Rate In Sheep Research Articles

Simultaneous, Non-Contact and Motion-Based Monitoring of Respiratory Rate in Sheep Under Experimental Condition Using Visible and Near-Infrared Videos

The validation of methods for understanding the effects of many diseases and treatments requires the use of animal models in translational research. In this context, sheep have been employed extensively in scientific studies. However, the imposition of experimental conditions upon these animals may result in the experience of discomfort, pain, and stress. The ethical debates surrounding the use of animals in research have resulted in the adoption of Directive 2010/63/EU. The present study proposes a non-contact method for monitoring the respiration rate of sheep based on video processing. The Detecron2 model was trained to segment the sheep’s body, abdominal, and facial regions in the video frames. A motion-tracking algorithm was developed to assess abdominal movement associated with the sheep’s respiratory cycle. The method was applied to videos of Rhön sheep under experimental and housing conditions, utilising two types of cameras to assess the effectiveness of the proposed approach. The mean average error (MAE) obtained was 0.79 breaths/minute for the visible and 1.83 breaths/minute for the near-infrared (NIR) method. This study demonstrates the feasibility of video technology for simultaneous and non-invasive respiration monitoring, being a crucial parameter for assessing the health deterioration of multiple laboratory animals.

Hydrogel coating containing heparin and cyclodextrin/paclitaxel inclusion complex for retrievable vena cava filter towards high biocompatibility and easy removal

Aiming to improve the retrieval rate of retrievable vena cava filters (RVCF) and extend its dwelling time in vivo, a novel hydrogel coating loaded with 10 mg/mL heparin and 30 mg/mL cyclodextrin/paclitaxel (PTX) inclusion complex (IC) was prepared. The drug-release behavior in the phosphate buffer solution demonstrated both heparin and PTX could be sustainably released over approximately two weeks. Furthermore, it was shown that the hydrogel-coated RVCF (HRVCF) with 10 mg/mL heparin and 30 mg/mL PTX IC effectively extended the blood clotting time to above the detection limit and inhibited EA.hy926 and CCC-SMC-1 cells' proliferation in vitro compared to the commercially available bare RVCF. Both the HRVCF and the bare RVCF were implanted into the vena cava of sheep and retrieved at at 2nd and 4th week after implantation, revealing that the HRVCF had a significantly higher retrieval rate of 67 % than the bare RVCF (0 %) at 4th week. Comprehensive analyses, including histological, immunohistological, and immunofluorescent assessments of the explanted veins demonstrated the HRVCF exhibited anti-hyperplasia and anticoagulation properties in vivo, attributable to the hydrogel coating, thereby improving the retrieval rate in sheep. Consequently, the as-prepared HRVCF shows promising potential for clinical application to enhance the retrieval rates of RVCFs.

Modeling the economic performance of small ruminant pastoralist flocks and financial impact of changes in reproductive performance and mortalities in Kajiado county, Kenya

This study investigated the economic performance of pastoralist small ruminant flocks in Kajiado county, Kenya, and the financial impact of mortalities and changes in performance indicators. A survey of 129 pastoralist small ruminant flocks captured production and economic data for a 12-month period via interview. Simulation models were then developed for flocks with different performance levels and trading activities. Their gross margins, and the financial impact from mortalities, were estimated. Sensitivity analyses were conducted for select performance indicators to assess their relative economic importance. On average, pastoralists who were not purchasing supplementary feed (79% of flocks) had gross margins of KSh 3,016 – KSh 3,123 per reproductive female. Goat production generated 2.43–2.51 times greater returns than sheep production. High efficiency mixed flocks achieved 2.04–2.06 times greater returns than medium efficiency flocks, and 12.19–14.25 times greater returns than low efficiency flocks. Pastoralist-only flocks had 3.82–4.01 times greater returns than pastoralist-traders. Financial losses due to mortality were on average 17.81% of the starting flock value. Fecundity and abortion rates in sheep, and parturition rate in goats, had the greatest economic impact. The developed models could support decision-making toward improving the economic performance of pastoralist flocks and the evaluation of interventions and external shocks.

First Evidence of Leishmania infantum Antibodies in Sheep (Ovis aries) from Southern Germany.

In Europe, Leishmania infantum is the most prevalent Leishmania species, and this protozoan is transmitted by phlebotomine sandflies. A recent publication has shown that sheep harbor L. infantum antibodies. This raises questions about the epidemiological role of small ruminants. Therefore, sera from small ruminants located in two southern German federal states, Baden-Wuerttemberg (BW) and Bavaria (BAV), were analyzed with an ELISA to determine the presence of L. infantum antibodies. The species, sex and age (gimmer vs. ewe) were recorded, and a univariate analysis was conducted to determine possible associations. In total, seven sheep flocks (274 sheep/10 goats) from BW and seven sheep flocks (277 sheep/78 goats) from BAV were examined. In BW, four sheep from three flocks tested positive for L. infantum antibodies. In BAV, the same number of positive sheep were detected but in four flocks. The total seropositivity rate in sheep was 1.45%. All goats tested negative. No significant association (p > 0.05) was detected between Leishmania seropositivity and the variables evaluated. Our study reveals the exposure of sheep to L. infantum in a non-endemic area. Further investigation is needed to determine whether sheep can be used as sentinels to identify new phlebotomine habitats and Leishmania risk areas.

Use of coenzyme Q-10 to improve the pregnancy rate in sheep

One of the factors responsible for less pregnancy rates is the use of frozen semen in sheep due to the oxidative stress created by the process. The aim of this experiment was to test the effects of adding coenzyme Q-10 (CoQ10) to the seminal extender on sperm quality and the pregnancy rate of sheep. In this study, ejaculates from eight Dorper rams of reproductive age were used and tested in four treatments: Control (pure BotuBov®), C1 (175 µM of CoQ10), C3 (350 µM of CoQ10), and C7 (700 µM of CoQ10). Samples were collected in triplicate from each animal, and sperm analysis was performed by CASA after thawing at 0 h and 2 h. The samples were also analyzed by flow cytometry for plasma and acrosomal membrane integrity, stability, lipid peroxidation, mitochondrial potential, and superoxide anion production. In total, 198 ewes were inseminated by laparoscopy and divided into two groups: control (n=98) and C7 (n=100). Pregnancy diagnosis was performed at 30 days. Coenzyme Q10 proved to be safe for semen cryopreservation, not altering sperm kinetic values between the groups post-thawing. In flow cytometry, the C1 and C7 groups achieved a better index of plasma membrane integrity and membrane stability (P<0.05). A increased pregnancy rate was observed in C7 (52 %) compared to the control (38 %). In conclusion, coenzyme Q10 assists in the cryopreservation process, protecting the sperm cell and improving pregnancy rates in ewes.

Molecular prevalence and phylogeny of Anaplasma marginale, Anaplasma ovis and Theileria ovis in goats and sheep enrolled from a hill station in Punjab, Pakistan.

Anaplasma marginale (A. marginale), Anaplasma ovis (A. ovis) and Theileria ovis (T. ovis) are among the most commonly reported intracellular tick borne pathogens that infect ruminants across the globe causing huge economic losses. This study aims to report the prevalence and phylogenetic evaluation of these three pathogens infecting sheep and goats (n = 333) that were enrolled from Fort Munro region in Pakistan by using msp1b, msp4 and 18S rRNA genes for A. marginale, A. ovis and T. ovis respectively. Results revealed almost similar infection rates in sheep and goats with an overall prevalence of 11% for A. marginale, 28% for A. ovis and 3% for T. ovis. Concurrent infection was also recorded, however, the number of animals infected with two pathogens (n = 24; 7.2%) was higher than infection with three pathogens (n = 2; 0.6%). Risk factor analysis revealed that sheep reared in small herds had higher A. marginale (P = 0.03) and A. ovis (P = 0.04) infection rates compared to those from large herds. In addition, it was observed that bucks (P ≤ 0.05) and tick-free goats (P ≤ 0.05) exhibited higher A. ovis infection rates than nannies. Phylogenetic analysis of all three pathogens showed that Pakistani isolates were clustered together and were closely related to previously deposited Pakistani isolates as well as with those that were reported from worldwide countries. In conclusion, we are reporting that Pakistani sheep and goats have A. marginale, A. ovis and T. ovis mediated infections and control measures should be taken against them to improve the productivity of the livestock sector.

Progress on the effect of FecB mutation on BMPR1B activity and BMP/SMAD pathway in sheep.

BMPR1B is the first major gene of litter size identified in sheep. However, the molecular mechanism of the FecB mutation that increases the ovulation rate in sheep is still unclear. In recent years, it has been demonstrated that BMPR1B activity is regulated by the small molecule repressor protein FKBP1A, which acts as a key activity switch of the BMPR1B in the BMP/SMAD pathway. The FecB mutation is located close to the binding site of FKBP1A and BMPR1B. In this review, we summarize the structure of BMPR1B and FKBP1A proteins, and clarify the spatial interactive domains of the two proteins with respect to the location of the FecB mutation. Then the relationship between the FecB mutation and the degree of affinity of the two proteins are predicted. Finally, the hypothesis that FecB mutation causes change of activity in BMP/SMAD pathway by affecting the intensity of the interactions between BMPR1B and FKBP1A is proposed. This hypothesis provides a new clue to investigate the molecular mechanism of FecB mutation affecting ovulation rate and litter size in sheep.

The prevalence, virulence, and serogroups of Dichelobacter nodosus and prevalence of Fusobacterium necrophorum in footrot lesions of sheep and cattle in Morocco.

Footrot is a contagious disease of ruminants leading to severe economic losses. This study aimed to estimate the prevalence, virulence, and serogroups of Dichelobacter nodosus and the prevalence of Fusobacterium necrophorum in footrot lesions of sheep and cattle. A total of 106 pathogenic lesion samples were taken from 74 sheep and 32 cattle exhibiting typical footrot lesions and were analyzed for the presence of D. nodosus and F. necrophorum by real-time polymerase chain reaction (PCR). Both virulence and serogroup were estimated for D. nodosus positive samples. Among the 106 samples, 89 were positive by PCR for F. necrophorum, D. nodosus, or both. Dichelobacter nodosus was detected at a rate of 78.3% versus 28.3% for F. necrophorum. Virulent D. nodosus strains were detected in 67.5% of positive samples, with a higher rate in sheep (73.4%) than in cattle (47.4%). Benign D. nodosus strains were detected in 57.8% of samples, with a lower prevalence rate in sheep (50%) than in cattle (84.2%). The positive samples of D. nodosus revealed the presence of three dominant serogroups (D, H, I) and three minor serogroups (G, C, A) by serogroup-specific multiplex PCR. The findings provided information on the prevalence of D. nodosus and F. necrophorum strains in footrot lesions of sheep and cattle in some regions of Morocco, which will be useful for developing an effective autovaccine for the prevention of this disease in cattle and sheep in these regions.

Biodiversity of helminths in Karakul sheep in the Khorezm Oasis of Uzbekistan

The purpose of the research is to study the helminth fauna and the structure of helminthocenoses of Karakul sheep in the Khorezm Oasis of Uzbekistan.Materials and methods. The material for this study was helminths collected by conventional methods from Karakul sheep from farms of different types in the Khorezm Region. A total of 13 sheep were studied. To identify the dominant helminth infections in sheep, 110 sets of individual organs were examined by the method of partial helminthological dissections. Helminths were collected in slaughterhouses of the Bagat, Kushkupyr, Urgench, Yangiaryk and Shavat Districts of the Khorezm Region. Additionally, the helminths collected from sheep in the Khorezm Region for 2015–2021 were used.Results and discussion. We found that the helminth fauna of Karakul sheep from the Khorezm Oasis was represented by 22 species of the classes Cestoda, Trematoda and Nematoda. Cestodes were represented by 6 species, trematodes by 3 species, and nematodes by 13 species. The faunistic composition of helminths in studied animals was noticeably depleted as compared to other Uzbekistan regions due to natural and ecological conditions of the Khorezm Oasis. The total helminth infection rate in sheep was 100%. The intensity of infection varied depending on the season of the year and the age of sheep and ranged from tens to several thousand specimens. Almost all organs and systems of the animals were found to be ecological niches of the above helminths. Most of helminth species were common to both domesticated and wild ungulates.

A preliminary study to evaluate the effect of metformin on folliculogenesis and ovulation rate in sheep

A preliminary study to evaluate the effect of metformin on folliculogenesis and ovulation rate in sheep

EFFICACY OF BOLUSES OF RHIZOMES WITH ROOTS OF MARSH CINQUEFOIL AGAINST STRONGYLATOSES OF GASTROINTESTINAL TRACT OF SHEEP

The paper presents data on the study of the effect of boluses of rhizomes with roots of marsh cinquefoil on the body of sheep invaded by Strongylata of the gastrointestinal tract. In accordance with the data obtained, it follows that the use of boluses of rhizomes with roots of marsh cinquefoil in therapeutic doses, as an anthelminthic agent, had no negative effect on the body of animals in experimental groups, and there was a decrease in the infestation rate in sheep with strongylatoses of the gastrointestinal tract.

The effect of blood BHBA level on fertility in sheep

The aim of this study was the effect of pre-synchronization blood BHBA level on pregnancy rates of sheep in the non-breeding season. For this purpose, 100 Merino/Merino crossbred ewe, aged 2-4 years, who have given one birth before, were used in the study. For synchronization purposes, progesterone containing sponges 60 mg Medroxyprogesteron acetate (MPA) analogue, were administered intravaginally for 14 days. BHBA (betahydroxybutyric acid) measurement was made by drawing blood in each animal on the day of administration. 500-700 IU PMSG was injected at the time of sponge withdrawal. Oestrus was observed 24 hours after sponge withdrawal with the help of teaser ram. Animals which was in estrus were hand mated. Pregnancy status was recorded with the help of ultrasound using the transrectal probe in the interval 35-45 days after mating. All of the synchronized animals were determined to be in estrus and their mating were performed. As a result of the pregnancy examination, 57 (57%) of the animals became pregnant and 43 (43%) did not become pregnant. Blood BHBA values were measured in the range of 0.12 mmol/L -0.66 mmol/L (n:100) in present study and the average of BHBA as 0.35±0.083 mmol/L was determined. While blood BHBA level of pregnant animals was found as 0.29±0.005 mmol/L, blood BHBA level of non-pregnant sheep was found to be 0.41±0.073 mmol/L, which was statistically significant (p&amp;lt;0.001). In addition, it was determined that there was a strong negative correlation between blood BHBA level and pregnancy rates in sheep (r = −0.719, p&amp;lt;0.001). As a result, it was concluded that there was no study in the literature about the relationship between the fertility parameters of sheep and the blood BHBA level in the mentioned period, and it was concluded that the presented study made a significant contribution to the literature. It has been concluded that a higher fertility success can be achieved from animals with low BHBA levels, that fertility rates can be increased by regulating the energy balance of animals with high BHBA levels, and that the study can be a criterion to be considered in achieving the target of 3 lambing in 2 years in terms of herd management in sheep breeding.

Placental MRI Predicts Fetal Oxygenation and Growth Rates in Sheep and Human Pregnancy.

Magnetic resonance imaging (MRI) assessment of fetal blood oxygen saturation (SO2) can transform the clinical management of high‐risk pregnancies affected by fetal growth restriction (FGR). Here, a novel MRI method assesses the feasibility of identifying normally grown and FGR fetuses in sheep and is then applied to humans. MRI scans are performed in pregnant ewes at 110 and 140 days (term = 150d) gestation and in pregnant women at 28+3 ± 2+5 weeks to measure feto‐placental SO2. Birth weight is collected and, in sheep, fetal blood SO2 is measured with a blood gas analyzer (BGA). Fetal arterial SO2 measured by BGA predicts fetal birth weight in sheep and distinguishes between fetuses that are normally grown, small for gestational age, and FGR. MRI feto‐placental SO2 in late gestation is related to fetal blood SO2 measured by BGA and body weight. In sheep, MRI feto‐placental SO2 in mid‐gestation is related to fetal SO2 later in gestation. MRI feto‐placental SO2 distinguishes between normally grown and FGR fetuses, as well as distinguishing FGR fetuses with and without normal Doppler in humans. Thus, a multi‐compartment placental MRI model detects low placental SO2 and distinguishes between small hypoxemic fetuses and normally grown fetuses.

Evaluation of hormonal protocols for induction of synchronized estrus on reproductive indices in Kangal-Akkaraman ewes during the outbreeding season

The objective of this study was to assess the effect of human chorionic gonadotropin (hCG) and gonadotropin-releasing hormone (GnRH) treatment before sponge insertion and anti-Müllerian hormone (AMH) concentration in ewes which were either pregnant or non-pregnant during the previous breeding season. In the study, 375 (3–6-year-old) Kangal-Akkaraman ewes that conceived or did not conceive in the preceding breeding season, and 36 rams (3–6-year-old) were used. The sheep were randomly divided into 5 equal groups. Blood samples were taken before stimulation (day −4), the day stimulation was initiated (day 0), after stimulation (day 9), on the mating day (days 11–12). AMH concentrations were measured in the samples taken on − 4th day. As a conventional method, a sponge containing 20 mg of flugeston acetate (Chronogest® CR, MSD, Turkey) was placed intravaginally (day 0) into to study ewes. The ewes were intramuscularly administered 131.5 µg prostaglandin F2α (Estrumate, MSD, Turkey) and 600 IU equine chorionic gonadotropin (Chronogest® PMSG 6000, MSD, Turkey) simultaneously with sponge removal 9 days after insertion. No other treatment was applied to group 5 which served as control. Ewes in groups 1, 2, and 3 received an intramuscular injection of GnRH (4.2 µg of Buserelin acetate, Receptal, MSD, Turkey) at the time of insertion of progesterone sponge. GnRH or 600 IU hCG (Chorulon®, MSD, UK) was administered 4 days prior to sponge insertion for the ewes in the groups 2, and 3, respectively. As for the group 5 group, hCG (instead of GnRH) was administered to the ewes at the beginning of the progesterone treatment. Ewes in estrus were detected with a teaser ram and taken into a different pen with rams. Transrectal ultrasonography (Mindray DP50/Vet/US, rectal probe) was achieved during days the 30–35 following mating. Transabdominal ultrasonography was achieved during days 60–65 to detect late embryonic and early fetal death. The estrus rate was 71.19 % out of breeding season for all ewes. The pregnancy rate on day 30 post-mating was 32 % in the control group and was 31.00 %. No significant differences were observed between groups for pregnancy rates on day 30. The mean pregnancy rate in sheep that conceived and did not conceived in the preceding breeding season of the study was 32.03 % and 32.06 % respectively (P > 0.05). After treatments, AMH concentrations in non-pregnant were significantly higher than pregnant ewes (P < 0.005). In conclusion, although the AMH concentration is significantly higher in non-pregnant ewes, the AMH concentration may not be a suitable biomarker to predict induction success outside breeding season. Progesterone-based protocols may achieve an acceptable reproductive outcome in lactating ewes and the ones which experienced infertility.

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.

Study the prevalence of cysticercus tenuicollis in sheep and goats in Baghdad city

Cysticercus tenuicollis larval stage of dog’s parasite Taenia hydatigena located in visceral organs of intermediate hosts (sheep and goats). In this study, the total of 100 sheep and 100 goats’ visceral organs were inspected, C. tenuicollis was found in sheep was 21% (21/100); while the rate of infection was 35% in goats (35/100). According to the months of the study, the high rate in sheep was revealed in July, June, and August, 40% (4/10), 30% (3/10), and 25% (5/25) respectively; while the lowest rate was 10% (1/10) was recorded in January, March, April while in goats the lowest rate in March, February, and April was 20% (2/10), 30% (3/10), 30% (3/10) respectively, the rest of the months was 40% (4/10). In sheep, the highest infection rate with C. tenuicollis was 21.42% (18/84) in sheep males while the lowest rate was 18.75% (3/16) in sheep females while in goats the highest infection rate with C. tenuicollis was 35% (35/100) in males and lowest in female 0% (0).

FACTORS INFLUENCING FERTILITY IN LAPAROSCOPIC ARTIFICIAL INSEMINATION IN SHEEP.

Fertility following artificial insemination (AI) programs in sheep is affected by many variables. The aim of this study was to identify extrinsic (year, season), intrinsic (age and breed) and AI procedure related (number of AIs, synchronization protocols, semen preservation method) factors that influence fertility after laparoscopic AI in sheep. Data from 159 laparoscopic AI procedures were categorized according to year (from 2013 to 2017), season (Winter, Spring, Summer and Autumn), breed (Dorper, White Dorper, Texel, Cross-breed), age in months (≤12, 13-24, 25-36, 37-48, ≥49), estrus synchronization protocol (short-term or long-term), cumulative number of AIs (1 to 4) and semen preservation method (frozen or fresh). Frequency analysis using chi-square test was used. Year, age, number of AIs and synchronization protocols did not influence fertility after laparoscopic AI in sheep. Fertility was higher (P&lt;0.05) in sheep inseminated in spring (64.28%) and summer (54.16%) when compared to winter (36.92%) and autumn (32.14%). Dorper breed fertility (58.02%) was higher (P&lt;0.05) than White dorper (25%) and Cross-breed (30.23%). There was a lower (P&lt;0.05) pregnancy rate in sheep inseminated with frozen semen (38.27%) than sheep inseminated with fresh semen (53.84%). In conclusion, season, breed and semen preservation method can influence fertility in sheep after laparoscopic AI.

Cystic Echinococcosis in Slaughtered Cattle and Sheep from North Macedonia

Abstract Cystic echinococcosis is a cosmopolitan zoonotic infection, commonly seen in areas where livestock and dogs are kept together. The objective of this study was to investigate the prevalence of echinococcosis in slaughtered cattle and sheep in North Macedonia and to evaluate the location and fertility/sterility rates of the cysts. A total of 302 slaughtered animals were examined with visual inspection, palpation, and incision of the internal organs in order to detect cysts. Microscopic examination was carried out to determine the presence of protoscoleces. The overall prevalence of echinococcosis in slaughtered cattle and sheep was 60%. The presence of cysts increased with age in cattle. In both cattle and sheep, the most common affected organs were the liver and lungs infected with more than one cyst. The findings showed higher fertility rate in sheep which confirmed their role as the most important intermediate host. This study shows that North Macedonia is an endemic region, and serious control strategies should be implemented, with special emphasis on safety disposal of infected organs and anthelmintic treatment of the dogs.

An epidemiological study of hydatid cyst of Echinococcus granulosus isolated from sheep, goats and cattle in Sulaimani province, Kurdistan Regional-Iraq.

Cystic echinococcosis (CE) is a parasitic zoonosis caused by the larval stage of Echinococcus granulosus sensu lato with medical importance and economic effect. This study was carried out in Sulaimani province, Kurdistan Region, Iraq from October 2020 to November 2021. The study focused on the prevalence of cystic echinococcosis in slaughtered animals. The total prevalence was 8% (1324/16524), with a high rate in sheep (5.3%) and low rates in goats and cattle (1.9% and 0.76%, respectively). With respect to abattoirs involved in the study, the highest prevalence was detected in Kalar abattoir (16.8%) and the lowest in Sulaimani abattoir (4.4%). Among the infected animals, sheep in Kalar abattoir recorded the highest prevalence, while cattle in Sulaimani abattoir recorded the lowest prevalence (11.7% and 0.4%, respectively). Males of sheep, cattle, and female goats showed higher prevalence (66.7%, 76.2%, and 58.6%, respectively). Regarding organ involvements, males of cattle and sheep showed high liver involvement (81.25% and 72.2%, respectively), while females of goat showed the highest liver involvement (76%). Females of cattle and sheep showed high lung involvement (46.7% and 28.5%, respectively), but the males of goats showed the highest lung involvement (53.8%).

Local regulation of antral follicle development and ovulation in monovulatory species

The identification of mutations in the genes encoding bone morphogenetic protein 15 (BMP15) and growth and differentiation factor 9 (GDF9) associated with phenotypes of sterility or increased ovulation rate in sheep aroused interest in the study of the role of local factors in preantral and antral folliculogenesis in different species. An additive mutation in the BMP15 receptor, BMPR1b, which determines an increase in the ovulatory rate, has been introduced in several sheep breeds to increase the number of lambs born. Although these mutations indicate extremely relevant functions of these factors, the literature data on the regulation of the expression and function of these proteins and their receptors are very controversial, possibly due to differences in experimental models. The present review discusses the published data and preliminary results obtained by our group on the participation of local factors in the selection of the dominant follicle, ovulation, and follicular atresia in cattle, focusing on transforming growth factors beta and their receptors. The study of the expression pattern and the functionality of proteins produced by follicular cells and their receptors will allow increasing the knowledge about this local system, known to be involved in ovarian physiopathology and with the potential to promote contraception or increase the ovulation rate in mammals.