The investigation of the effects of vitamin A, vitamin E, and ß-carotene plus vitamin E on some fertility parameters in ewes.

This study was aimed at investigating the effects of vitamin A (VITA), vitamin E (VITE), and combined ß-carotene plus vitamin E (ßCAR+VITE) injections on some fertility parameters in ewes. Estrus synchronization was performed by treating the ewes with intravaginal FGA sponges impregnated with 30 mg of fluorogestone acetate. On the days of the insertion and withdrawal of the intravaginal sponges, groups VITA, VITE, and ßCAR+VITE were administered with 500 000 IU of vitamin A, 50 mg of vitamin E, and a combination of ß-carotene plus vitamin E, respectively. The ewes in the control group (C) were maintained for control purposes. Statistically significant differences were determined between groups VITA and ßCAR+VITE, groups VITE and ßCAR+VITE, and groups C and ßCAR+VITE, as well as groups VITE and C, groups VITA and C for the multiple birth rates. While significant differences were determined between groups VITA and C, groups VITE and C, and groups ßCAR+VITE and C for the lambing rates, it was ascertained that the ratio of newborn lambs to delivered ewes (litter size) significantly differed between groups VITA and ßCAR+VITE, groups VITA and C, groups VITE and ßCAR+VITE, groups VITE and C, and groups ßCAR+VITE and C. The highest MDA level and lowest GSH level were determined on day 20 after mating in the control group. In conclusion, it is suggested that both multiple birth rates and litter size can be increased by the combined administration of ß-carotene and vitamin E.

miR136 regulates proliferation and differentiation of small tail han sheep preadipocytes.

Low meat performance is the defect of Small Tail Han sheep. Intramuscular fat affects meat quality and largely determined by adipogenesis. In previous study, miR136 was showed one of differentially expressed microRNAs between preadipocytes and mature adipocytes of Small Tail Han sheep but its role in adipogenesis is still not elucidated. Here, we investigated the effect of miR136 on adipogenesis and the underlying mechanism. qPCR data showed that miR136 level increased with preadipocytes proliferation while declined with preadipocytes differentiation. Moreover, miR136 mimics blocked lipid droplet formation, reduced lipid content and triglyceride accumulation while miR136 inhibitor showed the opposite effects, revealing that miR136 promoted preadipocytes proliferation but inhibited preadipocytes differentiation. Bioinformatics and biochemical validation manifested that PPARGC1B was a target of miR136. Furthermore, miR136 mimics decreased PPARγ and C/EBPα expression accompanied by PPARGC1B expression descending. Reverse effects were observed with miR136 inhibitor. Besides, overexpression of miR136 elevated IGF1 expression. Collectively, our data first exhibited a regulatory role of miR136 in adipogenesis, which is promoting preadipocytes proliferation through elevating IGF1 expression while inhibiting preadipocytes differentiation through targeting PPARGC1B and further declined PPARγ and C/EBPα expression. The modulation of PPARGC1B by miR136 may provide a new potential target for increasing intramuscular fat.

Differences in ingestive behavior between grazing goats and sheep at the bite scale.

This study aimed to clarify the differences in ingestive behavior between goats and sheep at the bite scale. Animals were allowed to graze a feeding station of bahiagrass (Paspalum notatum Flügge) with two sward heights (short and tall) to two levels of bite depletion (20 and 40 bites). Ingestive behavior variables, which represent the rate and mass of bites and chews, intake rate, bite dimensions, and bite placement characteristics, were quantified. The interspecies difference in ingestive behavior became obvious at the short sward. Goats reduced the inter-bite distance and maintained bite overlapping but took deeper bites than sheep at the short sward, resulting in slightly greater bite mass. These behavioral changes with efficient chewing may be helpful to maintain the intake rate at the short sward. Sheep maintained their inter-bite distance regardless of the sward height and decreased overlapping bites at the short sward. These behavioral characteristics in sheep in response to sward height may partly compensate for the decrease in the bite mass at the short sward, although it may not always maintain the intake rate. Thus, the present study suggests that goats and sheep implement different bite scale ingestive behaviors, including bite placement, when they eat short swards.

Molecular characterization and expression of TGFßRI and TGFßRII and its association with litter size in Tibetan sheep.

BACKGROUNDS: Transforming growth factor-ß (TGF-ß) type I receptor (TGFßRI) and type II receptor (TGFßRII) are the members of the TGFß superfamily, which are potent regulators of cell proliferation and differentiation in many organ systems, and they play key roles in multiple aspects of follicle development. OBJECTIVES: We aimed to explore the characterization, expression analysis of TGFßRI and TGFßRII genes, and the association with litter size in Tibetan sheep. METHODS: In this study, we cloned the complete coding sequences of TGFßRI and TGFßRII genes in Tibetan sheep and analyzed their genomic structures. RESULTS: The results showed that percentages of sequences homology of the two proteins in Tibetan sheep were the most similar to Ovis aries (100%), followed by Bos mutus (99%). The RT-qPCR showed that two genes were expressed widely in the different tissues of Tibetan sheep. The TGFßRI expression was the highest in the lung (p < 0.05), followed by the spleen and ovary (p < 0.05). The TGFßRII expression was significantly higher in uterus than that in lung and ovary (p < 0.05). In addition, the χ2 test indicated that all ewes in the population were in Hardy-Weinberg equilibrium, and the population was in medium or low polymorphic information content status. We also found four Single Nucleotide Polymorphism (SNPs), g.9414A > G, g.28881A > G, g.28809T > C, g.10429G > A in sheep TGFßRI gene and g.63940C > T, g.63976C > T, g.64538C > T, g.64504T > A in TGFßRII gene. Three genotypes, except for g.64504T > A, and three haplotypes were identified in each gene. linkage disequilibrium analysis indicated that there was strong linkage disequilibrium in each gene. The association analysis showed that the four SNPs of TGFßRI were associated with litter size (p < 0.05), and g.63940C > T of TGFßRII was confirmed to be associated with litter size (p < 0.05). CONCLUSIONS: Based on these preliminary results, we can assume that TGFß receptors (TGFßRI and TGFßRII) may play an important role in sheep reproduction.

Efeito do cilostazol na produção in vitro de ovinos / Effect of cilostazol on in vitro production of sheep / Efecto del cilostazol en la producción in vitro de ovejas

O objetivo deste estudo foi avaliar o efeito da inclusão de cilostazol no meio de maturação in vitro de oócitos sobre produção in vitro de embriões ovinos. Para isso, foram realizadas colheitas de oócitos oriundos de ovários obtidos em abatedouro por meio do método de aspiração folicular com bomba de vácuo. Os oócitos foram divididos em quatro grupos de maturação: grupo CON, onde os complexos cumulus oócitos foram imersos em TCM-199, suplementado com 500 UI de penicilina, 0,5 mg de estreptomicina, 1,25 µg de anfotericina, 0,2 mM de piruvato de sódio, 10% (v/v) de soro fetal bovino (SFB), 10 ng/mL de fator de crescimento epidérmico (EGF), 10 ug/m de FSH, 10 µg/mL de LH, 10 ug/mL de estradiol e 100 µM de cisteamina; e nos grupos CILO0,3; CILO1 e CILO10, os oócitos foram maturados no meio do grupo CON, mas sem a adição de cisteamina e suplementado com as concentrações de 0,3; 1 e 10 µM, respectivamente. Após 24h, os oócitos foram avaliados quanto a presença ou não de células do cumulus e quanto ao grau de expansão e destinados à fecundação in vitro, em meio FIV, juntamente com espermatozoides. Após a FIV, os presumíveis zigotos seguiram para o cultivo in vitro. Foram avaliadas clivagens no dia 2, sendo dia 0 o dia do início do CIV. Os resultados foram expressos em porcentagem e as variáveis de expansão das células do cumulus e número de estruturas clivadas foram comparadas por meio do teste qui-quadrado do software Epi Info (Epi Info 7.2.5, Atlanta, GA, EUA, 2021). Os resultados foram considerados significativos quando P<0,05. Em relação à expansão das células do cumulus, todos os grupos apresentaram 100% de expansão. Não houve diferenças significativas quanto ao grau de expansão das células do cumulus entre os grupos suplementados com cilostazol e cisteamina (P>0,05), assim como não houve diferenças significativas entre as taxas de clivagem entre os grupos suplementados com cilostazol e cisteamina (P > 0,05).

The objective of this study was to evaluate the effect of including cilostazol in the in vitro maturation medium of oocytes on the in vitro production of sheep embryos. Oocytes were collected from ovaries obtained from a slaughterhouse by follicular aspiration with a vacum pump. The oocytes were divided into four maturation groups: the CON group, where the cumulus-oocyte complexes were immersed in TCM-199 supplemented with 500 IU of penicillin, 0.5 mg of streptomycin, 1.25 µg of amphotericin, 0.2 mM of sodium pyruvate, 10% (v/v) fetal bovine serum (FBS), 10 ng/mL of epidermal growth factor (EGF), 10 µg/mL of FSH, 10 µg/mL of LH, 10 µg/mL of estradiol, and 100 µM of cysteamine; and in the CILO0.3, CILO1, and CILO10 groups, the oocytes were matured in the CON group medium without the addition of cysteamine and supplemented with concentrations of 0.3, 1, and 10 µM of cilostazol, respectively. After 24 hours, the oocytes were evaluated for the presence or absence of cumulus cells and the degree of expansion and then subjected to in vitro fertilization (IVF) with sperm in FIV medium. After IVF, the presumptive zygotes were cultured in vitro. Cleavage was evaluated on day 2, with day 0 being the start of IVF. Results were expressed as a percentage, and variables such as cumulus cell expansion and the number of cleaved structures were compared using the chi-square test in the Epi Info software (Epi Info 7.2.5, Atlanta, GA, USA, 2021). Results were considered significant when P < 0.05. All groups showed 100% cumulus cell expansion, and there were no significant differences in cumulus cell expansion degree between the cilostazol- and cysteamine-supplemented groups (P > 0.05), as well as no significant differences in cleavage rates between the cilostazol- and cysteamine-supplemented groups (P > 0.05).

El objetivo de este estudio fue evaluar el efecto de la inclusión de cilostazol en el medio de maduración in vitro de ovocitos sobre la producción in vitro de embriones ovinos. Para ello, se realizaron recolecciones de ovocitos provenientes de ovarios obtenidos en un matadero mediante el método de aspiración folicular con bomba de vacío. Los ovocitos se dividieron em cuatro grupos de maduración: grupo CON, donde los complejos cúmulus ovocitos se sumergieron en TCM-199, suplementado con 500 UI de penicilina, 0,5 mg de estreptomicina, 1,25 ug de anfotericina, 0,2 mM de piruvato de sodio, 10% (v/v) de suero fetal bovino (SFB), 10 ng/mL de factor de crecimiento epidérmico (EGF), 10 ug/m de FSH, 10 µg/mL de LH, 10 µg/mL de estradiol y 100 µM de cisteamina; y en los grupos CILO0,3; CILO1 y CILO10, los ovocitos se maduraron en el medio del grupo CON, pero sin la adición de cisteamina y suplementado con las concentraciones de 0,3; 1 y 10 µM, respectivamente. Después de 24 horas, los ovocitos se evaluaron en cuanto a la presencia o no de células del cúmulus y em cuanto al grado de expansión y se destinaron a la fecundación in vitro, en medio FIV, junto con espermatozoides. Después de la FIV, los presuntos cigotos siguieron para el cultivo in vitro. Se evaluaron las clivajes en el día 2, siendo el día 0 el día del início del CIV. Los resultados se expresaron en porcentaje y las variables de expansión de las células del cúmulos y número de estructuras clivadas se compararon mediante la prueba del chi-cuadrado del software Epi Info (Epi Info 7.2.5, Atlanta, GA, EE. UU., 2021). Los resultados se consideraron significativos cuando P < 0,05. En relación a la expansión de las células del cúmulus, todos los grupos presentaron el 100% de expansión. No hubo diferencias significativas en cuanto al grado de expansión de las células del cúmulus entre los grupos suplementados con cilostazol y cisteamina (P > 0.05), así como no hubo diferencias significativas entre las tasas de clivaje entre los grupos suplementados con cilostazol y cisteamina (P>0,05).

Effect of weaning and feed provision times on the performance and several behavioural traits of post-weaning lambs.

The aim of the present study was to assess if weaning time (morning or evening) and feed provision (immediate or 4 h delayed) can influence growth performance and expression of juvenile lamb behaviour immediately after and at the age of 50-125 days old. Forty lambs were randomly assigned to 4 groups: E1 (evening + immediate), E2 (evening + delayed), M1 (morning + immediate) and M2 (morning + delayed). All lambs were especially active during the first hour after weaning. However, their activity within the first 24 h after weaning was mainly affected by their circadian rhythms, since lambs were more active during the day compared to night. On the other hand, no effect of alfalfa hay provision on lamb activity during these first 24 h was observed. At the age of 50-125 days old, body weight was measured, and an isolation and flight distance test was implemented. There were no significant differences among lambs in body weight, number of jumps and heart rates assessed during isolation test and flight distance. However, the number of vocalizations was lower (65-110th day, P < 0.05) for the E2 compared to E1 lambs. Breed also slightly affected (95th day, P < 0.05) the average heart rate of lambs, with greater values for Karagouniko compared to Chios lambs. It is concluded that no discernible effects of weaning or feeding time were observed on growth performance and the display of stress-induced behavioural components of juvenile lambs till the age of 125 days old.

Rumen fermentation and epithelial gene expression responses to diet ingredients designed to differ in ruminally degradable protein and fiber supplies.

Although numerous studies exist relating ruminal volatile fatty acid (VFA) concentrations to diet composition and animal performance, minimal information is available describing how VFA dynamics respond to diets within the context of the whole rumen environment. The objective of this study was to characterize how protein and fiber sources affect dry matter intake, rumen pH, fluid dynamics, fermentation parameters, and epithelial gene expression. Four diet treatments (soybean meal or heat-treated soybean meal and beet pulp or timothy hay) were delivered to 10 wethers. The soybean meals served as crude protein (CP) sources while the beet pulp and timothy hay represented neutral detergent fiber (NDF) sources. Feed intake, rumen pH, fluid pool size, and fluid passage rate were unaffected by treatment. Butyrate synthesis and absorption were greater on the beet pulp treatment whereas synthesis and absorption of other VFA remained unchanged. Both CP and NDF treatment effects were associated with numerous VFA interconversions. Expression levels of rumen epithelial genes were not altered by diet treatment. These results indicate that rumen VFA dynamics are altered by changes in dietary sources of nutrients but that intake, rumen environmental parameters, and the rumen epithelium may be less responsive to such changes.

Smad4 mediates Bmf involvement in sheep granulosa cell apoptosis.

Bcl-2-modifying factor (Bmf) functions to mediate follicular atresia and oocyte growth in mice. It has been proven that TGF-ß can induce Bmf expression via the Smad4 pathway in a variety of cells, and then induce cell apoptosis. Based on this, we hypothesized that Smad4 and Bmf may play important roles in the apoptosis of granulosa cells (GCs) in domestic animals. This study used small-tailed Han sheep follicular GCs cultured in vitro as a model system, and overexpression or interference experiments, to explore the biological roles of Bmf and reveal the preliminary regulatory mechanisms between Smad4 and Bmf in the process of GCs' apoptosis. We found that the proliferation rate of sheep GCs was significantly increased after the knockdown of Bmf, whereas overexpressing Bmf increased the apoptosis rate of GCs, results also verified by the expression patterns of PCNA, Bcl-2, and Bax genes. After the Smad4 knockdown, the apoptosis rate of GCs was increased, while the mRNA and protein expression of Bmf was significantly up-regulated. A rescue experiment verified that the Bmf knockdown could alleviate GCs' apoptosis induced by Smad4 knockdown. In conclusion, our study not only elucidated an important role for Bmf in the apoptosis of sheep GCs but also revealed a new regulatory pathway between Smad4 and Bmf in this process.

Expanding or shrinking? range shifts in wild ungulates under climate change in Pamir-Karakoram mountains, Pakistan.

Climate change is expected to impact a large number of organisms in many ecosystems, including several threatened mammals. A better understanding of climate impacts on species can make conservation efforts more effective. The Himalayan ibex (Capra ibex sibirica) and blue sheep (Pseudois nayaur) are economically important wild ungulates in northern Pakistan because they are sought-after hunting trophies. However, both species are threatened due to several human-induced factors, and these factors are expected to aggravate under changing climate in the High Himalayas. In this study, we investigated populations of ibex and blue sheep in the Pamir-Karakoram mountains in order to (i) update and validate their geographical distributions through empirical data; (ii) understand range shifts under climate change scenarios; and (iii) predict future habitats to aid long-term conservation planning. Presence records of target species were collected through camera trapping and sightings in the field. We constructed Maximum Entropy (MaxEnt) model on presence record and six key climatic variables to predict the current and future distributions of ibex and blue sheep. Two representative concentration pathways (4.5 and 8.5) and two-time projections (2050 and 2070) were used for future range predictions. Our results indicated that ca. 37% and 9% of the total study area (Gilgit-Baltistan) was suitable under current climatic conditions for Himalayan ibex and blue sheep, respectively. Annual mean precipitation was a key determinant of suitable habitat for both ungulate species. Under changing climate scenarios, both species will lose a significant part of their habitats, particularly in the Himalayan and Hindu Kush ranges. The Pamir-Karakoram ranges will serve as climate refugia for both species. This area shall remain focus of future conservation efforts to protect Pakistan's mountain ungulates.

Antioxidant capacity, reproductive response and glucose concentration and insulin of ewes supplemented prior to insemination with orange residue / [Capacidade antioxidante, resposta reprodutiva e concentração de glicose e insulina de ovelhas suplementadas antes da inseminação com resíduo de laranja]

The objective was to evaluate the antioxidant capacity, glucose and insulin concentration and reproductive performance of ewes supplemented with orange residue prior to insemination. Fifty-five multiparous ewes were divided into two corrals, and 15 unbred ewes were kept individually to measure feed consumption. Two integral diets were administered; T0: control treatment and T1: with 20% of dry matter of orange residue. Ten days after the start of supplementation, the ewes were synchronized. Supplementation was finalized prior to artificial insemination, then, a blood sample was taken to measure the antioxidant capacity and glucose and insulin concentration. An analysis of variance was made to evaluate the effect of treatment on the antioxidant capacity, glucose and insulin; and to analyze the response to estrus, percentage of gestation and prolificity a ji squared test was performed. Of 9 antioxidant compounds found in the orange residue, hesperidin (7.44%), chlorogenic acid (0.50%) and protocatechuic acid had the highest concentration. Feed intake, estrus response, percentage of gestation, antioxidant capacity, and glucose and insulin concentration were not affected by the treatment. It is concluded that inclusion of 20% of orange residue in the diet prior to insemination in ewes is possible.(AU)

O objetivo deste estudo foi avaliar a capacidade antioxidante, a concentração de glicose e insulina e o comportamento reprodutivo de ovelhas suplementadas com resíduo de laranja antes da inseminação. Cinquenta e cinco ovelhas multíparas foram divididas em dois currais e 15 ovelhas sem raça foram mantidas individualmente para se medir o consumo de ração. Duas dietas integrais foram administradas; T0: tratamento controle e T1: dieta com 20% de resíduo de laranja seco. Dias após o início da suplementação, as ovelhas foram sincronizadas. A suplementação foi finalizada antes da inseminação artificial e, em seguida, foi coletada uma amostra de sangue para medir a capacidade antioxidante e a concentração de glicose e insulina. Uma análise de variância foi feita para avaliar o efeito do tratamento sobre a capacidade antioxidante, a glicose e a insulina, e um teste do ji quadrado foi realizado para analisar a resposta ao estro, a porcentagem de gestação e de prolificidade. Dos nove compostos antioxidantes encontrados no resíduo laranja, a hesperidina (7,44%), o ácido clorogênico (0,50%) e o ácido protocatecuico foram os de maior concentração. O consumo alimentar, a resposta ao estro, a porcentagem de gestação, a capacidade antioxidante, a concentração de glicose e a insulina não foram afetados pelo tratamento. Conclui-se que é possível a inclusão de 20% de resíduos de laranja na dieta antes da inseminação em ovelhas.(AU)

Promoting viable twin birth on single-bearing ewes in the Arabian Gulf region: reproductive, nutritional, and economic perspectives.

Raising sheep and goats in the gulf region is a large entrepreneurial business. This is, of course, derived from the big demands of lamb and goat meats for citizens and expatriates. There is a major population living in the rural desert areas whose main income steps from rising local sheep and goats. Despite large number of farmers into sheep production, the country still imports from foreign countries to meet augment local demand. Thus, improving local sheep production is a means to reduce the importation of sheep from foreign land. The low twinning rates in the main two indigenous breeds (i.e., Najdi and Noemi) in the region motivated the researchers to pursue an avenue for maximizing the neonatal outcomes is a contributing factor to low level of sheep proliferation in the region. Thus, pursuing an avenue for maximizing the neonatal outcome per female is a good strategy. Application of hormonal induction protocol support reproductive efficiency by improving viable twin birth in single-bearing ewes. By applying this method, several sheep raisers could retain their business more effectively.

Local adaptations of Mediterranean sheep and goats through an integrative approach.

Small ruminants are suited to a wide variety of habitats and thus represent promising study models for identifying genes underlying adaptations. Here, we considered local Mediterranean breeds of goats (n = 17) and sheep (n = 25) from Italy, France and Spain. Based on historical archives, we selected the breeds potentially most linked to a territory and defined their original cradle (i.e., the geographical area in which the breed has emerged), including transhumant pastoral areas. We then used the programs PCAdapt and LFMM to identify signatures of artificial and environmental selection. Considering cradles instead of current GPS coordinates resulted in a greater number of signatures identified by the LFMM analysis. The results, combined with a systematic literature review, revealed a set of genes with potentially key adaptive roles in relation to the gradient of aridity and altitude. Some of these genes have been previously implicated in lipid metabolism (SUCLG2, BMP2), hypoxia stress/lung function (BMPR2), seasonal patterns (SOX2, DPH6) or neuronal function (TRPC4, TRPC6). Selection signatures involving the PCDH9 and KLH1 genes, as well as NBEA/NBEAL1, were identified in both species and thus could play an important adaptive role.

Evaluation of homeothermy, acid-base and electrolytic balance of black goats and ewes in an equatorial semi-arid environment.

The aim of this study was to investigate the influence of environmental conditions and species on thermoregulatory responses, acid-base and electrolyte balance of black goats and ewes in an equatorial semi-arid environment. Ten Canindé goats and seven Morada Nova ewes with black coat color, all multiparous, aged between 2 and 3 years, non-lactating, non-pregnant, and body weight (BW) of 22.84 ± 4.17 kg for goats and 22.60 ± 3.18 kg for ewes were used in this study. Air temperature (AT) and relative humidity (RH) were measured. Respiratory rate (RR), Rectal temperature (RT), sweating rate (SR), hydrogen potential (pH), partial pressure of carbon dioxide (PCO2), venous oxygen pressure (PO2), bicarbonate (HCO3), base excess (BE), total carbon dioxide concentration (TCO2), venous oxygen saturation (SO2), sodium (Na+) and potassium (K+) were recorded. Animal species (caprine and ovine) and environmental conditions (Thermoneutral condition, TC and Heat condition, HC) were considered as fixed effects. Univariate and multivariate analysis techniques were used. Differences were observed between the two environmental conditions. Significant changes in all thermoregulatory responses for goats and ewes were observed according to the environmental condition effect. The general means of the species showed that only SR was high in ewes (P < 0.05), following a reverse change when compared to goat SR. For the environmental condition effect, only the blood pH of goats did not change under HC (P < 0.05), while the BE and TCO2 did not change for ewes. The general means of PCO2, HCO3, BE, TCO2 and SO2 were higher in ewes compared to goats. For electrolytic balance, Na + demonstrated elevations in HC. Brazilian black goats and ewes raised in an equatorial semi-arid environment tend to have particular homeothermy, acid-base and electrolytic balance which mostly depend on the environmental conditions they are raised. The results support the changes in physiological mechanisms between black goats and ewes; however, both are locally adapted.

Scrotal subcutaneous temperature is increased by scrotal insulation or whole-body heating, but not by scrotal neck insulation; however, all three heat-stress models decrease sperm quality in bulls and rams.

Ruminant testes are ~2-6 °C below body temperature; increased testicular temperature reduces sperm motility and morphology. Our objective was to serially monitor scrotal subcutaneous temperatures during testicular heat stress and relate those to sperm quality. Two experiments were conducted, with temperature sensors surgically implanted in scrotal subcutaneous tissues recording temperatures every 15 min and semen collected and evaluated weekly. After an initial control interval, testicular temperature was increased. In Experiment 1, in two Angus bulls, whole-scrotum insulation for 96 h increased scrotal subcutaneous temperatures by ~2.0-2.5 °C (P < 0.05). Total and progressive motility decreased (P < 0.05) and reached a nadir at Week 3 (~20 and 10%, respectively). Furthermore, morphologically normal sperm and acrosome integrity also decreased significantly, reaching nadirs at Weeks 3 (15%) and 4 (34%). In Experiment 2, 10 Dorset rams were allocated randomly into two equal groups and either: 1) exposed to 28 °C ambient temperature and 30-34% RH for 8 h/d for 4 d; or 2) subjected to scrotal neck insulation that was applied and removed at the same time as the start and completion, respectively, of heat exposures in the other rams. Scrotal subcutaneous temperatures (monitored in three rams per group) were increased in response to whole-body heating (~0.8 °C, P < 0.05), but not significantly changed by scrotal neck insulation. Decreases in sperm quality were generally similar between treatments, with the most profound changes evident 4 wk after heat stress, with ~10 percentage point reductions in both total and progressive motility and ~10 and 20 percentage point decreases in morphologically normal sperm in rams with whole-body heating versus scrotal neck insulation, respectively. In conclusion, scrotal subcutaneous temperature was significantly increased by scrotal insulation or whole-body heating, but not by scrotal neck insulation; however, all three heat-stress models decreased sperm motility and morphology in bulls and rams.

Cooled storage of semen from livestock animals (Part II): Camelids, goats, and sheep.

This review is part of the Festschrift in honor of Dr. Duane Garner and provides an overview of current techniques in cooled storage of semen from livestock animals such as camelids, goats, and sheep. Facing worldwide environmental changes and a trend towards more conscious and healthy eating behaviors, the development of a stable animal breeding industry is a significant challenge for the near future. In the present review, factors influencing semen handling in camelids, goats and sheep are described and relevant methods as well as current trends to improve liquid-storage of cooled semen are discussed, including extenders, additives, cooling rates, and storage temperatures. The species-specific physiology and resulting challenges are taken into consideration. While the main problem for camelid semen processing is the relatively greater viscosity as compared with that of some other animals, the deciding factor for successful artificial insemination (AI) in goats and sheep is the site (i.e., cervical or vaginal) of semen placement in the reproductive tract. Due to the type of cervical anatomy, the penetration of the cervix when using AI instruments is rather difficult. Furthermore, the seminal plasma of small ruminants affects the interaction with milk-based extenders and egg yolk which results in species-specific regimens for cooled liquid-preservation. Comparing all three species, the greatest pregnancy rates were obtained by AI with goat semen after cooled liquid-storage for several days.

Functional aspects of the Eustachian tube by means of 3D-modeling.

The extent of dysfunction of the Eustachian tube (ET) is relevant in understanding the pathogenesis of secondary otological diseases such as acute or chronic otitis media. The underlying mechanism of ET dysfunction remains poorly understood except for an apparent genesis such as a nasopharyngeal tumor or cleft palate. To better describe the ET, its functional anatomy, and the biomechanical valve mechanism and subsequent development of diagnostic and interventional tools, a three-dimensional model based on thin-layer histology was created from an ET in this study. Blackface sheep was chosen as a donor. The 3-D model was generated by the coherent alignment of the sections. It was then compared with the cone-beam computed tomography dataset of the complete embedded specimen taken before slicing. The model shows the topographic relation of the individual components, such as the bone and cartilage, the muscles and connective tissue, as well as the lining epithelium with the lumen. It indicates a limited spiraling rotation of the cartilaginous tube over its length and relevant positional relationships of the tensor and levator veli palatine muscles.

Use of ammonium chloride to prevent urolithiasis in sheep / [Utilização do cloreto de amônio na prevenção de urolitíase em ovinos]

Urolithiasis has a high incidence among confined sheep. It is multifactorial and may cause economic damage. Our aim was to determine the capacity of urinary acidification using ammonium chloride in sheep. Twenty-five 3-month-old male sheep were confined and randomly divided into three groups; the G200 and G500 groups received 200mg/kg/GW and 500mg/kg/GW of ammonium chloride daily for 56 consecutive days, respectively, whereas the CG group did not receive ammonium chloride. Sampling times and clinical evaluation were performed weekly, starting from the 14th day of confinement (M1 or immediately before administering ammonium chloride) until the 17th day (M9) of the feedlot. Hemogasometry, biochemical examination of serum urea and creatinine concentration and ultrasound evaluation of the urinary tract were performed. The urinalysis indicated a higher incidence of ammonium magnesium phosphate crystals at the beginning of the study, showing a migration to urate crystal formation, mainly in the G500 group because of urinary acidification. No hemogasometric, serum biochemistry, ruminal fluid, or ultrasonographic changes were observed. Urinary acidification was achieved and maintained after M7 during the administration of ammonium chloride in the G500 group, but not in the other study groups.(AU)

A urolitíase apresenta alta incidência em ovinos confinados, etiologia multifatorial, e pode causar prejuízo econômico. O objetivo do presente estudo foi determinar a capacidade da acidificação urinária mediante o uso de cloreto de amônio em ovinos. Foram utilizados 25 ovinos de três meses de idade, confinados e divididos aleatoriamente em três grupos: grupo CG (controle) não recebeu cloreto de amônio; grupo G200 (200mg/kg/PV) recebeu cloreto de amônio por 56 dias consecutivos; grupo G500 (500mg/kg/PV) recebeu cloreto de amônio por 56 dias consecutivos, administrados diariamente por via oral. Os momentos (M) de colheita de amostras e de avaliação clínica foram realizados com intervalo de sete dias, sendo M1 (imediatamente antes do cloreto de amônio), M2 (sete dias após) até M9, totalizando 70 dias de confinamento. Foram realizadas hemogasometria, concentração sérica de ureia e creatinina e avaliação ultrassonográfica do trato urinário. Na urinálise, houve uma maior incidência de cristais de fosfato amônio magnesiano no início do estudo, com migração para formação de cristais de urato, principalmente no G500, devido à acidificação urinária. Não houve alterações hemogasométricas, na bioquímica sérica, no líquido ruminal, ou alterações ultrassonográficas. A acidificação urinária foi obtida e mantida a partir do M7 durante a administração do cloreto de amônio no grupo G500, não ocorrendo nos outros grupos de estudo.(AU)

Maternal caffeine administration to ewes does not affect perinatal lamb survival.

Perinatal mortality of lambs is the major source of reproductive loss in extensive sheep production systems. Treatment with caffeine has reduced intra-partum mortality and/or improved metabolic indicators in other species following hypoxia. This study was conducted to evaluate the efficacy of caffeine for improving perinatal lamb survival. Experiment 1 comprised group-fed Merino ewes grazing pasture and offered 1.8 g/day (estimated 20 mg/kg live weight) caffeine throughout a 4-week lambing period, and a control without caffeine. The survival of lambs to marking (vaccinated, tail docked, males castrated) age in the caffeine treatment group (0.81) did not differ (P = 0.199) from that of control lambs (0.73; total born n = 877). Experiment 2 comprised Merino ewes lambing from three successive weekly joining groups. Treated ewes were drenched with an aqueous caffeine solution at a dose rate of 10 mg/kg live weight from the day before anticipated lambing, until the individual lambed. Control ewes were drenched with water. The proportion of lambs born dead (0.07) and the survival of lambs to marking age (caffeine 0.61; control 0.62) were similar between treatment groups (total born n = 1158). In both experiments, ewe mortality and the weight of lambs at marking were not altered by caffeine treatments. The results from this large-scale field study indicate caffeine is not an effective therapeutic agent to increase either intra-partum or perinatal survival, or lamb growth rates.

Singleton or twin male lambs: Effects on their reproductive development.

Because intrauterine environment differs between twins and singletons, twin-born lambs are often studied when effects of fetal programming are evaluated. In sheep, fetal programming might have effects on reproductive physiology and behavior after sexual maturation. The aim of this study was to compare sperm output and sexual behavior in developing singleton- or twin-born lambs of similar body weight. Singleton lambs (n = 12) and twin (n = 9) male-male lambs were used. From 5.4 until 9.1 months of age, body weight, scrotal circumference (every 3-4 weeks), sexual behavior (every 14 days) and semen characteristics (every 28 days) were evaluated. In the third ejaculate, singleton lambs ejaculated a larger volume of semen than twins (P = 0.03). Considering a pool of the three ejaculates, twin lambs ejaculated semen with a greater sperm concentration than singleton lambs (P = 0.015). There was an interaction between group and time to the onset of courtship behavior (P = 0.02) and a tendency for an interaction in the number of mount attempts (P = 0.052). Singleton-born lambs, during the first evaluation period began courtship behavior earlier than twin-born lambs (P < 0.0001). In conclusion, there were only slight differences in semen and sexual behavior between male ram lambs born as singletons or twins with similar weight. Male ram lambs born as singletons initiated the courtship behavior earlier than twins during the first sexual behavioral evaluation period, ejaculated a larger volume of semen in the third consecutive ejaculate, and there was a lesser sperm concentration in the three ejaculates.

Macromineral and trace element requirements for Santa Ines sheep.

Minerals play an important role in animal metabolism. Knowledge of mineral requirements allows well-formulated diets to be provided, which is the main factor that affects performance. To determine the macromineral and trace element requirements for growth and maintenance, thirty-eight 2-month-old Santa Ines lambs with initial body weight (BW) of 13.0 ± 1.49 kg were distributed in a factorial design with feeding levels (ad libitum, 30% and 60% feed restriction) and sex classes [castrated (CM) and intact males (IM)]. The net mineral requirements for gain were higher (P < 0.05) with increasing BW and average daily gain, except for Ca and Na, which remained constant as the empty BW (EBW) increased. The macromineral net requirement for maintenance (g/kg EBW0.75) and the true retention coefficient (k; %) were 0.0784 and 65.2 for Ca, 0.0926 and 80.0 for P, and 0.0379 and 59.0 for K, respectively. The k of Mg was higher (P < 0.05) for IM (11.3 for IM and 7.9 for CM). Sex did not affect (P > 0.05) the maintenance requirement of the trace elements Co, Cu, Zn and Cr which were 0.0015, 0.037, 0.698, and 0.0055 (mg/kg EBW0.75), respectively. Our study indicated that the Santa Ines net mineral requirements are different from the main nutritional requirements established by committees for sheep, which may result in unbalanced diets.