Young Ewes Research Articles

COMPARISON OF NEUTROPHILAND LYMPHOCYTE (N/L) RATIO IN SAPERAAND CROSSBRED ETAWAH GOATS IN SAYEGAN, SLEMAN, YOGYAKARTA AND ITSSOROUNDING AREA

Neutrophil and lymphocyte ratio (N/L) can be used as a chronic stress indicator inanimal. Increase of N/L ratio indicates stress in animal that marked by neutrophilia and lymphopenia. The study was aimed to determine the comparison of N/L ratio in Sapera an Ettawah crossbreed goats.The samples of this study were obtained from 126 Sapera goats and 99 Ettawah cross breed goats with various physiological condition status (rams, pregnant ewes, nanny goats, ewes, young rams, young ewes, and lactating goats)that are clinically healthy from farm in Seyegan, Sleman, and its surrounding. Blood samples were taken through jugular vein in the morning, the blood smear were made to calculate leukogram. The average calculation results of N/L ratio in Sapera goat group is 0.55±0.,57and Ettawah crossbreed goat group is 0.47±0.44.The results of the statistical analysis using the One-Way Analysis of Variance test showed an insignifi cant difference in the N/L ratio (p > 0.05) between groups of Sapera and Ettawah crossbreed goats. It can be concluded there was no significant influence of the breed and physiological status difference in Sapera and Ettawah crossbreed goat's blood N/L ratio.

Productivity and resistance of sheep depending on the grazing period duration

Abstract The purpose of the research is to establish the productive qualities and resistance of the sheep organism at different periods of keeping sheep on pastures. Studies on improving the pasture use system were carried out on three groups of sheep with the beginning of the pasture season on April 25: Group I – with the end of the pasture season on October 15, II – on November 15, and III – on December 15. The data obtained indicate that the females kept on pastures for a longer time exceeded their peers of other groups by 1.6-2.0 kg in live weight. Before being driven to pastures on April 20, their live weight also turned out to be higher by 0.8-1.2 kg, and during their stay on pastures – by 0.7-1.6 kg, which indicates the expediency of longer grazing of sheep. In terms of live weight, the superiority of late weaning compared to the average was 1.25%, over group I (early term) – 5.23% (P>0.95). The blood of young ewes with a long grazing period contained more leukocytes, gamma globulins, erythrocytes and, most importantly, hemoglobin.

PSIX-24 Greater glucose transporter SLC2A1 expression in milk somatic cells as a compensatory milk production strategy in young prolific Pelibuey ewes

Abstract The number of lambs per birth expressed as prolificacy is a key trait that determines productive efficiency in sheep. However, the optimal litter size depends on the production system, since the milk production of the ewe impacts the postnatal development of lambs. Milk yield, in turn, is related to the expression of the SLC2A1 gene in mammary epithelial cells. This gene encodes the solute carrier/glucose transporter 1 and is upregulated in peak/mid lactation. To assess the productive efficiency of twinning ewes in regard to SLC2A1 expression, the objective of this study was to measure the mRNA levels of SLC2A1 in milk somatic cells (MSC) of Pelibuey ewes lambing twins. Healthy ewes (n = 8), three primiparous and five multiparous, were selected to quantify and compare abundance of SLC2A1 mRNA. Management was under feedlot conditions, and the milk samples were taken between 16 and 20 d post-lambing. Total RNA was purified from MSC and SLC2A1 mRNA abundance were measured by RT-qPCR, relative to β-actin as reference gene. The total birth weight (TBW) and weaning weight of their lambs were recorded, calculating the total weight of lamb weaned (TWLW). TBW, TWLW and relative expression of SLC2A1 were analyzed with PROC GLM of SAS, whereas the Pearson correlation coefficient between TWLW and relative expression of SLC2A1 was calculated using PROC CORR of SAS. Although there was no statistical difference in TBW (P = 0.13) and TWLW (P = 0.38) between lambing groups, a numerical difference was observed both in TBW (5.7 ± 0.54 and 6.9 ± 0.42) and in TWLW (21.5 ± 3.94 and 26.2 ± 3.05) for primiparous and multiparous, respectively. The abundance of SLC2A1 mRNA were 3.1-fold change (P = 0.0005) greater in MSC of primiparous ewes than in the multiparous ones (Figure 1). In multiparous ewes a positive correlation, r = 0.96 (P = 0.01) was found between TWLW and relative expression of SLC2A1. It is concluded that greater relative expression of SLC2A1 in young prolific ewes could be a compensatory mechanism to produce more milk to feed their lambs, even with a smaller udder volume. Such findings give way for further research on the subject.

Effects of β-carotene supplementation and age on the oxidative status, production and reproductive performance of grazing ewes

Context There is some evidence that physiological stages such as breeding, pregnancy, parturition and lactation may trigger oxidative stress. It has also been observed in several species, including sheep, that age affects their vulnerability to oxidative stress. Aims This study investigated the effects of supplemental β-carotene and age on the oxidative status of grazing ewes around breeding, pregnancy, parturition and early lactation as well as on their production and reproduction performance. Methods Hundred and four ewes were divided into two broad age groups (young = 1–3 years, and old = 4–6 years). Within age groups, ewes of similar age were randomly assigned to four treatment groups (A1, A2, A3, C) by using a completely randomised block design. The young (n = 13) and old (n = 13) sheep in Groups A1, A2 and A3 were daily drenched with 100 mg, 75 mg and 50 mg β-carotene respectively. Group C was unsupplemented (Control). Supplementation lasted 28 days before oestrus synchronisation; 14 days during oestrus synchronisation (CIDR) and hand-mating; 18 days post-hand-mating; 30 days before lambing; and 15 days after lambing. All animals were grazed on Kikuyu grass (Pennisetum clandestinum). Six ewes from each group (total = 24) were sampled for blood to measure oxidative and hormonal status during the experiment. Key results Supplemental β-carotene at ≥75 mg/day may act as a pro-oxidant in ruminants under oxidatively stressed conditions such as parturition. Age did not affect the ewes’ oxidative status. The supplemental β-carotene did not affect bodyweight, oestrus parameters, corpus luteum size, conception rate and litter size. Except for a tendency of lambs from supplemented ewes to have heavier weight at 15 days old (P = 0.080), age group and supplemental β-carotene did not affect the lamb mortality rate or weight at birth or 15 days old. Older ewes showed earlier and longer duration of oestrus than did younger ewes. Conclusions Supplementation of grazing ewes with β-carotene should not be ≥75 mg/day, especially at parturition period, because it may work as a pro-oxidant. The older ewes seem to have earlier oestrus with a longer duration than do the younger ones. Implications Caution is urged when administering high doses of β-carotene to ewes during the peri-parturient period.

Mетаболічна та продуктивна дія удосконалених за складом БВМД у раціонах годівлі молодняка овець

The article presents the results of the study of productive and metabolic effect of the use of a protein-vitamin-mineral supplement (PVMS), an improved formulation, as part of the feeding rations of young repair ewes of the Ukrainian mountain-Carpathian breed in the conditions of the natural-climatic zone of the Carpathian foothills, by introducing into their composition local highly nutritious feed components. The research was carried out during a two month period (February – March) in the conditions of the Radvan-Nova farm (Myloshevychi village, Pustomytivskyi district, Lviv region) on young ewes of the above breed in the winter-spring stall period. For this purpose, three groups of 12-month-old young ewes of 10 heads in each group (control and two experimental) were formed by the method of analogues, which were kept separately with the provision of proper care and level of feeding. The feeding ration consisted of meadow grass-herbaceous hay (unlimited), oat-pea straw (unlimited) and compound feed. The calves of the control group received 0.4 kg of standard compound feed according to the recipe of the ITSR named after M. F. Ivanov "Askania-Nova", the young ewes of the first experimental group – the same amount of experimental compound feed, the young ewes of the second experimental group – 0.3 kg of a mixture of whole grains of oats, barley, corn and 0.1 kg of experimental PVMS. The conducted studies established that, in the conditions of the indicated climatic zone, feeding of 12-14-month-old young ewes with the rations of compound feed and PVMS including local feed ingredients in their composition, compared to standard analogues, provides an increase in indicators of weight and linear growth of animals, a decrease in monetary expenditure on increases in live weight, improves biochemical indicators of metabolism in the blood. It is also shown that the use of compound feed and PVMS of an improved recipe compared to standard feed, when growing repair young ewes of the Ukrainian mountain-Carpathian breed aged 12–14 months in the winter-stall period makes it possible to reduce monetary costs for obtaining 1 t of growth gain by 10–13%

Utilising male stimulus to improve the reproductive efficiency of 8-month-old nulliparous ewes and adult parous ewes

We tested whether utilising the male effect to stimulate ewes before the mating period can reduce the time to conception following the introduction of entire rams, and increase fertility, prolificacy, and reproductive rate (number of fetuses per 100 ewes exposed to fertile rams). A retrospective analysis was used to analyse records from 59,716 ewes collected over 34 years (1986–2020) from seven genotypes: Border Leicester, Composite (crossbred), Dorset, Merino, Dorset x Polypay, Rambouillet, White Suffolk. The dataset also included nulliparous young ewes (mated at age 8 months) and adult parous ewes. Vasectomized rams were used to stimulate 20,632 ewes before a mating period that lasted 2 or 3 estrous cycles, and the outcomes were compared with those from 39,084 ewes that had not been stimulated. Independently of genotype, utilising the male stimulus advanced the average conception date by 8 days for young ewes (P < 0.0001) and by 1 day for adult ewes (P < 0.0001). The male stimulus also increased the proportion of ewes that conceived in their first cycle by 33 % for young ewes and by 6 % for adult ewes (P < 0.0001). For the cycle of conception, there were significant (P < 0.0001) effects of two interactions: male stimulus x age at mating and male stimulus x live weight at mating. The male stimulus improved fertility in both adult ewes (99.8 % vs 89 %; P < 0.001) and young ewes (77.7 % vs 81.3 %; P < 0.001). The male stimulus increased the number of young ewes (41.9 % vs 11.1 %; P < 0.001) and adult ewes (16.6 % vs 2.7 %; P < 0.001) that conceived multiple fetuses in the first 17 days of the mating period. The reproductive rate was improved by the male stimulus in young ewes (129 % vs 135 %; P < 0.001) but not in adult ewes (120 % vs 122 %; P = 0.12). When all animals for all breeds were included in the analyses, there were improvements in fertility, prolificacy, and reproductive rate as age and live weight increased at mating (P < 0.0001). We conclude that, independently of genotype, utilising the male stimulus before the mating period reduces the time to conception and improves reproductive performance in both young and adult ewes.

Secretory IgA as Biomarker for Gastrointestinal Nematodes Natural Infection in Different Breed Sheep.

Specific IgA antibody has been shown to play an important role in resistance to gastrointestinal nematode (GIN) infections in sheep, particularly in Teladorsagia circumcincta parasitosis. In some breeds, negative associations have been shown between IgA levels and worm burden in experimentally infected sheep. In the present study, we have studied the relationship between IgA levels in naturally infected sheep (582 ewes in total; 193 younger than one year old and 389 older than one year old) and fecal egg count (FEC) in the Assaf, Castellana, and Churra breeds. ELISA assays were performed to measure IgA levels against the somatic antigen of T. circumcincta third larval stage (L3) and a 203-amino-acid fragment of the protein disulfide isomerase from the same GIN species. A multilevel random intercept model was developed to predict the infection risk according to age or breed. Spearman's correlation rank was used for statistical analysis. The prediction model showed that breed was not an influential factor in this study, although the Assaf breed could be considered slightly more susceptible than the others. In addition, age affected the infection risk, with the young ewes more susceptible to infection than the adult groups, except for the Castellana breed, whose risk of infection was similar at all ages. The most significant positive association was found between FEC and IgA measured in the nasal secretions of young ewes using both antigens (Rho = 0.5; p = 0.00); the correlation of FEC with IgA in serum was moderately significant (Rho = 0.306; p = 0.00). Comparing both antigens, the protein disulfide isomerase antigen was less reactive than the somatic antigen from L3. In conclusion, under natural conditions, specific IgA against GIN was positively associated with FEC in sheep, with nasal secretions from young animals being the sample where this association is stronger, which, therefore, could be used as a marker of infection in further studies.

Timing and duration of nutrient restriction and its impacts on placental development and umbilical blood flow in adolescent sheep

We hypothesized that nutrient restriction from day 50–90 of gestation decreases umbilical blood flow and that umbilical blood flow would recover to control values upon realimentation during late gestation (d 90 to 130) or remain reduced in ewes that continued to be nutrient restricted. On d 50 of gestation, young nulliparous whiteface ewes (6–8 mo; n = 41) carrying singletons were randomly assigned to two dietary treatments: 100% of NRC recommendations (CON) or 60% of CON (RES). On d 90 of gestation, ewes either remained on CON or RES until d 130, or CON ewes were RES from d 90 to 130, or RES ewes were realimented to CON from d 90 to 130. This resulted in 4 treatment groups on day 130: CON–CON, CON-RES, RES-RES, RES-CON. Umbilical blood flow and fetal and placental measurements were obtained via ultrasonography every 10 days from day 50–110. Non-survival surgeries were performed on days 50, 90, and 130 (n = 6–7 ewes/group) where uterine artery and umbilical blood flows were measured during surgery via ultrasonography. Conceptus weights were recorded and placentomes collected to determine binucleate cell numbers. The study was conducted as a completely randomized design arrangement with repeated measures. Data were analyzed using the MIXED procedure of SAS. There was a nutritional treatment by day interaction (P < 0.01) with CON ewes having greater umbilical blood flow compared with RES by d 90. Fetal biparietal distance, abdominal width, and kidney area increased (P < 0.05) in CON-RES with all these measurements increasing during late gestation. We partially accept our hypothesis as nutrient restriction during mid gestation decreased umbilical blood flow. However, blood flow did not return to control levels upon realimentation. By d 130, fetal and placental weights were similar between RES-RES and CON–CON. Binucleate cell numbers in the fetal trophoblast were not influenced by nutritional treatments. Our findings suggest that refeeding previously nutrient restricted pregnant adolescent ewes to control levels does not reestablish umbilical blood flow. Adequate placental development during mid gestation could protect the fetus from a decreased umbilical blood flow later in gestation when nutrients were limited by 40%.

Small Ruminant Lentivirus Infection in Sheep and Goats in North Portugal: Seroprevalence and Risk Factors.

Small ruminant lentiviruses (SRLVs) are transmitted among ovine and caprine species. This disease is a severe problem for small ruminant production, not only for animals' well-being but also for flocks' efficiency. The main aim of this research was to quantify the seroprevalence and associated risk factors for SRLV infection in the northern region of Portugal. Samples were collected from a total of 150 flocks, of which 129 (86.0%; 95% CI: 80.67%-91.33%) had at least one seropositive animal. Out of 2607 individual blood samples, 1074 (41.2%) were positive for SRLVs. Risk factors associated with SRLV infection were species (caprine), age (>2 years old), flock size (>100 animals), production system (intensive), food production system (milk), type of activity (professional), participation in livestock competitions (yes), replacement young ewe bought (yes), and natural feeding management (yes). This knowledge empowers the implementation of effective preventive measures. Overall, biosecurity measures should be promoted and implemented with the main aim of reducing viral transmission and reducing the prevalence of this disease. We recognise that government authorities should promote and audit voluntary control and eradication programs in small ruminant flocks in the region studied.

Effect of yeast probiotic supplements in the diet of young ewes on the metabolic activity of rumen microbiota

1. Ahlam R.A., 2011. Utilization of Saccharomyces cerevisiae supplementation for feeding goats in South Sinai. Egypt. J. Nutr. Feeds 14, 169–181 Google Scholar

WOOL PRODUCTIVITY AND QUALITY OF RUSSIAN MEAT MERINO SHEEP FROM INTRA- AND INTERLINE SELECTION

Line breeding is often used in purebred animal husbandry, although the combination of lines may affect undesirable result. Therefore, it is very important for animal breeders to know which lines of animals can be combined to produce highly productive offspring with high meat and wool properties. This article studies the influence of interline selection of Russian meat merino breed on wool productivity, quality and skin histostructure. We found that the highest clipping was in the animals of group III obtained from ME-50 line rams and AS-30 line ewes. Ewes exceeded their peers of group II from the intraline AC-30 selection and peers of group IV from AS-30 line rams and ME-50 line queens. At the same time, ewes of group III insignificantly exceeded peers of group I from intraline selection of ME-50 line animals by 2.0% (P&gt;0.05). Animals of group III had rather high fleece indices in terms of the wool condition due to the influence of ME-50 rams. Moreover, they had the highest ratio of “fat:sweat” (0.84), which confirms the high technological wool properties of this genotype. The quality of sheepskins depends on the nature of the connection of collagen fibers in the reticular layer. In terms of the thickness of the skin reticular layer young ewes of the group III exceeded their peers in groups I, II and IV by 5.3% (P&gt; 0.05), 21.9% ( P&lt;0.01) and 12.0% (P&lt;0.05) respectively.

An investigation of pathways for rebuilding Australia’s sheep flock

Context A significant opportunity remains to further increase the supply of premium sheepmeat products to Australia’s customers, which requires a more rapid rebuilding of the national sheep flock. To help meet this challenge, developing relevant information for sheep producers to assist them to achieve a profitable flock-rebuilding outcome is viewed as highly desirable. Aims (1) Develop flock-rebuild scenarios that track inventory, cashflow, profit and loss, and the overall balance sheet over a 5-year projection. (2) Model the impact on flock-rebuilding pathways of exposure to variation in supplementary-feed costs, purchase of stock and price received for sale animals and flock structure. (3) Model variation in benefits and costs for a range of production zones, enterprise types and flock-age profiles. Methods Fourteen flock-rebuilding pathways were assessed for up to nine flock types, using a spreadsheet model that tracked inventory, cashflow, profit and loss, and the overall balance sheet over 5 years. Key results The top four pathways for profitability and capacity to rapidly rebuild flock numbers include retention of more older ewes, purchasing young ewes, purchasing older ewes (mostly 5–6-year olds) in Merino and Merino-cross flock types only and joining ewe lambs in Maternal and Cleanskin flock types only. These pathways were not sensitive to variation in the cost of supplementary feed, stock prices or flock structure, although joining Merino ewe lambs became one of the top four pathways when feed costs were lower. Conclusions and implications The well established practices of retaining ewes for longer and purchasing ewes, especially young ewes, have the most potential to both rapidly and profitably rebuild flock numbers. However, joining ewe lambs, particularly in Maternal and Cleanskin flocks, can also profitably contribute to rapid flock rebuilding. While reducing reproductive wastage or increasing reproductive potential were mostly profitable, they could not rapidly rebuild flock numbers. In contrast, accelerated lambing systems can rapidly rebuild flock numbers, but are only marginally profitable.

In vitro embryo production from ewes at different physiological stages.

The collection of ovaries from slaughterhouses is an important source of oocytes for in vitro embryo production. On the other hand, the physiological stage of slaughtered females varies and influences embryo production. The study examined the in vitro efficiency of embryos and demi-embryos from young, non-pregnant adult, and pregnant adult ewes from a local slaughterhouse. One thousand three hundred ovaries were collected from August to October 2020. The recovered oocytes were matured, fertilized, and cultured at 5% CO2, 38.5°C, and 100% humidity. Embryo bisection was performed in 96 blastocysts (n = 32 per treatment). The demi-embryo pairs were incubated for their reconstitution for 12 h. SAS was used for data analysis. The number of oocytes collected from the experimental group of non-pregnant adult ewes was higher (p ≤ 0.007) than those collected from the group of pregnant adult ewes (2.67 ± 0.19 vs. 2.18 ± 0.15 oocytes/group, respectively). The blastocyst rate was higher (p ≤ 0.0001) in the non-pregnant adult group (36.39%) than in the young (17.96%). The ratio of demi-embryos that recovered the blastocoelic cavity was higher (p < 0.05) in the young group (81.25%) than in the pregnant adult group (59.38%). The diameter of the demi-embryos was higher (p < 0.05) in the non-pregnant adult group (186.54 ± 8.70 μm) than those in the young and pregnant adult groups. In conclusion, the in vitro embryo production efficiency was highest when using oocytes from non-pregnant adult ewes under the conditions of this study.

Questions of admixture crossing in semi-fine-wool sheep breeding in Kyrgyzstan

The paper deals with the use of admixture crossing in semi-fine-wool sheep breeding in Kyrgyzstan and its results. The purpose of the research was to develop and scientifically substantiate the methods of using the North Caucasian meat and wool breed during admixture crossing for further improvement of the Tian Shan sheep breed. Generally accepted zootechnical methods were used (the classical scheme of introductory crossing), wool qualities were determined on the OFDA device – 2000. The half-blooded (1/2SKTSH) and quarter-blooded (1/4SKTSH) North Caucasian Tian Shan young animals have better wool qualities without reducing the live weight of the crossbreeds. At the same time, the crossbreeds obtained from the back crossing with wool of 58-56 quality in the specific weight of the herd reached 85.5%, and with the most desirable degree of fineness of 56 quality – 63.3%. According to wool density (M+), the proportion of mixed bred young ewes reached 33.3%, which was 25.2% more than that of half-bloods. It was revealed that the inheritance of wool density trait as a result of crossing these breeds had a positive effect on wool productivity. The crossbred wool cut from them had the best marketable appearance. All this makes it possible to switch to the breeding of quarter-blooded North Caucasian Tian Shan animals “in itself” in the future.

Reproductive performance in two organic sheep farming systems differing by the number of mating sessions in and out of the breeding season

Hormonal treatments to control ovulation and the intensification of reproduction rhythm are usual strategies to increase ewe productivity. However, in organic farming the use of hormones is banned, making any increase of reproduction rhythm an inappropriate practice. This work tested if increasing the number of mating sessions per year could improve ewe annual productivity, while maintaining a non-intensive reproduction rhythm of one lambing per ewe per year. Reproductive performance was studied over five years in two organic sheep farming systems differing by the number of mating sessions (MS) per year, two (2MS) or four (4MS). The 4MS system included two mating sessions in the breeding season (September and November) and non-breeding season (April and June). The 2MS system included mating in November and April. Non-pregnant ewes were recycled one (2MS) or two times (4MS system) on consecutive mating sessions. Considering all mating attempts per ewe individually (n = 1366), the time elapsed from mating to lambing (159 ± 0.2 days), fertility (86%), prolificacy (166%) and productivity (143%) did not differ between the systems (P > 0.05). Fertility, prolificacy and productivity were higher in the breeding than the non-breeding season (P ≤ 0.05), and in adults than young ewes (P ≤ 0.05), without interaction with the systems (P > 0.05). In the non-breeding season, fertility, prolificacy and productivity did not relate to ewe cyclic status (P > 0.05), whereas the time elapsed from mating to lambing was shortened in cyclic ewes (P ≤ 0.05). Good ewe body condition at lambing and mating and dynamic gain in body condition from drying to mating improved productivity (P ≤ 0.05) by increasing fertility or prolificacy regardless of the system (P > 0.05). On a yearly scale, the number of lambed ewes was higher in the 4MS than the 2MS system (91% vs 85%; P ≤ 0.05) leading to higher ewe annual productivity (154% vs 141%; P ≤ 0.05). The percentage of ewes that were recycled on consecutive mating sessions was higher in the 4MS than the 2MS system (24% vs 18%; P ≤ 0.05), possibly explaining the 4MS increase of ewe annual productivity by extending mating opportunities for the ewes. The increase in the number of mating sessions per year is a hormone-free strategy suitable for organic sheep farming systems to improve annual ewe productivity on a basis of one lambing per ewe per year. This approach proved beneficial to compensate for lower fertility in the non-breeding season, especially for young ewes.

Growth and development of young sheep of Edilbaev breed under the conditions of farm in the Republic of Kazakhstan

The features of growth and development of young animals of Edilbaev breed obtained from sheep bred under the production conditions of the farm “Birzhanov” in the Auliekolsky area in the Kostanay region of the Republic of Kazakhstan have been studied in the paper. In a comparative aspect the live weight was studied, the conformation features of the young sheep of Kazakh fat-tailed rough-haired and Edilbaev breeds were determined. Two groups of sheep were formed for the research: a control group (Kazakh fat-tailed rough-haired breed) and an experimental (Edilbaev breed) with 15 heads in each group. Studies have shown that with the same housing and feeding of animals of diff erent breeds, the gain in live weight was diff erent. The largest absolute gain in live weight was shown by young rams and young ewes of Edilbaev breed 11,3 and 10,0 kg, while young rams and young ewes of Kazakh fat-tailed rough-haired breed only 10,3 and 8,8 kg. The highest growth rate in sheep of the experimental groups was observed until the age of one month. In other age periods the growth rate was signifi cantly infl uenced by feeding conditions, however, in general, the growth rate of young animals was high. When studying the conformation features of the experimental young sheep, it was found that with age the conformation of the lambs of the experimental group changed in the same way as in the control group, however, high indices of blockness and massiveness allow us to state that the lambs of the experimental group have well-developed meat forms. Studies have shown that there is a significant difference in the experimental young animals of the compared groups in terms of live weight, body measurements and conformation indices in favor of sheep of Edilbaev breed.

Effects of Mid-Gestation Nutrient Restriction, Realimentation, and Parity on the Umbilical Hemodynamics of the Pregnant Ewe

Previous studies have reported that nutritional restriction from days 50 to 130 applied in young nulliparous ewes reduces umbilical blood flow (UBF). We hypothesized that during restriction, UBF and fetal and placentome dimensional measurements would decrease compared to adequately fed ewes, but upon realimentation, ewes would have similar UBF as ewes that were not restricted. We also hypothesized that multiparous ewes would be more resilient to nutrient restriction compared to nulliparous ewes. In experiment 1, second-parity Dorset ewes carrying singletons were assigned to an adequate nutrition group (CON, n = 7) or a restricted (60% of CON) group (RES, n = 8), from days 50 to 90 of gestation. In experiment 2, on day 50 of gestation, adult (15-month) nulliparous (NUL; n = 12) and multiparous (MUL; n = 16) Dorset ewes carrying singletons were randomly assigned to receive 100% of NRC recommendations (CON) or 60% of CON (RES). On day 90, all ewes were fed 100% of nutritional recommendations according to body weight. Ewe body weight and conceptus measurements via ultrasonography were recorded every 10 days from days 50 to 130 of gestation. We measured 10 random placentomes, fetal biparietal and abdominal length, and kidney length and width. Doppler mode was used to obtain UBF, pulsatility index (PI), and resistance index (RI). Lamb weight and parturition problems were recorded. In experiment 1, on day 80, UBF decreased (P ≤ 0.05 means separation of unprotected F test), placentome size tended to decrease (P ≤ 0.10), and PI and RI tended to increase in RES vs. CON ewes (P ≤ 0.10). In experiment 2, there were no three-way interactions or main effects of treatments on UBF, PI, RI, and placentome size (P ≥ 0.57). There was a parity-by-day interaction (P &amp;lt; 0.05) for RI, but UBF was not affected by parity or diet. After realimentation, there was no effect of treatment on ultrasound measurements in both experiments. At birth, lambs and placental measurements were not different (P ≥ 0.43). Restriction from days 50 to 90 does not seem to influence umbilical hemodynamics or conceptus growth in adult white face sheep, regardless of parity.

Toxoplasma gondii is not an important contributor to poor reproductive performance of primiparous ewes from southern Australia: a prospective cohort study

BackgroundToxoplasma gondii causes reproductive losses in sheep worldwide, including Australia. The reproductive performance of primiparous ewes is typically lower than for mature, multiparous ewes, and younger ewes are more likely to be immunologically naïve and therefore more susceptible to reproductive disease if T. gondii infection occurs during pregnancy. The aim of this study was to assess the impact of infection with T. gondii on the reproductive performance of primiparous ewes in southern Australia using a prospective cohort study. This will inform the need for targeted control strategies for T. gondii in Australian sheep.ResultsToxoplasma gondii seropositivity using indirect ELISA was detected at 16/28 farms located across southern Australia. Apparent seropositivity to T. gondii was lower in primiparous ewes (1.1, 95% confidence interval (CI) 0.6, 1.8) compared to mature, multiparous ewes (8.1, 95% CI 6.0, 10.5; P < 0.001). Toxoplasma gondii seroconversion during the gestation and lambing period was confirmed for 11/1097 (1.0, 95% CI 0.5, 1.7) of pregnant primiparous ewes that failed to raise a lamb, and 1/161 (0.6, 95% CI 0.1, 2.9) primiparous ewes with confirmed mid-pregnancy abortion.ConclusionsLow frequency of detection of T. gondii seroconversion during gestation and low frequency of seropositivity to T. gondii suggests that toxoplasmosis was not an important contributor to reproductive losses in primiparous ewes on farms located over a wide geographical area in southern Australia.

Effect of adaptogen lithium ascorbate on the microbiota of rumen in young ewes

Health and productivity of ruminants directly depend on the state of rumen and digestion in intestinal tract. Normal microflora protects the body from pathogenic microbes, stimulates the immune system, participates in metabolic reactions and plays an important role in energy metabolism. Disturbance of species composition of microflora in rumen under effect of various factors leads to a state of dysbiosis, disorders of products digestibility, changes in enzymatic processes and other disorders. Biologically active substances of an adaptogenic nature can show immunomodulatory and antimicrobial activity. Adaptogen lithium ascorbate has stress-protective, neurotrophic, neuroprotective, antioxidant, immunomodulatory properties. In this paper, using molecular genetic methods, the effect of lithium ascorbate on composition of rumen microbiota of sheep was studied for the first time. Composition of microbiota was determined by NGS sequencing method. In total, 37 phylums, 76 classes, 98 orders, 225 families and 894 species of microorganisms were identified. It has been determined that introduction of lithium ascorbate at a dose of 10 mg/kg of body weight into the main diet of sheep contributed to increase in proportion of cellulolytic bacteria from 73.6±1.6% to 75.4±0.9% and over 40% decrease in total number of infusoria in rumen content. Cellulolytic activity of rumen fluid in sheep of the experimental group increased by 38% compared to the animals of the control group. The number of pathogenic bacteria decreased from 2.7% in sheep of the control group to 1.6% in animals of the experimental group, while the content of beneficial bacilli increased from 0.3% to 0.5%, respectively. Content of undesirable and conditionally pathogenic microflora decreased in the sheep of experimental group. The obtained data confirm positive effect of adaptogen lithium ascorbate, introduced into diet at a dosage of 10 mg/kg of body weight, on qualitative and quantitative composition of microbiota in sheep rumen. Therefore, lithium ascorbate, a broad-spectrum adaptogen, can be recommended as a feed additive to the main diet of sheep to improve rumen digestion and increase productivity.

MAIN INDICATORS OF THE WOOL QUALITY OF DNIPROVIAN MEAT BREED SHEEP OF DIFFERENT SEXES AND GENOTYPES

The formation of comprehensive knowledge of the assessment of physical and technical parameters of sheep wool depending on sex and genotype is one of the problems of animal biology, which is due to the requirements of the theory and practice of sheep breeding, as well as the wool processing industry, although the production of an increasing number of synthetic and artificial fibers. Actually obligatory evaluation of physical and technical parameters of wool is regulated by the current state standards and instructions on conducting breeding work, which determines productivity of selection in relation to further improvement of sheep breeds. However, the available information in the prevailing majority of literature sources on the quality of wool concerns sheep of meat-wool and wool-meat direction of productivity. As for sheep of meat production, in particular the newly created domestic breeds such materials are almost absent which determines the relevance of the work done. The foregoing article presents the results of the laboratory evaluation of differences in quality indicators of wool of the Dnieper beef sheep breed in relation to their sex and genotype. The research objects are young ewes, heeders, ewes and tupping rams. The experiments have been conducted in the conditions of the analytical laboratory for evaluation of wool quality and the breeding center for sheep breeding of the Institute of animal sciences NAAS. The obtained data indicate that young ewes of the line 024/063 (Ml) have a larger length of wool on the compared topographic areas of the fleece, such as on the back (by 23-69%), maw (by 25-30%), thigh (by 2,5-4,6%). The larger length of wool on maw is characteristic of ewes and tupping rams of this line. The sheep of all sex and age groups, which belonged to the line 024/063 (Ml) are reported to be characterized with the highest wool alignment by length within the evaluated topographic areas of the fleece. In spite of the mentioned differences in the indicator of wool fineness, the examinee sheep of these groups are quite homogeneous. The wool fineness in the groups of ewes and young ewes is within the range of 58-60 quality assortments, while the wool fineness of the replacement heeders and the tupping rams is within the range of 56-60 quality assortments.