Reproductive Performance Of Sheep Research Articles

The relationship of hematological parameters with adaptation and reproduction in sheep; A review study

Sheep possess desirable characteristics for farmers such as resistance to disease, good acclimation to environmental fluctuations, and endurance to extreme weather. This may, in part, be due to hematology characteristics and various types of hemoglobin that interact differently to external changes; displaying various reproductive ability in certain environmental conditions. This review aims to investigate the effect of hematology parameters and hemoglobin types on the adaptation and reproductive performance of sheep. Hematological parameters are useful tools for the detection of adaptation and physiological traits of these animals. The reproduction of sheep has depended on the ability of each type and breed to acclimate to different environmental conditions. In addition, hemoglobin types have also been correlated with the environmental adaptability and physiological traits of sheep. Thus, the present review provides useful information on the association of hematology parameters and hemoglobin types in sheep with adaptation and reproductive performance, and could be used as vital tools that help in determining the species or breed of sheep that are more adapted to certain environments or have more reproductive potential.

Pineal gland transcriptomic profiling reveals the differential regulation of lncRNA and mRNA related to prolificacy in STH sheep with two FecB genotypes

BackgroundLong noncoding RNA (lncRNA) has been identified as important regulator in hypothalamic-pituitary-ovarian axis associated with sheep prolificacy. However, little is known of their expression pattern and potential roles in the pineal gland of sheep. Herein, RNA-Seq was used to detect transcriptome expression pattern in pineal gland between follicular phase (FP) and luteal phase (LP) in FecBBB (MM) and FecB++ (ww) STH sheep, respectively, and differentially expressed (DE) lncRNAs and mRNAs associated with reproduction were identified.ResultsOverall, 135 DE lncRNAs and 1360 DE mRNAs in pineal gland between MM and ww sheep were screened. Wherein, 39 DE lncRNAs and 764 DE mRNAs were identified (FP vs LP) in MM sheep, 96 DE lncRNAs and 596 DE mRNAs were identified (FP vs LP) in ww sheep. Moreover, GO and KEGG enrichment analysis indicated that the targets of DE lncRNAs and DE mRNAs were annotated to multiple biological processes such as phototransduction, circadian rhythm, melanogenesis, GSH metabolism and steroid biosynthesis, which directly or indirectly participate in hormone activities to affect sheep reproductive performance. Additionally, co-expression of lncRNAs-mRNAs and the network construction were performed based on correlation analysis, DE lncRNAs can modulate target genes involved in related pathways to affect sheep fecundity. Specifically, XLOC_466330, XLOC_532771, XLOC_028449 targeting RRM2B and GSTK1, XLOC_391199 targeting STMN1, XLOC_503926 targeting RAG2, XLOC_187711 targeting DLG4 were included.ConclusionAll of these differential lncRNAs and mRNAs expression profiles in pineal gland provide a novel resource for elucidating regulatory mechanism underlying STH sheep prolificacy.

Polymorphisms in BMPR-IB gene and their association with litter size trait in Chinese Hu sheep

Identification and utilization of sheep major fecundity genes offer opportunities for the increase in litter size, as well as the improvement of production efficiency in livestock industry. BMPR-IB gene belongs to the TGF-β superfamily, and is also considered as a regulator for sheep reproductive performance due to its involvement in the mammalian gametogenesis pathway. This study aimed to detect the variations of BMPR-IB gene in Hu sheep (N = 934) and to evaluate their effects on the litter size trait. qRT-PCR results showed that the mRNA expression level of BMPR-IB in kidney was the highest. And in the tissues of ovary and pituitary, the expression levels of prolific group were significantly higher than that of non-prolific group (p < 0.05). Through DNA sequencing and PCR-RFLP, three SNPs were identified in the genomic region of BMPR-IB gene; the individuals with CC in g.29362047T > C, AA in g.29427689G > A and GG in FecB had better fecundity characterization. Additionally, association analysis indicated that two diplotypes of Hap2/2 and Hap2/4 showed larger litter size. Overall, our results verified several useful markers which would contribute to further development of sheep breeding strategies.

Effects of season and breed on the reproductive performance of sheep

Effects of season and breed on the reproductive performance of sheep

Study on the correlation between BMPR1B protein in sheep blood and reproductive performance.

Sheep reproductive performance is one of the important economic traits in sheep farming. The bone morphogenetic protein receptor 1B (BMPR1B) gene and protein may play an important role in sheep fertility. This study was to investigate the association of blood BMPR1B protein expression with reproductive performance in sheep. Mongolian sheep with single and twin births and polytocous Small Tail Han sheep were selected due to differences in birth numbers. The BMPR1B mRNA in sheep blood was measured by a reverse transcription-polymerase chain reaction as well as the BMPR1B protein was measured by enzyme-linked immunosorbent assay in blood samples of Mongolian and Small Tail Han sheep. The results demonstrated that blood BMPR1B concentration in Mongolian sheep with twin birth was higher (P < 0.05) than Small Tail Han sheep and Mongolian sheep with single birth. The protein concentration in the anestrus season was higher (P < 0.045) than those in the estrus season for both Mongolian and Small Tail Han sheep. Moreover, BMPR1B concentration in Mongolian sheep increased (P < 0.05) at the age of 6 to 12 mo and that in Small Tail Han sheep increased (P < 0.05) at the age of 3 to 6 mo. The result indicates that the increase in BMPR1B protein concentrations in the blood of Mongolian ewes and Small Tail Han ewes may be beneficial to follicular development, but too high or too low of this blood protein concentration in Mongolian and Small Tail Han sheep is not conducive to ovulation.

The genetic mechanism of high prolificacy in small tail han sheep by comparative proteomics of ovaries in the follicular and luteal stages

To investigate the genetic mechanism of sheep prolificacy, protein profiling of ovaries in the follicular and luteal phases was conducted. The tandem mass tag technique was used to analyze the proteomes of ovaries from STH sheep that did not have the FecB mutation in the bone morphogenetic protein receptor 1B gene. Parallel Reaction Monitoring (PRM) was operated to validate the target differentially abundant proteins (DAPs). The result showed, a total of 34,037 peptides were found, and 5074 proteins were identified. The screened DAPs strictly related to energy metabolism, hormone synthesis, ovarian function were significantly enriched in oxidative phosphorylation(COX7A, ND5, and UQCR10), ovarian steroidogenesis(StAR and HSD3B), taurine and hypotaurine metabolism(CSAD), glycosaminoglycan biosynthesis-heparin sulfate/heparin(GLCE), necroptosis(H2AX, AIFM1, and FTH1), protein digestion and absorption(COL4A1 and COL4A5) and glycosaminoglycan degradation(HYAL2 and HEXB) pathways. These analyses indicated that the reproductive performance of sheep is regulated through different pathways. In consequence, these findings are an important resource that can be used in future studies of the genetic mechanism of high fecundity traits in sheep, and these DAPs can be further investigated as candidate markers to predict prolificacy of sheep. SignificanceLitter size is an important quantitative trait, but the genetic mechanism of high-prolificacy is still unclear in sheep. Our study identified potential signaling pathways and differentially abundant proteins related to reproductive performance. These findings will facilitate a better revealing the mechanism and provide possible targets for molecular design breeding for the formation of polytocous traits in sheep.

Reproductive Performance of Sheep in Irrigated and Rainfed Areas in Krishna District of Andhra Pradesh, India

Reproductive Performance of Sheep in Irrigated and Rainfed Areas in Krishna District of Andhra Pradesh, India

Association of steroid 17-alpha-hydroxylase/17,20 lyase (CYP17) single nucleotide polymorphism (SNP) 628 and dopamine receptor D2 (DRD2) SNP939 genotypes with sheep reproductive performance.

In a previous study we investigated the association between two single nucleotide polymorphism (SNP) genotypes, namely steroid 17-alpha-hydroxylase/17,20 lyase (CYP17) SNP628 and dopamine receptor D2 (DRD2) SNP939, with two temperaments (calm and nervous) in Australian Merino sheep and concluded that the DRD2 SNP939 T/T genotype combined with the CYP17 SNP628 G/G genotype is associated with a calm temperament and could be used as a potential marker for calm sheep, whereas the DRD2 SNP939C allele combined with the CYP17 SNP628 A/A genotype is associated with a nervous temperament and could be used as a potential marker for nervous sheep. In sheep, the association between temperament and reproductive performance has been determined, but the association of these two SNP genotypes with sheep reproduction has not been investigated. Therefore, using Chinese Sinkiang Merino sheep, the present study investigated the association of the two CYP17 SNP628 and DRD2 SNP939 genotypes with sheep reproductive performance. Sheep with the DRD2 SNP939 T/T genotype combined with the CYP17 SNP628 G/G genotype had a higher ovulation rate, multiple gestation rate, better maternal behaviour and lower lamb mortality. Thus, the results of this study contribute to our knowledge of the association between genotypes and reproduction in sheep, which is beneficial for sheep genetics and breeding.

English

Sheep and goats represent an important component of the farming system by providing about 12% of the value of livestock products consumed and 48% of the cash income generated at the farm level. Although diverse sheep and goats resources are found in Ethiopia, their productivity is low; the sector has not received a great deal of attention from scientists, administrators and legislators. Strategic recording and documentation of the performances of the animals in their native environment under farmer&rsquo;s condition is very essential. Current survey study was conducted in Dwaro zone, Southern Ethiopia to assess productive and reproductive performance of sheep and goat kept under framers management condition. Primary data were collected from 270 household selected randomly, while secondary data from relevant written documents. Survey result showed that ewes and does were weaned on average at age of 126.2&plusmn;1.44 and 145.5&plusmn;1.48 and 249.0&plusmn;3.10 days in order and weaning age was significantly longer in highland and midland as compared to lowland whereas ewes age at puberty does not vary significantly across agro-ecological zone but does age at puberty is significantly shorter in highland. In addition, the finding indicated that age at first lambing and kidding was 408.0&plusmn;3.32 and 393.5&plusmn;3.05 days, respectively. Age at first lambing was not significantly (p&gt;0.05) affected by agro-ecological zones while age at first kidding of does was significantly (p&lt;0.05) longer in lowland (408.6&plusmn;7.75 days) as compared to midland (385.6&plusmn;4.31 days) and highland (386.2&plusmn;0.83 days). Furthermore, survey result revealed that mean kidding and lambing interval was 269.9&plusmn;3.08 and 269.0&plusmn;2.89 days, respectively and kidding interval was significantly shorter in highland (263.5&plusmn;6.0 days) and midland (264.0&plusmn;5.89 days) relative to lowland (281.7&plusmn;3.70 days), whereas lambing interval was not affected by agro ecological differences. Furthermore, the survey pointed out that household in the study area slaughtered sheep and goat at mean age of 258.1&plusmn;4.39 and 255.6&plusmn;2.49 days in sequence. Lowland household were preferred to slaughter sheep and goat at younger age as compared to midland and highland household for both species that preferred slaughtering of sheep and goat at older age. Feed and other related management improvement and implementing strategic breed improvement is the area that need further work in the future. Key words: Age at first kidding, lambing interval, weaning age, Dawro. &nbsp

Mutation -388 C>G of NR5A1 gene affects litter size and promoter activity in sheep

The Nuclear receptor superfamily 5, group A, member 1 (NR5A1) gene encodes a nuclear receptor that regulates the transcription of genes involved in steroidogenesis, follicular development and female fertility. Little, however, is known about the relationship of this gene with reproductive performance in sheep. In this study, the transcription initiation site of Hu sheep NR5A1 gene was located 193 nucleotides (i.e., at −193 nt) before the translational start site (ATG). The core promoter region of the NR5A1 gene ranged from −696 nt to −298 nt, and a C>G mutation at −388 nt was detected in this region. Association analysis indicated ewes with the GG genotype had greater litter size at the second and third parity than those with the CC genotype (P < 0.05). The results from the luciferase assay provided evidence that the -388 G allele increased luciferase activity compared with that of the −388 C allele. Furthermore, the -388 C>G mutation lost a CpG site and gained a novel binding site for the transcription factor, SP1, and results from an overexpression experiment and methylation analysis indicated transcription factor SP1 and methylation of the -388 C>G mutation were both involved in alteration of NR5A1 transcription activity. Results of the present study revealed that the -388 C>G mutation lost a CpG site and promoted NR5A1 gene expression, which completely superimposed positive effects on NR5A1 gene transcription activity by transcription factor SP1, resulting in a fecundity increase in Hu sheep.

Influence of SRLV infections in sheep flocks on growth and reproductive performance

The aim of the study was to determine the influence of the occurrence of SRLV infections on lamb growth and reproductive performance of sheep. The study was carried out on 98 sheep flocks from mid-Eastern Poland, covering the area of Lubelskie, Świętokrzyskie and Podkarpackie provinces. The study included 6,470 mother ewes. Flocks with at least one detected case of SRLV-positive serological test were considered infected. All flocks included in the experiment were subjected to the analysis of lamb growth on the basis of their body weight achieved on the 56th day of life. Moreover, traits related to reproductive performance, such as fertility, lamb/ewe rate and lamb weaning rate, as well as the reproductive performance itself were evaluated. The observations showed that both ewes (18.98 kg) and rams (19.70 kg) achieved higher body weights in the flocks where SRLV had not been detected. In the flocks in which the presence of SRLV was detected the achieved body weight was lower by 0.93 kg and 1.26 kg, respectively. The sheep in the SRLV-infected flocks were characterized by a significantly lower fertility and higher lamb/ewe rate in comparison to other flocks. The analysis conducted for the purpose of the study showed that the presence of SRLV in a flock resulted in a worse lamb weaning rate by about 6.69 percentage points. To sum up, the flocks with detected presence of SRLV were characterized by a significantly lower fertility and greater lamb mortality rate. The presence of SLRV also had a detrimental effect on the body weight obtained on the 56th day of life, both in rams and ewes. The results of the study clearly indicate the negative influence of SRLV on the reproductive performance of sheep..

Effect of selenium-yeast feeding on amelioration of simulated heat stress and reproductive performance in Malpura ewe under semi-arid tropical environment

The present study was carried out for 35 days to assess the effect of selenium (Se)-yeast feeding on amelioration of simulated heat stress and reproductive performance of sheep. Twelve adult Malpura ewes were divided into two groups viz., G1 (n=6, control) and G2 (n=6, Se-yeast supplemented). The ewes of G2 were provided with Se at 0.3 mg/kg feed dry matter (DM) through Se-enriched yeast (Saccharomyces cerevesiea). The animals were stall fed individually with a diet consisting of 70% roughage (Cenchrus ciliaris) and 30% concentrate. All the ewes were estrus synchronized using intra-vaginal progesterone sponges+eCG protocol. To simulate heat stress, the ewes were kept inside the psychometric chamber and were exposed to different temperature at different hours of the day. Supplementation of Se-yeast had no significant effect on physiological response. Higher glucose and a lower protein level was found in the Se-yeast supplemented group under heat stress. Plasma metabolic hormone and cortisol level was higher in G1 as compared to Se-yeast supplemented ewes. Plasma glutathione peroxidase (GPx) was 10.62% higher in G2 as compared to the G1. Estrus percentage and estradiol level was higher in G2 as compared to the G1. From the findings of the present experiment, it is pertinent to conclude that the level of Se enriched yeast fed in this study have limited potential to ameliorate heat stress. However, different doses of Se could be tried in sheep to improve resilience against heat stress.

Disruption of the sheep BMPR-IB gene by CRISPR/Cas9 in in vitro-produced embryos

BMPR-IB (also known as FecB) is a key candidate gene for the genetic control of sheep reproductive performance. Loss-of-function mutations in the sheep BMPR-IB gene lead to an increase in ovulation rate and consequently larger litter size. However, the BMPR-IB gene has been identified in only a few sheep breeds. To improve sheep reproduction through modification of the BMPR-IB gene, we designed an sgRNA to target the sheep BMPR-IB gene by using the CRISPR/Cas9 system. First, we performed gene editing by injecting Cas9/sgRNA into the cytoplasm of one-cell fertilized eggs. A total of 88 embryos were assayed by T7EI digestion and Sanger sequencing. The results reported that the efficiency of gene modification was 37.5% (33/88) and increased with the developmental stage of embryo from the 2-cell stage to the blastocyst stage. Of the 33 gene editing embryos, 12 (36%, 12/33) were homozygous and 21 (64%, 21/33) were heterozygous. Moreover, sequence analysis of the PCR products from the positive embryos revealed that there were more than 10 modification forms that resulted in frame shift and truncated proteins. Further analysis by cloning and sequencing of each individual embryo showed a high level of mosaicism. In addition, off-target event analysis revealed that none of the off-target mutations was introduced into the embryos. Our results indicated that the Cas9/sgRNA system is a simple and efficient tool that may potentially be used in the genetic modification of the sheep BMPR-IB gene in vivo.

Appetitive and Consummatory Sexual Behaviors of Rams Treated with Exogenous Testosterone and Exposed to Anestrus Dorper Ewes: Efficacy of the Male Effect.

We determine whether Dorper rams treated with testosterone in the sexual resting season trigger both appetitive and consummatory sexual behaviors and sexual and reproductive outcomes in anestrous ewes at 26° North during March-April. Dorper rams (n=12, 2.5years) were randomly divided prior to mating in two groups: GT (treated group; n=6), treated with testosterone propionate (25mg i.m. every 3days×3weeks) and GC (control group; n=6), treated with saline. Thereafter, adult anovulatory Dorper ewes (n=61) were exposed to the GT-rams while the other group (n=60) was exposed to the GC-rams. Ram's appetitive sexual behavior was similar (50%) in both groups, yet the GT-rams exerted 100% of the consummatory sexual behavior. Sexual and reproductive outcomes of the anestrus females exposed to both male groups considered two phases: 0-15 and 16-25days from exposure to males. Involved variables were: ewes in estrus, ewes ovulating, duration of estrus, pregnant ewes, and lambed ewes. All the average variables favored those ewes exposed to GT-males: ewes in estrus: 85 versus 40%; ewes ovulating: 80 versus 53%; duration of estrus: 37 versus 25h; pregnant ewes: 60 versus 31%, and lambed ewes: 57 versus 31%. Results confirm that adult Dorper rams treated with exogenous testosterone had improved consummatory sexual behavior and induced increased ovulation and pregnancy rates when exposed to anestrus ewes. This feasible and inexpensive testosterone-based protocol through the male effect also enhanced both sexual and reproductive outcomes in previously anestrous Dorper ewes during the natural out-of-season. Results are important to speed up reproductive performance of sheep during the natural anestrous season at this latitude, while also they embrace interesting outcomes from a comparative sexual behavior stand point.

A review on prolificacy genes in sheep.

Ovulation rate and litter size are important reproduction traits in sheep and are of high economic value. Reproduction traits typically have low to medium heritabilities and do not exhibit a noticeable response to phenotypic selection. Therefore, inclusion of genetic information of the genes associated with reproductive ability could efficiently enhance the selection response. The most important major genes affecting prolificacy and their genetic diversities in different sheep breeds were reviewed. Different causative mutations with major effects on reproductive traits including ovulation rate and litter size have been found in various sheep breeds around the world. A general overview of the studies on main prolificacy genes showed that some alleles may express different phenotypic effects in different breeds, and thus, further studies on epistatic effects are necessary for more understanding of genetic control of reproductivity in sheep. Regarding the polygenic control of fertility traits, application of new high-throughput technologies to find new variants is essential for future studies. Moreover, genomewide association studies and genomic best linear unbiased predictions of breeding values are likely to be effective tools for genetic improvement of sheep reproductive performance traits.

Effect of Feeding Longan Dimocarpus longan Residue before Estrus Synchronization on Reproductive Performance in Ewes

To evaluate the effect of feeding longan residue (longan fruit; grade C) before estrus synchronization on reproductive performance in sheep, sixteen ewes observed in estrus were selected and randomly assigned to 2 groups: control group (n=8) received the maintenance diet whiles the longan-supplemented group (n=8) received the maintenance diet plus 300 g DM/head/day of longan fruit for 17 days. Blood concentrations of glucose, insulin, progesterone (P4), and estradiol (E2), and follicular population were recorded. After the nutritional treatments, all ewes were synchronized for estrus with controlled intravaginal drug release (CIDR) devices and 400 IU pregnant mare serum gonadotropin. Ewes exhibiting estrus were subjected to assisted natural mating by rams. Ewes fed longan-supplemented diet had greater feed intake than ewes fed the control diet. Glucose concentrations were higher in longan-supplemented than those in control ewes on days 7, 14, and 17. Insulin concentrations were only higher in longan-supplemented group than those in control group on day 17. The longan-supplemented ewes had higher E2 concentrations than non-supplemented ewes on days 14 and 17. On days 14 and 17, numbers of total follicles had significantly greater in longan-supplemented ewes compared with control ewes. Estrous response and conception rate were not different between control and treatment ewes. It was concluded that the 17 days of dietary supplementation stimulate ovary (total follicles) ready to respond to the synchronization of estrus. However, dietary supplementation with longan fruit in ewes prior to the start of the estrus synchronization did not enhance reproductive performance.

The influence of separation distance during the preconditioning period of the male effect approach on reproductive performance in sheep

The study was aimed to test the effect of the separation distance between males and females during the preconditioning period on the reproductive performance of Santa Inês ewes after the male effect. Santa Inês ewes were kept at distances of 3000 m (T1), 3 m (T2), and 300 m (T3) from rams for 60 days before starting 45-day mating seasons during the dry period (DP) and rainy periods (RP). Mating events were observed daily at 6:00 h and 16:00 h by trained personnel for one hour intervals. Estrous were scored as synchronized when observed until day 5 after breeding season start. Pregnancy diagnosis was performed by ultrasonography. In the DP, the first estrous averaged at 15.45±10.36 (T1), 9.25±6.41 (T2) and 13.05±10.24 (T3) days and in RP was 8.73±5.84 (T1), 9.30±5.62 (T2) and 6.10±5.66 (T3) days. All females cycled during both DP and RP. Estrous synchronization occurred in 20% of the females during DP (T1: 30%, T2: 15%, and T3: 15%). In the RP, estrous synchronization occurred in 40% of all females (T1: 30%, T2: 35%, and T3: 45%). The pregnancy rates in DP and RP were T1: 85%, T2: 80%, and T3: 75%. The results show that the male effect can be obtained simply by avoiding physical contact between males and females throughout the year under tropical conditions.

Effect of a Middle-Term Flushing in Chilota and Suffolk Down Sheep Breeds in Chilo&#233; Archipelago

In Chiloe Archipelago, traditional and short-term flushing are not usually feasible for small-scale sheep farms due to economic and logistic reasons, and cheaper/easier alternatives are needed. The effects of flushing on the reproductive performance of sheep can vary depending on the breed; nevertheless, this effect has never been compared between Chilota and other breeds in Chiloe. The objective of this study was to assess the effect of the application of a middle-term flushing in fertility, prolificacy and lamb mortality in two sheep breeds in Chiloe archipelago, Chile. Under the conditions of this study, the supplementation (300g of concentrate per sheep per day) for ten days before and after the introduction of the ram in the flock was an efficient tool to improve the fertility and prolificacy on Chilota and Suffolk Down ewes, becoming an alternative to traditional and short-term flushing in low technology sheep farms in Chiloe Archipelago.

The influence of separation distance during the preconditioning period of the male effect approach on reproductive performance in sheep

The study was aimed to test the effect of the separation distance between males and females during the preconditioning period on the reproductive performance of Santa Inês ewes after the male effect. Santa Inês ewes were kept at distances of 3000 m (T1), 3 m (T2), and 300 m (T3) from rams for 60 days before starting 45-day mating seasons during the dry period (DP) and rainy periods (RP). Mating events were observed daily at 6:00 h and 16:00 h by trained personnel for one hour intervals. Estrous were scored as synchronized when observed until day 5 after breeding season start. Pregnancy diagnosis was performed by ultrasonography. In the DP, the first estrous averaged at 15.45±10.36 (T1), 9.25±6.41 (T2) and 13.05±10.24 (T3) days and in RP was 8.73±5.84 (T1), 9.30±5.62 (T2) and 6.10±5.66 (T3) days. All females cycled during both DP and RP. Estrous synchronization occurred in 20% of the females during DP (T1: 30%, T2: 15%, and T3: 15%). In the RP, estrous synchronization occurred in 40% of all females (T1: 30%, T2: 35%, and T3: 45%). The pregnancy rates in DP and RP were T1: 85%, T2: 80%, and T3: 75%. The results show that the male effect can be obtained simply by avoiding physical contact between males and females throughout the year under tropical conditions.

Sheep Reproductive Performance and Lamb Survivability under Mature Oil Palm

The study examines the seasonal reproductive performance of sheep reared under oil palm plantation and the subsequent survival of lambs up to weaning age. On-station studies were carried out from 2007 to 2010 at CSIR-Oil Palm Research Institute, Kusi (001.45 W, 0600 N and 150 m above sea level). The average total rainfall is about 1600 mm/annum with average daily maximum temperature of 32±2°C. Sheep productivity (% lambing, litter size per ewe, survival rate, monthly birth and death rates) were the variables measured. An annual average of 58 ewes and 4 lambs were used. Results show that while lambing rate was 98%, lamb survival was 63.84%. This implies that almost two-fifth of yearly reproduction was lost to mortality with significantly large number of lambs dying in August. Though there was high percentage of lambing, this was offset by high mortality of lambs.