Fertility Of Ewes Research Articles

Dietary n-3 PUFA augments pre-ovulatory follicle turnover and prolificacy in well-fed ewes

The present study evaluated the effect of dietary supplementation with n-3 polyunsaturated fatty acids (PUFA) on preovulatory follicle (POF) turnover, prolificacy, and endocrine and metabolic milieu in Malpura sheep. Fifty cyclic ewes with 3–3.5 body condition scores on a five-point scale were allocated equally to two groups (n = 25) following estrus synchronization and were supplemented with 0.6 mL/kg body weight of n-3 PUFA-rich fish oil (FO) or palm oil (PO) as control, for 60 d following an acclimatization period of 7 d. All ewes were mated with sexually active rams at the end of the supplementation period. On ultrasonographic ovarian scanning at the last fourth estrus, the mean number of POFs was 77.8% greater (P < 0.01) in FO ewes than in the PO ewes. The proportion of ewes with multiple ovulations two months after the beginning of supplementation was 56% in the FO group as compared to 8% in the PO group. The number of fetuses was 46% higher (P < 0.01) in the FO than in the PO ewes at d 45 of gestation. At lambing, the twinning percent in the FO ewes was three times greater than in the PO ewes (27.3 vs. 9.1%). Plasma cholesterol, estradiol, and insulin concentrations were lower (P < 0.01) in ewes fed with FO than those offered PO group at the end of the feeding period. It was concluded that the dietary supplementation of n-3 PUFA-rich FO in well-fed Malpura ewes improved the number of follicles and ovulation rate which led to an increased prolificacy, accompanied by a reduction of plasma cholesterols, estradiol, and insulin.

Comparison between the CIDR or sponge with hormone injection to induce estrus synchronization for twining and sex preselection in Naimi sheep

Abstract The management of sheep reproduction requires the induction and synchronization of the estrus cycle and ovulation for the ewe out-of-season and/or synchronized lambing. These managements are based on the insertion of an intravaginal device of controlled internal drug release (CIDR or sponge) and then the administration of a hormonal injection, such as PMSG, eCG, hCG, or GnRH. This study aimed to compare the impact of CIDR or sponges, with PMSG and GnRH injection, respectively, for inducing estrus synchronization, lambing rate, twining, and sex preselection rate in Naimi sheep. A total of 86 Naimi sheep ewes and six male rams with proven fertility were used in this study. The results showed that the first ewes or CIDR group had the highest ewe fertility rate of 26/28 (92.59%) with a 35/92 (38.04%) lamb production ratio. The offspring sex ratio was 22/35 males (62.85%) and 13/35 female lambs (37.14%). Their twin ratios were 9/22 (34.4%), producing 14 males (77.77%) and 13 females (37.14%). The second or sponge ewe group’s fertility ratio was 16/26 (61.53%). They sired the lowest offspring ratio of 20/92 total lambs (21.73%) and had sex ratios of 11/20 males (55.0%) and 9/20 (45.0%) female lambs. The twin production ratios were 4/22 (25% with two males and two males with female twins). Their twin sex ratio was six males (77.77%) and two females (22.34%). The third or control ewe group’s fertility rate was 29/33 (87.87%). They produced 37/92 (40.27%) lambs, and the total sex ratios were 22/37 male lambs (59.45%) and 15/35 (40.45%) female lambs. They produced eight twins (27.58%), and their twins’ sex was equal to six male and six female (50%) lambs. Regarding the progesterone and testosterone hormone levels, no differences during pre- or post-intravaginal insertion were observed, but the estrogen level showed some differences during pre-insertion. In conclusion, the use of CIDR with hormone injection is better for reproduction management, male lambing, and sex preselection rate. The control group produced approximately the same fertility rate with equal male and female lambing sex preselection rates.

ВПЛИВ ЗГОДОВУВАННЯ ДОБАВКИ ЗООФІТОПЛАНКТОНУ НА ОБМІН РЕЧОВИН І ВІДТВОРНІ ПОКАЗНИКИ ОВЕЦЬ ПОРОДИ ЛАКОН

Продуктивні якості овець залежать від породності, годівлі й утримання, віку тварини, місяця лактації, кількості ягнят, яких вигодовує вівцематка. Вирішення цієї проблеми можливе лише за умови розведення та утримання тварин. Своєю чергою головною ланкою утримання тварин є їх повноцінна годівля. На сьогодні загальний рівень годівлі низький, а її повноцінність не відповідає вимогам. Важливим резервом поповнення потреби у високобілкових кормах, кормовому протеїні та біологічно активних речовинах у наш час можуть бути флора й фауна водоймищ. Вивчали показники відтворних властивостей вівцематок та обміну речовин за умови включення в раціон комбікорму з вмістом у його складі протеїново-мінеральної добавки з аквакультури річки Дністер. Дослідження ґрунтується на проведенні науково-господарського досліду на вівцематках молочно-м’ясної породи лакон за місяць до парування та дає змогу стверджувати, що згодовування протеїново-мінеральної добавки з аквакультури в раціонах вівцематок дослідних груп сприяло заплідненості маток під час першого осіменіння. Результати досліджень вказують на те, що жива маса маток у різні періоди досліду змінювалася. Встановлено, що за період підготовки до осіменіння жива маса маток контрольної групи збільшилася на 3,11 кг, а першої та другої дослідних груп – на 3,67 кг і 3,94 кг відповідно, що більше за контрольну групу тварин на 18% (Р&lt;0,05) і 26,6% (Р&lt;0,01). Унаслідок дослідження встановлено, що жива маса маток контрольної групи за період лактації зменшилася на 9,0 кг, або 11,79%; маса маток першої дослідної групи – на 7,27 кг, або 8,9%; маса маток другої дослідної групи – на 5,5 кг, або 7,57%; маса маток третьої дослідної групи – на 8,24 кг, або 11,5%. Встановлено можливість і доцільність введення в комбікорми вівцематок породи лакон 3–12% протеїново-мінеральної добавки з аквакультури річки Дністер замість ячменю. За комплексною оцінкою найвища ефективність спостережена за доз ПМДА в комбікормі маток у межах 7% за масою комбікорму.

INFLUENCIA DE LA PRESINCRONIZACIÓN DEL ESTRO EN VARIABLES REPRODUCTIVAS DE OVEJAS DE LA RAZA KATAHDIN PORTADORAS DEL GEN GDF9

&lt;p&gt;&lt;strong&gt;Background&lt;/strong&gt;: Genetic improvement in the sheep species focuses on increasing the number of offspring per sheep. Heritable characteristics such as ovulation rate, fertility, and prolificacy are desirable. &lt;strong&gt;Objective&lt;/strong&gt;: To evaluate the influence of estrus pre-synchronization with PGF2α on the manifestation of estrus, onset and return to estrus (1st and 2nd), pregnancy, lambing, prolificacy, and fertility in Katahdin ewes carrying exon 2 of the gene Factor Growth and Differentiation 9 (&lt;em&gt;GDF9&lt;/em&gt;). &lt;strong&gt;Methodology&lt;/strong&gt;: Seventy-two ewes were randomized into four treatments (T): T1 (n = 18), ewes without &lt;em&gt;GDF9&lt;/em&gt; gene and without estrus pre-synchronization; T2 (n = 17), ewes without &lt;em&gt;GDF9&lt;/em&gt; gene and with estrus pre-synchronization; T3 (n = 19) ewes with the &lt;em&gt;GDF9&lt;/em&gt; gene and without estrus pre-synchronization, and T4 (n = 18), ewes with the &lt;em&gt;GDF9&lt;/em&gt; gene and with estrus pre-synchronization. &lt;strong&gt;Results&lt;/strong&gt;: The presence of estrus, the onset of estrus, and returns to estrus, pregnancy, and lambing percentages were not different between treatments (p&amp;gt;0.05). The average pregnancy and lambing in both cases were 86.2% and the average general prolificacy was 1.4 lambs per ewe for all four treatments. There were also no significant differences for the prolificacy or fertility rate (p&amp;gt;0.05). &lt;strong&gt;Implications&lt;/strong&gt;: The present study contributes to the understanding of the use of presynchronization with PGF2α and the effect of the presence of exon 2 of the &lt;em&gt;GDF9&lt;/em&gt; gene on reproductive variables. &lt;strong&gt;Conclusions&lt;/strong&gt;: The presynchronization of estrus with PGF2α and the presence of exon 2 of the &lt;em&gt;GDF9 &lt;/em&gt;gene in ewes of the Katahdin breed did not have a significant effect on the reproductive variables evaluated.&lt;/p&gt;

Comparison of estrus response and subsequent fertility following estrus synchronization with six protocols in Ossimi ewes during the early summer season

This study investigates the effect of estrus synchronization on the reproductive performance of Ossimi ewes during the early summer season to prove that they are cyclic throughout the year in subtropical climates. In June, 280 ewes were assigned to seven (n = 40) groups and received one of the following: 1) short-term progesterone (ST) P4 treated ewes received 20 mg P4 day after day for 6 days and 500 international unit (IU) equine chorionic gonadotropin (eCG) on day 6; 2) long-term P4 (LT) P4 treated ewes received 20 mg P4 day after day for 12 days and 500 IU eCG on day 12; 3) double prostaglandin (PG) F2α 7days apart and 500 IU eCG on day 7 (PGF2α-7d); 4) double PGF2α 14 days apart and 500 IU eCG on day 14 (PGF2α-14d); 5) traditional ovulation synchronization (T-Ovsynch; gonadotropin-releasing hormone (GnRH)-0 day; PGF2α-5 day and GnRH-7 day); 6) non-traditional ovulation synchronization (NT-Ovsynch; GnRH-0 day; PGF2α-7 day and GnRH-9 day); 7) control ewes received no treatment. There were significant differences among groups for estrus rate, the onset of estrus, pregnancy, and lambing rates as well as prolificacy and gestation period. The highest (90 %) estrus rate was recorded in (LT) P4, PGF2α-14d, and NT-Ovsynch protocols while the lambing rate was the maximum (100 %) in PGF2α-14d. Although all treatments had a positive effect on ewe fertility; long-term protocols particularly PGF2α-14d; are recommended to improve Ossimi ewe fertility during the early summer season.

Effects of the central melanocortin system on feed intake, metabolic hormones and insulin action in the sheep.

Voluntary feed intake is insufficient to meet the nutrient demands associated with late pregnancy in prolific ewes and early lactation in high-yielding dairy cows. Under these conditions, peripheral signals such as growth hormone and ceramides trigger adaptations aimed at preserving metabolic well-being. Recent work in rodents has shown that the central nervous system-melanocortin (CNS-MC) system, consisting of alpha-melanocyte-stimulating hormone (α-MSH) and agouti-related peptide (AGRP) acting respectively as agonist and antagonist on central MC receptors, contributes to the regulation of some of the same adaptations. To assess the effects of the CNC-MC on peripheral adaptations in ruminants, ewes were implanted with an intracerebroventricular cannula in the third ventricle and infused over days with artificial cerebrospinal fluid (aCSF), the α-MSH analog melanotan-I (MTI), or AGRP. Infusion of MTI at 0.03 nmol/h reduced intake, expressed as a fold of maintenance energy requirement (M), from 1.8 to 1.1 M (P < 0.0001), whereas AGRP at 0.3 nmol/h increased intake from 1.8 to 2.0 M (P < 0.01); these doses were used in all subsequent experiments. To assess the effect of MTI on plasma variables, sheep were fed ad libitum and infused with aCSF or MTI or pair-fed to MTI-treated sheep and infused with aCSF (aCSFPF). Feed intake of the MTI and aCSFPF groups was 40% lower than the aCSF group (P < 0.0001). MTI increased plasma triiodothyronine and thyroxine in an intake-independent manner (P < 0.05 or less) but was devoid of effects on plasma glucose, insulin, and cortisol. None of these variables were altered by AGRP infusion in sheep fed at a fixed intake of 1.6 M. To assess the effect of CNS-MC activation on insulin action, ewes were infused with aCSF or MTI over the last 3 d of a 14-d period when energy intake was limited to 0.3 M and studied under basal conditions and during hyperinsulinemic-euglycemic clamps. MTI had no effect on plasma glucose, plasma insulin, or glucose entry rate under basal conditions but blunted the ability of insulin to inhibit endogenous glucose production during hyperinsulinemic-euglycemic clamps (P < 0.0001). Finally, MTI tended to reduce plasma leptin in sheep fed at 0.3 M (P < 0.08), and this effect became significant at 0.6 M (P < 0.05); MTI had no effect on plasma adiponectin irrespective of feeding level. These data suggest a role for the CNC-MC in regulating metabolic efficiency and peripheral insulin action.

Synchronization of estrus using progesterone injections followed by human menopausal gonadotropin in ewes.

Serial progesterone injections followed by human menopausal gonadotropin (hMG), instead of equine chorionic gonadotropin (eCG), were used to synchronize estrus in ewes. Shal ewes (n = 189) were assigned into five groups and each group was divided into two sub-groups to receive gonadotropins including eCG (300 IU; intra-muscular) or hMG (one ampoule; subcutaneously, SC). All ewes received prostaglandin (PG) F2α six days after introducing ram (day 0). Ewes received 0 (control), one, two, three or four injections of progesterone (50.00 mg; SC), 72 hr apart. The first progesterone was injected at the time of PG injection. Ewes in treatment groups received gonadotropins 48 hr after the last progesterone injection. Control group ewes received gonadotropins, at the time of PG injection. Mating was recorded after introducing fertile rams. Data were analyzed using GLM and GENMOD procedures in SAS. The incidence of estrus was less in control and ewes received a single progesterone (34.20%) compared to ewes received two (64.10%), three (81.10%) and four injections (68.40%) of progesterone. Time to estrus was earlier in control (45.70 ± 4.41 hr) than progesterone-treated groups (63.60 ± 1.79 hr). Fertility (51.30%) and fecundity (78.40%) of ewes received three progesterone injections were significantly greater than other progesterone-treated groups. There was no significant difference in reproductive indices between eCG and hMG sub-groups. In conclusion, during the non-breeding season, three injections of progesterone, three days apart, starting six days after ram exposure, in association with hMG, 48 hr after the last progesterone injection, could provide a sound reproductive performance in Shal ewes.

Effects of selenium, vitamin E, and β-carotene administration on fertility of Awassi ewes synchronized for estrus in non-breeding season

The aim of this study was to evaluate the effect of selenium, β-carotene, and vitamin E administration on fertility of Awassi ewes synchronized in non-breeding season. A total of 80 multiparous Awassi ewes, aged 2 to 6 years were enrolled in the study. Intravaginal sponges containing flugeston acetate (20 mg cronolon) was inserted into vagina and allowed to remain in vagina for nine days. Ewes were randomly divided into two groups. Group I received intramuscular injections of 1 mg sodium selenite, 60 mg vitamin E, 75 mg β-carotene, and 100 mg DL-α-tocopherol acetate at sponge insertion, sponge removal, and 18 days after the introduction of ram. Group II remained as control group and received no treatment. On the removal of the sponges, 500 IU eCG and 0.075 mg D-cloprostenol were injected intramuscularly. Ram was introduced for 1 hr twice a day 24 hours after the sponge removal. Interval between sponge removal and estrus, estrus rates, conception rates, pregnancy rates, lambing rates, and fecundity rates in group I and group II were 45.30±1.71 and 43.94±1.72 hours, 79.1% and 86.6%, 66.66% and 72.41%, 54.05% and 58.33%, 100% and 100%, and 135% and 138%, respectively. There were no statistical differences between the groups (p&gt;0.05). In conclusion, the administration of Se, β-carotene, and vitamin E in estrus synchronization protocols in non-breeding season had no positive effect on the fertility characteristics of Awassi sheep.

Effect of flaxseed oil dosing on fertility, growth characteristics and some physical, biochemical, and hormonal blood parameters during the early pregnancy of Awassi ewes.

This study aims to complete the direction of experimental research in determining the effect of flaxseed oil doses on the fertility of Awassi ewes, as well as some important blood parameters to clarify the animal's physiological state during the duration of the experiment. This study was conducted in the animal field (College of Agriculture - Tikrit University) for 76 days (16 days before and 60 days after fertilization). 2-3 years have an average live weight of 51.74 kg, and the ewes were randomly divided into three treatments (each treatment was nine ewes). The three treatments were given doses of flaxseed oil at the rate of 0, 6 and 8% / kg of feed, respectively. The results showed that there was no significant difference (P≤0.05) between the treatments in the ewes' weights and physical blood characteristics during the experiment period, while it was noted that the fertility rate of the second and third treatments amounted to 66.66% for each of them, over the first treatment (55.55%). In addition, the second treatment was significantly (P≤0.05) superior in blood globulin concentration over the rest. In contrast, the third treatment was significantly (P≤0.05) superior in triglyceride concentration (62.66) mg/dL, and the first treatment showed a significant (P≤0.05) superiority. In glucose concentration (70.33) mg/dL. The following characteristics were not significantly different in total protein, albumin, urea, creatinine, ALT and AST enzymes, as well as no significant difference between treatments in the concentration of estrogen and progesterone hormones. Keywords: flaxseed oil, Awassi ewes, fertility

Effect of Culture Medium on in vitro Fertilization in Local Iraqi Ewes.

in vitro fertilization (IVF) is considered to be the most important reproductive biotechnological method having great potential to accelerate genetic improvement in ruminants as well as for research on embryonic development. The present study aimed to investigate the effect of culture medium and the addition of natural and synthetic antioxidants on in vitro maturation (IVM), fertilization (IVF), and culture (IVC) in local Iraqi ewes. A total of 304 reproductive systems of local ewes were collected from a slaughterhouse in Fallujah, Anbar Province, Iraq from 3, January to 1, July 2021. The study was conducted in the Reproductive Biotechnology Laboratory, Department of Surgery and Theriogenology, College of Veterinary Medicine, University of Fallujah, Iraq. A total of 1368 oocytes were recovered from 608 ovaries surrounded by cumulus cells. The method of collection was aspiration and oocytes were divided into eight treatments. The first (T1), the second (T2), the third (T3), the fourth (T4), the fifth (T5), the sixth (T6), the seventh (T7), and the eighth (T8) treatments were MEM + Capparis spinosa extract 50µmol, MEM + Silymarin extract 100µmol, MEM + Coenzyme Q10 5 µmol, MEM only serves as a control, DMEM + Capparis spinosa extract 50 µmol, DMEM + Silymarin extract 100µmol, DMEM + Coenzyme Q10 5µmol and DMEM only serves as a control, respectively. The results indicated a significant difference (P≤0.05) between T5 (DMEM + Capparis spinosa extract) and other controls or treatments. Cultural medium DMEM with Capparis spinosa extract (as an antioxidant) presents the best results in the morula and blastocyst stage.

Impact of breeding for reduced methane emissions in New Zealand sheep on maternal and health traits.

Enteric methane emissions from ruminants account for ∼35% of New Zealand’s greenhouse gas emissions. This poses a significant threat to the pastoral sector. Breeding has been shown to successfully lower methane emissions, and genomic prediction for lowered methane emissions has been introduced at the national level. The long-term genetic impacts of including low methane in ruminant breeding programs, however, are unknown. The success of the New Zealand sheep industry is currently heavily reliant on the prolificacy, fecundity and survival of adult ewes. The objective of this study was to determine genetic and phenotypic correlations between adult maternal ewe traits (live weight, body condition score, number of lambs born, litter survival to weaning, pregnancy scanning and fleece weight), faecal and Nematodirus egg counts and measures of methane in respiration chambers. More than 9,000 records for methane from over 2,200 sheep measured in respiration chambers were collected over 10 years. Sheep were fed on a restricted diet calculated as approximately twice the maintenance. Methane measures were converted to absolute daily emissions of methane measured in g per day (CH4/day). Two measures of methane yield were recorded: the ratio of CH4 to dry matter intake (g CH4/kg DMI; CH4/DMI) and the ratio of CH4 to total gas emissions (CH4/(CH4 + CO2)). Ewes were maintained in the flocks for at least two parities. Non-methane trait data from over 8,000 female relatives were collated to estimate genetic correlations. Results suggest that breeding for low CH4/DMI is unlikely to negatively affect faecal egg counts, adult ewe fertility and litter survival traits, with no evidence for significant genetic correlations. Fleece weight was unfavourably (favourably) correlated with CH4/DMI (rg = −0.21 ± 0.09). Live weight (rg = 0.3 ± 0.1) and body condition score (rg = 0.2 ± 0.1) were positively correlated with methane yield. Comparing the two estimates of methane yield, CH4/DMI had lower heritability and repeatability. However, correlations of both measures with adult ewe traits were similar. This suggests that breeding is a suitable mitigation strategy for lowering methane yield, but wool, live weight and fat deposition traits may be affected over time and should be monitored.

Integrated transcriptome and regulatory network analyses identify candidate genes and pathways modulating ewe fertility

Fertility in ewes is closely linked to ovulation rate and can be predicted by transcriptome profiling to identify candidate genes, biomarkers, and underlying molecular mechanisms. Our objective was to explore the genetic basis of ewe fertility by combining RNA-Seq data analyses of ovarian tissues from high and low fertility ewes with published transcriptome studies (i.e., literature mining). Integration of these 2 sources identified 113 differentially expressed genes (DEGs) associated with ewe fertility. Among these, 21 genes (CTNNB1, BMPR1B, BMP2, GDF9, BMP15, FSHR, TGFBR2, C-MET, KIT, MMP9, FST, LHCGR, SPP1, CYP19, CTSS, C1QB, FGF1, FGF18, BMP7, INHBA, and PAX8) were identified as hub (highly connected) genes for ewe fertility and were subjected to protein-protein interaction (PPI) network, mRNA-miRNA regulatory bipartite network, and subnets construction. Gene ontology (GO) terms enrichment analysis of the DEG represented 28, 23, and 21 GO terms associated with ewe fertility in categories of biological process, molecular functions, and cellular components, respectively. Based on annotation results, DEGs have major roles in signaling pathways related to cytokine-cytokine receptor interactions, ovarian steroidogenesis, and the TGF-beta, MAPK, Hippo, PI3K-Akt, Rap1, and Ras signaling pathways. Identification of these genes, metabolic and signaling pathways, and their related functions, could provide new insights into biological mechanisms of transcriptome profiling in the ovary and inform future studies of biomarkers for ewe fertility.

Efficiency of royal Jelly on in vitro fertilization in local Iraqi ewes

This study was designed to investigate the effect of addition several concentrations of royal jelly to the media used in the in vitro maturation process of Iraqi sheep. The ovary was brought from the Al-Shulla slaughterhouse and transferred to the obstetric laboratory at the College of Veterinary Medicine at the University of Baghdad by a thermal insulating box containing the physiological solution with the antibiotic penicillin at a temperature of 30-38°C. In the laboratory, the ovaries were washed with a neutral buffer solution and then the oocytes were collected by two different methods slicing ovaryor follicle aspiration. The oocytes were classification into four groups depending on the layers of the cumulus cells surrounding the oocytes, as well as the homogenous of the cytoplasm. Oocytes that are completely or partially surrounded by cumulus cells and homogeneous cytoplasm considered normal oocytes but the oocytes denuded from the cumulus cells and heterogeneous cytoplasm considered abnormal oocytes was discarded. Normal oocytes were divided randomly into four groups at maturation; the first group was matured by TCM media alone and was considered as a control group.

Efficiency of Artificial Insemination at Natural Estrus in Organic Churra Ewes.

Simple SummaryHormonal treatments used to synchronize estrus in sheep artificial insemination procedures can cause several physiological problems that can affect negatively fertility and animal health; however, alternative protocols based on the detection of natural estrus offer a more sustainable option while reaching successful fertility results. Therefore, in this study, an artificial insemination protocol at natural estrus in organic Churra sheep was performed. In the protocol design phase, 125 ewes were exocervically inseminated, and their fertility was assessed based on the number of inseminations, physiological state, body condition, estrus detection–insemination interval and vaginal fluids in cervix. That protocol was repeated in six consecutive years. In all ewes, fertilities based on the timing of insemination after estrus detection were very high. Lactating ewes produced better results than did dry ewes, which was probably because of the better feeding of the former. In addition, double insemination increased the fertility of ewes, whose estrus was detected within 16 h of onset. Body condition and amount of vaginal fluid were correlated with fertility. In conclusion, exocervical inseminations at natural estrus can produce acceptable fertility and prolificity in Churra ewes, avoiding physiological problems derived from the use of hormonal treatments.Hormonal treatments used in the artificial insemination (AI) of sheep can cause several physiological problems that can affect negatively fertility and animal health; however, AI protocols based on the detection of natural estrus offer a more sustainable option and can achieve high fertility. In this study, an AI protocol at natural estrus in organic Churra sheep was performed. In the first phase (AI protocol development), 125 ewes were exocervically inseminated, and their fertility was assessed based on the following factors: number of AI, physiological state, body condition, estrus detection–AI interval, and vaginal fluids in cervix. That protocol was repeated for six consecutive years. In all individuals, fertilities based on the timing of insemination after estrus detection were very high. Lactating ewes produced better results than did dry ewes, which was probably because of the better feeding of the former. In addition, double insemination increased the fertility of ewes whose estrus was detected within 16 h of onset. Body condition and amount of vaginal fluid were correlated with fertility. Exocervical inseminations at natural estrus can produce acceptable fertility and prolificity in Churra ewes.

176 Are Ovarian Reserve Parameters Related to Reproductive Tract Development and Fertility in Ewes?

Abstract There are differences between cows and ewes in ovarian reserve parameters. No major genes influencing follicle numbers have been identified in cows, whereas several genes have variants reported to influence follicle numbers in ewes. In contrast, antral follicle count is associated with fertility in cows, and we reported that beef cows that failed to conceive in 2 consecutive years had fewer antral follicles and smaller reproductive tracts than cows that had never failed to conceive. In the current study, we tested the hypothesis that ewes that had failed to lamb (BARREN) in 4 consecutive annual breeding seasons of 21– 35 d with rams that had passed a breeding soundness exam have fewer follicles and smaller reproductive tracts than ewes that consistently produced lambs (FERTILE) under the same breeding protocols. BARREN ewes (n = 19) were paired by breed, age, and sire to a FERTILE control ewe (n = 19) and reproductive tracts were recovered at necropsy. All visible antral follicles in both ovaries were counted and a representative cross section of one ovary was embedded for histological evaluation of primordial follicle numbers. The reproductive tract was weighed, and ovulatory status was evaluated. Paired t-tests indicated that BARREN ewes had 25.6 ± 5.0 fewer antral follicles per pair of ovaries, 17.3 ± 4.4 fewer primordial follicles per histological section, and 54.5 ± 18.7 g lighter reproductive tracts than FERTILE ewes (P ≤ 0.01). The odds of FERTILE ewes being ovulatory at necropsy were 2.25 that of BARREN ewes, but this did not differ from expectation by McNemar’s test (P = 0.13). The results indicate that size of the ovarian reserve influences fertility in ewes as it does in cows. USDA is an equal opportunity provider and employer.

The efficacy of intravaginal antibiotic or their combination with different gonadotropins on vaginitis and fertility in ewes synchronized with progesterone impregnated intravaginal sponges

This study was conducted with two experiments to investigate the efficacy of intravaginal antibiotic or their combination with different gonadotropin use on vaginitis and the fertility in Berrichon ewes. All ewes (n = 106) were synchronized with intravaginal sponges containing 60 mg medroxyprogesterone acetate for 14 days. For the first experiment, ewes (n = 50) received 50 mg enrofloxacin (TRT) to sponge prior to insertion or received no treatment to sponge (CON) during nonbreeding season. For the second experiment, ewes (n = 56) were randomly assigned to one of the four groups (TRT-E; TRT-G; CON-E; CON-G) according to the presence of antibioterapy (TRT or CON) to sponge and variety of gonadotropins at sponge withdrawal (equine chorionic gonadotropin-eCG; E, 500 IU) or 24 h later after sponge withdrawal (gonadotropin-releasing hormone-GnRH; G, 10 ?g) during breeding season. Vaginitis and odour were scored according to amount/aspect and odour of discharge. The addition of enrofloxacin did not change the vaginitis score (0.65 ± 0.52 vs. 0.79 ± 0.67, p = 0.25) and vaginal discharge odour score (2.07 ± 0.71 vs. 2.25 ± 0.84, p = 0.26) in both experiments. Oestrus response and pregnancy rate were 88%; 56% for TRT and 80%; 40% for CON in the first experiment (p > 0.05). These parameters were 92.3%; 69.2% for TRT-E, 86.7%; 53.3% for CON-E, 71.4%; 7.1% for TRT-G, and 64.3%; 21.4% for CON-G group. The pregnancy rate was higher (p = 0.002) in TRT-E group than TRT-G and CON-G. Additionally, oestrus response (p = 0.05) and pregnancy rate (p = 0.0001) were higher in eCG group (89.2%; 60.7%) than GnRH group (67.8%; 14.3%) in the second experiment. In conclusion, local antibiotherapy with enrofloxacin did not alter vaginitis score and fertility. However, GnRH reduced the oestrus response and pregnancy rate compared to eCG.

Validation Study of c.746A&gt;G SNP of BMPR1B Gene Associated with Litter Size in Sheep Genetic Resources of Bangladesh

The BMPR1B gene is one of the major fecundity genes that have been investigated in different sheep populations worldwide for its association with prolificacy traits. The present study was performed to validate the association of c.746A&gt;G SNP of BMPR1B gene with litter size trait in different sheep populations of Bangladesh. A total of 192 blood samples were collected from ewes of both farmers’ and institutional flocks comprising sheep populations of Jamuna River Basin (JRB), Barendra (BAT), Coastal (COR), Garole (GAR) and Muzaffarnagari (MUZ). Genotyping of the individuals was performed using PCR-RFLP method and single marker association analysis was carried out to evaluate the relationships between resultant genotypes and litter size trait using agricolae and pastecs packages of R software. The prolificacy attributed homozygous FecBBB genotype frequencies were 66, 50 and 55%, respectively in JRB, BAT and GAR populations whereas it was only 0-2% in MUZ and COR populations. Association analysis revealed highly significant (P&lt;0.001) association of litter size trait with genotypes and populations. The mean litter sizes of JRB, BAT, GAR, COR and MUZ were 2.17±0.15, 1.88±0.07 1.90±0.10, 1.12±0.03 and 1.02±0.02, respectively. The prolific JRB, BAT, GAR ewes produced 0.67 to 0.83 more lambs per lambing than their wild type FecB++ counterparts. Thus, this study validated the potential contribution of the investigated c.746A&gt;G SNP that could be applied in marker assisted selection (MAS) program for identifying high prolific ewes in order to improve litter size trait at the population level

Parameters of breeding traits of sheep of the new breed Artlukhsky merino

The planned breed for breeding in the Republic of Dagestan is Dagestan mountain breed. However, from sheep of this breed fine merino wool is not obtained, and the breeding of special merino breed for mountain and transhumant breeding system is an urgent problem. The purpose of the research was to characterize the main breeding traits in different sex and age groups of sheep of the new breed Artlukhsky merino, such as live weight, wool shearing and its qualitative parameters. Artlukhsky merino breed was bred by using Dagestan mountain breed on the ewes at the beginning stage of the rams of Stavropol breed, and at the final stage – Manych merino breed. The research of the parameters of the breeding traits has been made on elite and class I animals in the breeding farm of the APC “Krasny Oktyabr” in the Kazbekovsky area in the Republic of Dagestan. The live weight of sheep of different sex and age groups of the tested breed was 45–97 kg. The average fineness of wool fibers in adult rams was 23,3 microns (60 quality), in ewes – 22,9 microns (64 quality), in rams aged 12 months – 22,1 microns and young ewes – 20,9 microns (64 quality). The difference in the fineness of the wool on the side and thigh did not exceed one quality. The length of the wool fibers on the side on average in adult rams was at least 9,9 cm, in ewes – 9,4 cm, in young ewes – 10,2 cm and young rams – 10,4 cm. The yield of washed wool in the herd was at the level of 64 %, the fertility of ewes was 125 to 135 %. Thus, the indicators of the main selected traits in sheep of the new breed Artlukhsky merino are at the level of the best domestic breeds, such as Volgograd and Vyatka.

PSXI-24 Evaluation of Barbados Blackbelly and St. Croix hair sheep under accelerated lambing using purebred and terminal sire mating: Ewe fertility, prolificacy, and productivity

Abstract Objectives were to evaluate ewe performance under an accelerated, pasture-lambing system. Barbados Blackbelly (n = 85) and St. Croix ewes (n = 91) were exposed to rams of their own breed (pure) or Dorset (terminal) in November (2012 and 2014), July (2013 and 2015), and March (2014 and 2016). Traits considered were fertility (i.e., ewes lambing/ewes exposed; n = 670) and number of lambs born (NLB), number of lambs weaned (NLW), and total 65 d adjusted litter weaning weight (LWW; n = 548 each). Data were analyzed with fixed effects of ewe age (1, 1.5, 2 yr, or ≥ 2.5 yr), breed, mating system (pure vs terminal), mating month-year, and the mating system x mating month-year interaction and a random ewe effect. Fertility was greater for Barbados Blackbelly than St. Croix ewes (0.88 vs 0.73; P &amp;lt; 0.01) but ewe breed did not affect any other trait (P ≥ 0.06). The mating system x mating month-year interaction effect impacted all traits (P ≤ 0.03) except NLB (P = 0.09) and performance between mating systems was compared within mating month. Fertility was greater for pure than terminal mated ewes in November (0.96 vs 0.85) and July (0.94 vs 0.53; P ≤ 0.01). Following July mating, both NLB and NLW were greater for pure than terminal mated ewes (1.69 vs 1.37 lambs and 1.43 vs 1.11 lambs, respectively; P &amp;lt; 0.01). However, LWW was greater for terminal than pure mated ewes after November (18.0 vs 15.7 kg) and March mating (18.1 vs 14.2 kg; P ≤ 0.02). Using a terminal sire in landrace hair sheep under accelerated mating generally reduced fertility, NLB, and NLW but improved LWW. The strategic use of terminal sire mating should be considered just during breeding season, or the use of alternative sire breeds should be evaluated.

Appearances of Local Prolific Ewes in Semarang Regency Central Java Indonesia

The present study examined the quantitative and qualitative physical parameters of prolific local ewes in Bawen and Jambu districts, Central Java. We used purposive sampling to select and categorized 132 local, three-lambing ewes into three groups based on their prolific capacity: 66 single, 49 twins and 17 triplets. The data were subjected to analysis of variance using Chi-Square. The result showed that many quantitative properties of prolific ewes resembled those of fat-tailed sheep: thin tail, highly significant (P&lt;0.01) compared to fat tails; straight face, highly significant (P&lt;0.01); and fewer convex face and short body, significant (P&lt;0.05) with a tall body in the non-prolific ewes. Few prolific ewes had big ears and black-white wool and significantly different (P&lt;0.05) from the non-prolific ewes. Conclusively, local prolific ewes had a qualitative appearance more closely related to that of thin-tailed ewes, but greater quantitative performances than the non-prolific ewes.