Associations among Mammary Ultrasound Measurements, Milk Yield of Non-Dairy Ewe Lambs and the Growth of Their Single Lambs

Mammary cistern size was positively correlated with milk yield of mature dairy ewes, but the association in ewe lambs is unknown. This experiment aimed to examine the associations between mammary ultrasound measurements and the milk yield of ewe lambs at one year of age and to determine the accuracy of using maternal mammary ultrasound to predict single lamb growth rates. Single-bearing ewe lambs (n = 45) were randomly selected and 30 were milked once at weeks three (W3), five (W5), and seven (W7) of lactation. Mammary ultrasound scans were performed at day 110 of pregnancy, W3, W5, W7, and weaning (L69). Single lambs (n = 30) were weighed at birth and at each mammary scanning event. Udder measurements explained 26.8%, 21.4%, and 38.4% of the variation in milk yield at W3, W5 and W7, respectively, and 63.5% and 36.4% of the variation in single lamb growth to W3 and to L69. This ultrasound technique was more accurate in predicting single lamb growth to W3 than milk yield and may enable the identification of pregnant ewe lambs whose progeny would have greater growth rates. More research is needed to identify accurate indicators of superior milk yield and determine whether ultrasound could be used to select ewe lambs.

Determination of pregnancy protein levels to distinguish between singleton and twin pregnancies in Awassi sheep

Determining the fetal number to avoid pregnant sheep management, feeding, and delivery issues is of vital importance. This study aimed to determine the levels of pregnancy-associated glycoprotein (PAG) and pregnancy-specific protein B (PSPB), which are pregnancy proteins, to accurately predict singleton and twin pregnancies in Awassi sheep. A total of 40 Awassi sheep were used for the study. According to the number of offspring, pregnant ewes were separated into two groups. The study's first group (Group 1) included singleton pregnant ewe (n=20), while the second group (Group 2) included twin pregnant ewe (n=20). Blood samples were collected from the ewes of both study groups at 30th, 45th, 60th, 75th and 90th day of gestation, which were used for PAG and PSBP evaluation along with ultrasonographic examination. Independent samples t-test and repeated measurements ANOVA were used to analyze the data. The correlations between the measures were calculated using Pearson correlation coefficients. Accordingly, a statistically significant difference was observed between single and twin pregnant sheep for all PAG and PSBP measurements at days 30-45-60-75 and 90 (p<0.05). In singleton and twin pregnant ewes, there was a statistically significant difference in PAG and PSBP measurements (p<0.05). In singleton pregnant ewes, a significant positive correlation was found between PAG30 and PSPB30 values (p<0.05), while a significant negative correlation was found between paired measures of PAG45-PSPB90, PAG60-PSPB90, and PAG75-PSPB90 (p<0.05). In conclusion, significant differences in pregnancy protein levels were found in singleton and twin pregnant ewes. It was deduced that knowledge of this difference might give sheep breeders an idea about management factors.

MORPHOLOGICAL PARAMETERS OF SKIN OF PREGNANT EWES OF TUSHIN BREED AT DIFFERENT LEVELS OF FEEDING

Для установления оптимального количества питательных веществ в рационах, необходимого для суягных овцематок, в условиях отгонно-горного содержания Северного Кавказа в 2018 году после окончания случной компании было отобрано 120 маток тушинской породы, идущих на третий окот, которых разделили на четыре группы по 30 голов в каждой. Овцематки контрольной группы получали хозяйственный рацион, составленный в соответствии с нормами ВИЖ (2003 г.). Рацион овцематок второй, третьей и четвертой групп увеличивали по общей питательности соответственно на 10; 15 и 20 %, по сравнению с рационом контрольной группы. Изучение структуры кожи проведено по препаратам, изготовленным из образцов кожи суягных маток, взятых у пяти голов из каждой группы. Установлено, что, в зависимости от сезона года и суягности, кожа подопытных маток претерпела значительные изменения: произошло уменьшение толщины кожи и ее слоев, снизилась активность потовых и сальных желез, уменьшились в размерах волосяные луковицы и диаметр пучков коллагеновых волокон. Наибольшее уменьшение указанных показателей произошло в коже маток, находившихся в суягный период, получавших рацион, составленный согласно нормам ВИЖ (17,1 %). Аналогичные изменения произошли в толщине эпидермиса, пилярного и ретикулярного слоев. Наименьшее снижение толщины кожи и ее слоев произошло у маток, находившихся в условиях высокого уровня кормления. Изучение горизонтальных срезов кожи подопытных групп маток показало, что уровень кормления в суягный период не оказал влияния на количество фолликулов в волосяной группе. У маток, получавших повышенный уровень кормления, количество фолликулов на единице площади кожи уменьшилось на 8,0-13,9 %, что связано с повышением упитанности и, соответственно, с увеличением площади кожи. To establish the optimal amount of nutrients in the diets required for the pregnant sheep, in the conditions of the distant-mountain keeping of the North Caucasus in 2018, after tupping, 120 Tushin ewes were selected for the third lambing, which were divided into four groups 30 heads each. Ewes of the control group received a food ration prepared in accordance with the standards of the All-Russian Research Institute of Animal Husbandry (VIZH) (2003). The ration of the second, third and fourth groups of ewes was increased in total nutritional value by 10%, 15% and 20%, respectively, compared with the diet of the control group. The study of skin structure was carried out using preparations made from pregnant ewe skin samples taken from five heads from each group. It was found that, depending on the season of the year and severity, the skin of the experimental ewes underwent significant changes: the thickness of the skin and its layers decreased, the activity of sweat and sebaceous glands decreased, the hair follicles and the diameter of the collagen fiber bundles decreased in size. The greatest decrease in these parameters occurred in the skin of ewes that were pregnant and received a diet prepared in accordance with the VIZH standards (17.1%). Similar changes occurred in the thickness of the epidermis, pilar and reticular layers. The smallest decrease in the thickness of the skin and its layers occurred in the group of ewes under high feeding conditions. The study of horizontal sections of the skin of the experimental groups of ewes showed that the level of feeding during the lambing period did not affect the number of follicles in the hair group. In the groups of ewes that received an increased level of feeding, the number of follicles per unit of skin area decreased by 8.0-13.9%, which is associated with an increase in body condition and, accordingly, an increase in skin area.

Better expression profile of CD8 and CD4 gene in uterus of pregnant ewe in comparison to non-pregnant - a novel report

CD8 and CD4 T cells play a central role in the immune response to viruses and intracellular pathogens as well as functions for the maintenance of both the mother and fetus. The present study was conducted to explore the differential gene expression profile for CD8 and CD4 present in the uterus with reference to the gravid and non-gravid Garole sheep and confirmation through immuno histochemical studies. Better CD8 and CD4 gene expression was observed in the mid uterus of pregnant ewes compared to that of non-pregnant ewes, where CD8 expression was better to that of CD4. Gene expression profiling of CD8 and CD4 are reported here for the first time in sheep. CD8 and CD4 expression may be regarded as the useful factor for maintenance of pregnancy. The current observations demonstrate that during pregnancy in ewe the immune system may respond to changes in the maternal environment to maintain the size and function of the CD8 and CD4 T-cell compartment. CD8 and CD4 expression may be employed as marker for pregnancy detection in sheep, which remains always a challenge for sheep breeders.

Technical note: Relationship between placentome location and gene expression in bovine pregnancy

A novel, non-terminal surgical procedure to remove a single placentome from the pregnant ewe for gene expression and histological analyses was recently developed in our laboratory. This technique allows for evaluation of nutritional insults on placental development at more than one stage of gestation using a single animal. Early attempts to develop a similar technique in cattle were met with complications due to inaccessibility of the gravid uterine horn because of its location and mass. One alternative is to collect a placentome from the contralateral uterine horn; however, the question remains as to whether gene expression varies among placentomes based on location relative to the fetus. Pregnant heifers were maintained on forage during early gestation and later moved into pens with a Calan gate system (American Calan, Northwood, NH). On gestational day (GD) 158, five heifers were assigned to receive a hay-based diet formulated to meet 100% of NRC requirements, and five heifers were fed 70% of NRC requirements until necropsy on GD244. At necropsy, a single representative placentome was selected for analysis from the antimesometrial side: (1) of the gravid uterine horn central to the amnion, (2) over the allantois immediately adjacent to the amnion, (3) in the tip of the gravid uterine horn, and (4) in the tip of the contralateral uterine horn. Mean placentome weight was greater (P &lt; 0.05) for locations central to the amnion and allantois compared to locations within the tips of the ipsilateral and contralateral horns, respectively. Gene expression for angiogenic factors (FGF2, ODC1, VEGFA, and FLT1), nutrient transporters (SLC7A1 and SLC2A1), and factors associated with hormone action (ESR1, IGF1, IGFBP3, CSH1, and PAG1) were unaffected (P &gt; 0.05) by dietary treatment or location of the placentome. Results indicate that location of the placentome in relation to the fetus does not impact gene expression, enhancing the efficacy of nonterminal methodologies for sampling gene expression in placentomes.