that IGF-1R genotypes had a significant effect on birth weight (P < 0.01) and daily weight gain on day 90- PS (P < 0.05). Similarly, the effects of genotype on body measurements, withers height and back height were significant (P < 0.05). In ultrasound measurements, longissimus dorsi (LD) muscle depth, skin thickness, and fat thickness were not significant. The data obtained in this study show that the variation of IGF-1R gene has a significant effect on the growth characteristics of lambs. Therefore, the use of this gene as a genetic marker in the production of lambs for slaughter may lead to more profitable production.

Reproductive and Growth Characteristics During The First Age of Kıvırcık, Sakız and Gökçeada Indigenous Sheep Breeds

This study was conducted to determine first age reproduction characteristics of indigenous Kıvırcık, Sakız and Gökçeada sheep breeds and growth performances of ewe lambs which have been kept in Bandırma Sheep Research Station (BSRS). The data of reproduction characteristics of ewes and growth characteristics of lambs were collected on 15 Kıvırcık, 8 Sakız and 10 Gökçeada ewes, and on 16 Kıvırcık, 12 Sakız and 11 Gökçeada lambs, respectively. After the lambs completed their fifth month ages, estrus detection was carried out with a teaser ram twice a day with 12 hour intervals. For the Kıvırcık, Sakız and Gökçeada lambs, the first oestrus weights were 37.93, 33.35 and 29.75 kg; first oestrus ages were 315, 320 and 337 days; oestrus durations were 30.99, 25.85 and 20.28 hours and the duration of the oestrus cycles were 16.59, 19.91 and 17.76 days, respectively. The birth weights of Kıvırcık, Sakız and Gökçeada lambs were found to be 3.64, 3.91, 3.28 kg; the weaning weight (WW), 31.01, 25.44 and 23.67 kg, the six month live weight (SMLW), 32.87, 26.95 and 24.15 kg, the yearling live weight (YLW), 39.01, 30.95 and 30.27 kg and the average daily weight gain (ADWG), 0.271 0.257 and 0.202 kg, respectively.

Relationship between birth weight and body growth characteristics of lambs

Research was carried out in population of R2 generation Pirot pramenka x Pirot improved sheep during period of three years. Lambs were divided into three groups: I from 2.5 kg to 3.5 kg; II from 3.6 kg to 4.5 kg; III from 4.6 kg to 5.5 kg. Weight of lambs was controlled at birth, with 30, 60 and 90 days of age. Average body weight at birth of the tested lambs was 3.35 kg in the first group, 4.30 kg in the second group and 5.06 kg in the third group. At 30 days of age, the body weight of the lambs was 10.19 kg in the first group, 11.39 kg in the second and 12.49 kg in the third group. All these differences in body weight of lambs at birth were statistically highly significant (P_ 0.01). With 60 days of age, average body weight was 16.48 kg in the first group, 19.01 kg in the second and 20.49 kg in the third group. Differences between groups of lambs at this age were statistically very significant (P_0.01).On the end of experiment at 90 days of lambs age, we have found the following values of the body weight of lambs: 26.35 kg in the first group, when the second 30.49 kg and 28.93 kg in the third group. Differences between groups of lambs at this age were statistically very significant (P_0.01). At the age of 90 days maximum weight of the body was in the second group of lambs, or a group which body weight at birth occupied the mean of the population. Correlations between body weights of lambs vary from weak to midsized values. The highest values of correlation coefficients were found between body weight at birth and weight of lambs at 30 days of age.

Phenotypic and genetic parameters for growth characteristics of Morkaraman sheep

The aims of the study were to determine heritabilities of growth characteristics and growth characteristics of Morkaraman sheep raised by local breeders in Erzurum province between 2006 and 2010. Growth characteristics such as live weight and daily live weight gains of Morkaraman lambs in the various periods were examined for this purpose. The effects of some environmental factors such as herd type, sex, birth type and years on these characteristics were also examined. In the study, growth characteristics of lambs obtained from mating of 5339 ewes and 253 rams were measured based on performance tests and a selection practice was performed. Elite, multiplier flock and commercial herds were established. The heritabilities of traits in question were determined. The breeding value for daily live weight gains up to the end of grazing season in the fifth year was calculated. Birth weight, birth weight heritability, weights and weight heritability at the beginning of grazing season, weight and weight heritability at the end of grazing season, daily live weight gain up and daily live weight gain heritability to the beginning of grazing season, daily weight gain up and daily live weight gain heritability to the end of grazing season were found 3.5±0.01 kg, 0.26±0.149, 21.4±0.07 kg and 0.41±0.103, 37.4±0.09 kg and 0.43±0.138, 239±1.33 g and 0.48±0.083, 201±0.78 and 0.47±0.082, respectively. At the end of the research, to improve the growth characteristics of Morkaraman sheep and to increase live weight gain to be obtained from each lamb were targeted. As a result, the live weights at the end of grazing season of lambs, Morkaraman provided an increase of approximately 5 kg. In terms of examined growth characteristics of Morkaraman sheep measured by individual performance testing, it is determined that Morkaraman sheep can be breeded by local breeders to improve its growth traits.

Karacadağ Yöresinde Yetiştirilen Zom Koyunlarının Üreme Performansı ve Kuzularının Büyüme Özellikleri

Karacadağ Yöresinde Yetiştirilen Zom Koyunlarının Üreme Performansı ve Kuzularının Büyüme Özellikleri

Growth characteristics in lambs of estrus synchronized ewes in grower conditions

The aim of this study was to determine the growth characteristics of lambs of estrus-synchronized ewes in an extensive production system during 2 different periods. The animal material of this study was composed of 325 head Chios × Kıvırcık cross breeds. These lambs were provided by mating 124 Kıvırcık sheep on 2 farms with 8 Chios rams provided by the Adnan Menderes University, Faculty of Agriculture, Sheep Research Unit. The estrus cycles of the ewes were synchronized with intra-vaginal progestagen sponges impregnated with 30 mg of cronolone. After 12-14 days the sponges were removed, the females received an intramuscular injection of 500 IU PMSG, and 5 or 6 ewes were mated with Chios rams. This research lasted for 3 years, and detailed flock records were kept. The average birth weight, average weight of 100-day-old lambs, and average marketing weight of Kıvırcık × Chios F1 were 3.18 kg, 19.71 kg, and 29.10 kg, respectively. Lambing season, birth type, and the sex of the lambs were found to significantly affect birth weight, which is an important factor in lamb production (P < 0.01). In this study daily gains in the live-weight of 100-day-old lambs and daily gains in the live-weight during the marketing period were 163.07 g and 167.48 g, respectively. Year of birth, lamb sex, and growing methods were significant in determining the characteristics mentioned (P < 0.01). In addition, the 100th day performances indicated significant changes according to the farms, and the performances during the marketing period varied significantly according to the ages of the ewes. The survival rates of lambs up to 100 days of age and the marketing period were 66.81% and 63.57%, respectively. The effect of year was also significant (P < 0.01). The results of this study indicate that, with respect to lamb development and marketing, more advantageous results can be achieved by synchronizing estrus and having earlier births than traditional production methods allow.

Comparison of Lamb Growth Characteristics in Diverse Genotypes in Relation to Milk Yield of Dams

Comparison of Lamb Growth Characteristics in Diverse Genotypes in Relation to Milk Yield of Dams

Effects of maternal uterine environment and genotype on gestation length, lambing ease and growth characteristics of lambs

Perinatal lamb mortality remains a major welfare and economic concern for the sheep farming industry. The vitality and teat-seeking abilities of the newborn lamb are fundamental to its survival and are likely to be greatly influenced by its physical characteristics and ease of birth. The following experiment used embryo-transfer techniques to distinguish between maternal and foetal genotype and environmental factors affecting gestation length, lambing ease and postnatal growth in two breeds of sheep with differing ewe and lamb liveweights.Thirty-eight Scottish Blackface (BF; mean liveweight (±s.e.m.) at lambing=54.25 kg ±1.03) and 41 Suffolk ewes (S; 80.33 kg ± 1.52) were given single purebred embryos obtained from 17 donor ewes and 10 sires. Embryos were transferred between ewes in a balanced design such that the following combinations were obtained: 18 BF ewes with BF lambs; 20 BF ewes with S lambs; 20 S ewes with BF lambs; 21 S ewes with S lambs.

Effects of maternal uterine environment and genotype on gestation length, lambing ease and growth characteristics of lambs

Perinatal lamb mortality remains a major welfare and economic concern for the sheep farming industry. The vitality and teat-seeking abilities of the newborn lamb are fundamental to its survival and are likely to be greatly influenced by its physical characteristics and ease of birth. The following experiment used embryo-transfer techniques to distinguish between maternal and foetal genotype and environmental factors affecting gestation length, lambing ease and postnatal growth in two breeds of sheep with differing ewe and lamb liveweights.Thirty-eight Scottish Blackface (BF; mean liveweight (±s.e.m.) at lambing=54.25 kg ±1.03) and 41 Suffolk ewes (S; 80.33 kg ± 1.52) were given single purebred embryos obtained from 17 donor ewes and 10 sires. Embryos were transferred between ewes in a balanced design such that the following combinations were obtained: 18 BF ewes with BF lambs; 20 BF ewes with S lambs; 20 S ewes with BF lambs; 21 S ewes with S lambs.