Egg yolk plasma enriched with ß-carotene through the diet of laying hens and adding it to the extender improves the quality of frozen semen in Arabic stallions.

Equine semen cryopreservation is one of the major procedures for the genetic conservation of rare and endangered genotypes. The current study was conducted to evaluate the effect of egg yolk plasma (EYP) enriched with ß-carotene as an antioxidant supplement on INRA-96 extender regarding freezing Arabic stallion sperm. For this purpose, ß-carotene various concentrations were utilized as a supplementary ingredient in formulating the diets of laying hens. Birds were randomly divided into four groups, fed with 0 (control), 500, 1000 and 2000 mg/kg in a supplemented diet with ß-carotene. Subsequently, various variants of enriched extender (INRA-96 + 2.5% glycerol [G]) were gained by adding 2% EYP from four treatment groups. The sperm characteristics, including motility, viability, morphology, plasma membrane integrity (HOS test), lipid peroxidation (MDA) and DNA fragmentation, were evaluated after thawing. According to the results obtained in this study, the addition of EYP from T2 and T4 (500 and 2000 mg/kg of ß-carotene in hens' diet) to the extender (INRA-96 + 2.5% G) leads to an increase in total motility (50.50% and 49.49%, respectively), progressive motility (32.6% and 31.8%, respectively), viability (68.7% and 66.1%, respectively) and plasma membrane integrity (57.7% and 50.6%, respectively). Moreover, lipid peroxidation (1.3 and 1.4 nmol/mL, respectively) and DNA fragmentation (8.6% and 9.9%, respectively) were diminished using the mentioned treatments. However, sperm morphology was not affected by the treatments. In the current study, we concluded that the optimal concentration of ß-carotene in the laying hen's diet (500 mg/kg) could reveal the best results about sperm quality. So, EYP enriched with ß-carotene acts as a valuable natural and safe supplementary material that could be exploited for enhancing stallion sperm quality in cryopreservation conditions.

Impacts of different synthetic polymers on vitrification of ovarian tissue.

Type and concentration of cryoprotective agents (CPAs) are important factors which influence the likelihood of a successful ovarian tissue vitrification outcome. In an attempt to address this factor, the present study was conducted to evaluate the impacts of different synthetic polymers (Supercool X-1000, Supercool Z-1000 and PVP K-12) on vitrification of bovine ovarian tissue. From each ovarian pair, fragments were recovered and immediately fixed for analysis (fresh control) or submitted to vitrification, either or not followed by in vitro culture for one or five days. Vitrification was performed using the ovarian tissue cryosystem (OTC) system. The ovarian tissues were intended for histological and viability analysis [Reactive oxygen species (ROS) production and degenerate cells assay (Ethidium homodimer-1)], as well as immunolocalization of AQP3 and AQP9 were measured. The results showed that during almost all the periods after warming, in treatment groups which contain polymer (X-1000, Z-1000 and PVP), the percentage of morphologically normal follicles was the highest in the X-1000 samples. Furthermore, post-thawed X-1000 group revealed stronger labeling for AQP9 in primordial and transitional follicles, when compared with others. However, morphology after cryopreservation did not correlate with follicle viability and function where the levels of degeneration and tissue damage of PVP K-12 group were lower in comparison with X-1000 group and only in PVP K-12 group, ROS level was similar to that of the fresh control group. We believe that in addition to permeating CPAs, the addition of one (Supercool X-1000) or maybe a combination (Supercool X-1000 and PVP K-12) of non-permeating polymers could be useful to improve the outcome for vitrified bovine ovarian tissue.

The impact of in ovo injection of l-arginine on hatchability, immune system and caecum microflora of broiler chickens.

The present article was conducted to evaluate the effect of in ovo injection of arginine on hatchability, immune system and caecum microflora of broiler chickens. For this reason, 300 fertile eggs were used in a completely randomized design with three experimental treatments. The experimental groups included: 1%-0.5% l-arginine (100 eggs), 2%-1% l-arginine (100 eggs), 3- control [included both sham control (injection of distilled water; 50 eggs) and control (no injection; 50 eggs)], which were injected on d 14 of incubation. After hatching, chicks of each experimental group (0.5% l-arginine, 1% l-arginine, and control groups) were randomly divided into four equal groups (as replicates) and reared for 30 days. Weight and feeding of chickens were recorded. Next, blood samples of chickens were collected on day 30 to evaluate antibody titre. Also, chickens were slaughtered on 24 and 30 days of the experiment to evaluate immune system organs and caecum microflora. Based on the results, in ovo injection of l-arginine had no significant effect on hatchability, body weight, antibody titre, spleen, bursa of Fabricius and thymus weight (p > .05). On the other hand, treatments significantly affected feed intake and feed conversion ratio (p < .05). As a novel finding, in ovo injection of l-arginine increased caecal Lactobacillus (p < .01), while decreasing Coliform and Escherichia Coli bacteria (p < .01). However, treatments did not influence caecal Enterococcus (p > .05). The overall results indicated that in ovo injection of 0.5% l-arginine had a better improving effect on caecal microflora and then considered as a recommended level of the present experiment.

Current status and future prospective of vaccine development against Echinococcus granulosus.

Cystic echinococcosis (CE) is one of the most important zoonotic parasite diseases in human, livestock, and wildlife worldwide. Development of effective vaccines against CE appears to be the most promising strategy to control this infectious disease. Use of potential livestock and canine vaccines against the larval and adult stage of E. granulosus life cycle may be the key to the production of powerful vaccines. Some progress has been accomplished in the development of vaccines against hydatidosis using empirical approaches, while such immunotherapies often fail to induce adequate immune responses. Therefore, it is of great interest to identify antigens (Ags) with high immunogenicity and develop effective vaccines and adjuvant constructs against CE. To this end, various tools can be applied, including immune-based genomics and proteomics, immunoinformatics, systems vaccinology and mathematical/computational modeling. In this review, we aimed to provide comprehensive insights upon the current status of vaccination trials against E. granulosus, and also articulate some perspectives on the production of novel anti-CE vaccines. Use of novel prospective technologies is also discussed to highlight the importance of development and advancement of the next generation vaccines against E. granulosus.

How origin of ovaries influences the vitrification outcome of bovine ovarian tissue: effects of side of ovaries and corpus luteum.

Although cryopreservation of ovarian tissue has advanced greatly, it remains a challenge, and protocols should be optimized to handle the heterogeneous nature of ovarian samples. In an effort to address this factor, the present study evaluated the effects of corpus luteum (CL) and side of ovaries (right versus left) on cellular morphology and viability of vitrified bovine ovarian fragments in a closed system. The ovaries were categorized according to whether they had a CL and which side they were on, and then divided into six groups: 1) CL+ (with CL) group; 2) CL- (without CL) group; 3) right ovaries group; 4) left ovaries group; 5) fresh control group (ovaries without vitrification or culture that were not selected for CL or ovarian side) and 6) In vitro culture medium control group (non-vitrified ovaries that were not selected for the presence or absence of CL or side of the ovaries). The current study shows that the CL- and right groups had the greatest percentage of follicles with normal morphology compared to other vitrified-warmed groups. Furthermore, the levels of necrosis and tissue damage of the right cultured group were the lowest compared to other groups. It was shown that bovine ovarian tissues derived from right ovaries and ovaries without a corpus luteum can be functionally and morphologically preserved after vitrification. For the first time, the present study suggests that bovine ovarian tissue vitrification can be improved by considering the origin of the ovaries.

L-carnitine improves quality parameters and epigenetic patterns of buck's frozen-thawed semen.

Buck sperm cryopreservation is an effective method to distribute qualified sperm for reproductive purposes, but this procedure reduces sperm quality. The current study was conducted to investigate the effect of L-carnitine (LC) on the quality and epigenetic patterns of buck's post-thawed semen. Semen samples were collected from five male goats twice a week and diluted in extenders supplemented with 0 (LC-0), 1 (LC-1), 5 (LC-5) and 10 (LC-10) mM LC. Samples were cryopreserved according to standard protocol. After thawing, motility characteristics, lipid peroxidation, membrane functionality, abnormal morphology, mitochondrial activity, acrosome integrity, epigenetic modifications, viability, apoptotic-like changes and DNA fragmentation were assessed. Samples supplemented with 5 mM LC showed greater (P ≤ 0.05) total motility, progressive motility, membrane functionality, mitochondrial activity, acrosome integrity, DNA methylation, viability, and lower (P ≤ 0.05) apoptotic-like changes. Lipid peroxidation was lower (P ≤ 0.05) in LC-5 and LC-10 compared to the control group. Addition of LC to the cryopreservation extender had no effect (P > 0.05) on velocity parameters, abnormal morphology, histone modifications, or DNA fragmentation. In conclusion, supplementing the cryopreservation extender with 5 mM LC significantly preserves the quality of buck sperm after the cryopreservation process.

Vaccination with rEGVac elicits immunoprotection against different stages of Echinococcus granulosus life cycle: A pilot study.

Vaccination against dog-sheep transmission cycle is necessary to control cystic echinococcosis (CE) infection. A multi-epitope multi-antigenic recombinant vaccine was developed-comprising the three putative vaccine antigens EG95, Eg14-3-3 and EgEnolase-was cloned and expressed. In a pilot experiment, the multi-antigen vaccine was assessed in 15 dogs and 15 sheep (five experimental groups and three animals in each group) by two subcutaneous doses 28 days apart. To evaluate the efficacy of the vaccine candidate first immunological analysis were done comprising IgG and IgE antibodies and the cytokine IL-4 in sera of the immunized dogs and sheep. Serum IgG, IgE, and IL-4, in particular in the dogs, were increased after the two rounds of vaccine candidate injection, while the total number of hydatid cysts was reduced (~85.43%). This pilot trial indicated significant immune protection efficacy against E. granulosus especially in dogs, while its efficacy in sheep was not as high as dogs. The multi-antigenic candidate vaccine is proposed as a protective vaccine modality in both dogs and sheep.

Influence of Eimeria spp. infection and dietary inclusion of arginine on intestine histological parameters, serum amino acid profile and ileal amino acids digestibility in broiler chicks.

Coccidiosis is considered to be one of the most important challenge in the poultry industry causes economic losses due to the destruction in the digestive tract of chicken. It disturbs amino acids profile and their digestibility, leading to weight lost and economic burden. Using dietary arginine may decrease the adverse effects of coccidiosis on chicken digestive tract. This study aimed to evaluate the effects of dietary inclusion of arginine on intestine histological parameters, serum amino acid concentration and ileal amino acid digestibility of broiler chicks infected with coccidiosis. A total number of 384 one-d-old broiler chicks (Ross 308) of mixed sex with initial weight of 42 ±â€¯2 g was allocated into 8 groups with 8 birds/pen from grower period. At 21 days of age, broiler chicks were infected with a mixture of Eimeria spp. Broiler chicks were divided into infected and un-infected groups and received arginine at recommended levels of 85, 100, 125 and 150 %. Intestinal morphology and lesions, serum amino acid concentration and ileal amino acid digestibility were evaluated. Broiler chicks infected with Eimeria spp. showed lower villus height and villus height: crypt depth ratio and also higher intestinal lesions (P < 0.05). Coccidia infection decreased the ileal amino acid digestibility for all studied amino acids and also reduced serum concentrations of amino acids, except lysine and isoleucine (P < 0.05). Dietary supplementation of arginine especially in higher levels significantly increased villus height and villus height:crypt depth ratio and decreased lesions (P < 0.05). Moreover, dietary supplementing of arginine increased the serum concentration of arginine (P < 0.05), but it did not have any significant effect on its digestibility (P > 0.05). In sum, coccidiosis decreases amino acid digestibility and serum amino acid concentration, but dietary inclusion of higher levels of arginine significantly improved histological parameters of broiler chicks infected with coccidiosis.

A multi-method and structure-based in silico vaccine designing against Echinococcus granulosus through investigating enolase protein.

Introduction: Hydatid disease is a ubiquitous parasitic zoonotic disease, which causes different medical, economic and serious public health problems in some parts of the world. The causal organism is a multi-stage parasite named Echinococcus granulosus whose life cycle is dependent on two types of mammalian hosts viz definitive and intermediate hosts. Methods: In this study, enolase, as a key functional enzyme in the metabolism of E. granulosus (EgEnolase), was targeted through a comprehensive in silico modeling analysis and designing a host-specific multi-epitope vaccine. Three-dimensional (3D) structure of enolase was modeled using MODELLER v9.18 software. The B-cell epitopes (BEs) were predicted based on the multi-method approach and via some authentic online predictors. ClusPro v2.0 server was used for docking-based T-helper epitope prediction. The 3D structure of the vaccine was modeled using the RaptorX server. The designed vaccine was evaluated for its immunogenicity, physicochemical properties, and allergenicity. The codon optimization of the vaccine sequence was performed based on the codon usage table of E. coli K12. Finally, the energy minimization and molecular docking were implemented for simulating the vaccine binding affinity to the TLR-2 and TLR-4 and the complex stability. Results: The designed multi-epitope vaccine was found to induce anti-EgEnolase immunity which may have the potential to prevent the survival and proliferation of E. granulosus into the definitive host. Conclusion: Based on the results, this step-by-step immunoinformatics approach could be considered as a rational platform for designing vaccines against such multi-stage parasites. Furthermore, it is proposed that this multi-epitope vaccine is served as a promising preventive anti-echinococcosis agent.

Effect of resveratrol-loaded nanostructured lipid carriers supplementation in cryopreservation medium on post-thawed sperm quality and fertility of roosters.

The objective of this study was to assess the effect of resveratrol and resveratrol-loaded nanostructured lipid carriers (NLC) supplementation of semen extender on values for fertility variables of cryopreserved rooster semen. Rooster semen was cryopreserved in modified Beltsville extender containing 0 (control group), resveratrol at 20, 40 and 60 µM and resveratrol-loaded NLC at 20, 40 and 60 µM. After thawing, motility properties, abnormal morphology, viability, membrane functionality, mitochondrial activity, apoptotic status, malondialdehyde (MDA) and antioxidant activities (glutathione peroxidase (GPx), superoxide dismutase (SOD), and total antioxidant capacity (TAC)) and fertility potential (fertility and hatchability rates) were assessed. Using 40 µM resveratrol and resveratrol-loaded NLC improved total motility. The results indicated that sperm fertility and hatching rate, viability and membrane functionality were greater in the 40 µM resveratrol and resveratrol-loaded NLC compared to control group. The percentage of apoptotic spermatozoa in 40 µM resveratrol and resveratrol-loaded NLC group was less compared with the 60 µM resveratrol, 60 resveratrol-loaded NLC and control groups. Mitochondria activity was greater in the 40 µM resveratrol and resveratrol-loaded NLC extender group compared to 20 and 60 µM resveratrol, 60 resveratrol-loaded, and control groups. Also, the 40 µM resveratrol and resveratrol-loaded NLC extender group had a greater TAC and reduced MDA. Morphology and SOD were not affected by dose of resveratrol. The results indicate supplementation of the modified Beltsville extender with 40 µM resveratrol and resveratrol-loaded NLC resulted in a greater quality of frozen-thawed rooster sperm.

Effects of new synthetic cryoprotectant agents on histological characteristics of various classes of vitrified bovine pre-antral follicles.

Previous studies have reported many discrepancies about the best type and concentration of cryoprotective agents (CPAs) and biological variability among various pre-antral follicle classes after cryopreservation of ovarian tissue. The aim of this study was to investigate the impacts of some synthetic polymers on histological characteristics of different types of pre-antral follicles after bovine ovarian tissue vitrification. From each bovine ovarian pair, fragments were recovered and immediately fixed for analysis (fresh control group) or submitted to vitrification (sucrose, X-1000, Z-1000 and polyvinylpyrrolidone groups), either followed by in vitro culture for 1 or 5 days. In this case, although, the addition of X-1000 resulted in greater percentages of normal follicles for almost all pre-antral follicle classes compared to those of other groups, there are some exceptions. These results indicate that the inclusion of polyvinylpyrrolidone in the freezing media can improve the morphology of the post-warmed transitional follicles and cultured primordial follicles on day five more than other CPAs. According to the results of this study, it can be concluded that although ovarian tissue cryopreservation is often performed to preserve the primordial follicles, by choosing the best combination of permeating and non-permeating CPAs (synthetic polymers), more advanced stages of bovine pre-antral follicles, transitional, primary and secondary follicles, may also survive the cryopreservation process.

Effect of egg yolk plasma and soybean lecithin on rooster frozen-thawed sperm quality and fertility.

This experiment was conducted to study the effects of egg yolk plasma (10%, 15% and 20%), soybean lecithin (0.5%, 1% and 1.5%) and whole egg yolk (WEY) (control) on post-thawed sperm quality, hatchability and fertility outcomes. In experiment 1, sperm motility, abnormalities, membrane integrity, viability, apoptosis status, mitochondrial activity were studied following freeze-thawing. The best quality of frozen-thawed rooster sperm was chosen to be used for the assessment of the hatchability and fertility rate in experiment 2. The significantly higher percentages of post-thawing sperm total and progressive sperm motilities, membrane integrity, viability were observed in 1% soybean lecithin and 20% egg yolk plasma in comparison with 0.5 and 1% soybean lecithin, 10% egg yolk plasma and control, except for 15% egg yolk plasma (P < 0.05). Using 20% egg yolk plasma in the extender improved mitochondrial activity. Supplementation of 1% soybean lecithin and 20% egg yolk plasma into the extender resulted in the least percentages of dead sperm (P < 0.05). Sperm abnormalities and early apoptosis did not differ in various extender supplementations. In experiment 2, higher percentages of hatchability and fertility rate were observed in semen containing 1% soybean lecithin and 20% egg yolk plasma compared with the WEY group. The results showed that supplementation of the rooster sperm extender with 1% soybean lecithin and 20% egg yolk plasma resulted in higher quality of frozen-thawed sperm.

A novel B- and helper T-cell epitopes-based prophylactic vaccine against Echinococcus granulosus.

Introduction: In this study, we targeted the worm stage of Echinococcus granulosus to design a novel multi-epitope B- and helper T-cell based vaccine construct for immunization of dogs against this multi-host parasite. Methods: The vaccine was designed based on the local Eg14-3-3 antigen (Ag). DNA samples were extracted from the protoscoleces of the infected sheep's liver, and then subjected to the polymerase chain reaction (PCR) with 14-3-3 specific forward and reverse primers. For the vaccine designing, several in silico steps were undertaken. Three-dimensional (3D) structure of the local Eg14-3-3 Ag was modeled by EasyModeller software. The protein modeling accuracy was then analyzed via various validation assays. Potential transmembrane helix, signal peptide, post-translational modifications and allergenicity of Eg14-3-3 were evaluated as the preliminary measures of B-cell epitopes (BEs ) prediction. Having used many web-servers, a well-designed process was carried out for improved prediction of BEs. High ranked linear and conformational BEs were utilized for engineering the final vaccine construct. Possible T-helper epitopes (TEs) were identified by the molecular docking between 13-mer fragments of the Eg14-3-3 Ag and two high frequent dog class II MHC alleles (i.e., DLA-DRB1*01101 and DRB1*01501). The epitopes coverage was evaluated by Shannon's variability plot. Results: The final designed construct was analyzed based on different physicochemical properties, which was then codon optimized for high-level expression in Escherichia coli k12. This minigene construct is the first dog-specific epitopic vaccine construct that is established based on TEs with high-binding affinity to canine MHC alleles. Conclusion: This in silico study is the first part of a multi-antigenic vaccine designing work that represents as a novel dog-specific vaccine against E. granulosus. Here, we present key data on the step-by-step methodologies used for designing this de novo vaccine, which is under comprehensive in vivo investigations.

A novel in silico minigene vaccine based on CD4+ T-helper and B-cell epitopes of EG95 isolates for vaccination against cystic echinococcosis.

EG95 oncospheral antigen plays a crucial role in Echinococcus granulosus pathogenicity. Considering the diversity of antigen among different EG95 isolates, it seems to be an ideal antigen for designing a universal multivalent minigene vaccine, so-called multi-epitope vaccine. This is the first in silico study to design a construct for the development of global EG95-based hydatid vaccine against E. granulosus in intermediate hosts. After antigen sequence selection, the three-dimensional structure of EG95 was modeled and multilaterally validated. The preliminary parameters for B-cell epitope prediction were implemented such as the possible transmembrane helix, signal peptide, post-translational modifications and allergenicity. The high ranked linear and conformational B-cell epitopes derived from several online web-servers (e.g., ElliPro, BepiPred v1.0, BcePred, ABCpred, SVMTrip, IEDB algorithms, SEPPA v2.0 and Discotope v2.0) were utilized for multiple sequence alignment and then for engineering the vaccine construct. T-helper based epitopes were predicted by molecular docking between the high frequent ovar class II allele (Ovar-DRB1*1202) and hexadecamer fragments of the EG95 protein. Having used the immune-informatics tools, we formulated the first EG95-based minigene vaccine based on T-helper epitope with high-binding affinity to the ovar MHC allele. This designed construct was analyzed for different physicochemical properties. It was also codon-optimized for high-level expression in Escherichia coli k12. Taken all, we propose the present in silico vaccine constructs as a promising platform for the generation of broadly protective vaccines for species and genus-specific immunization of the natural hosts of the parasite.

Isolation and Proliferation of Spermatogonial Cells from Ghezel Sheep.

BACKGROUND: Sheep industry has taken steps toward transforming itself into a more efficient and competitive field. There are many varieties of sheep breeds in the world that each of them serves a useful purpose in the economies of different civilizations. Ghezel sheep is one of the Iranian important breeds that are raised for meat, milk and wool. Field of spermatogonial cell technologies provides tools for genetic improvement of sheep herd and multiple opportunities for research. Spermatogonial cells are the only stem cells capable of transmitting genetic information to future generations. METHODS: This study was designed to extend the technique of isolation and in vitro proliferation of spermatogonial cells in Ghezel sheep. RESULTS: Isolated cells were characterized further by using specific markers for type A spermatogonia, including PLZF. Also, sertoli cells were characterized by vimentin which is a specific marker for sertoli cells. After 10 days of co-culture, viability rates of the cells was above 94.7%, but after the freezing process the viability rates were 74 percent. CONCLUSION: In this study, a standard method for isolation and in vitro proliferation of spermatogonial stem cells in Ghezel sheep was developed.

Effects of adding different levels of Glutamine to modified Beltsville extender on the survival of frozen rooster semen.

The aim of the present study was to investigate the effects of l-glutamine on the quality of frozen-thawed rooster semen. Semen samples were collected from eight mature roosters (Ross 308). After initial semen assessments, samples of adequate quality were mixed together and diluted with modified Beltsville extender without l-glutamine (control) and supplemented with 2.5, 5, and 7.5mM l-glutamine. Semen straws were subjected to cryopreservation and evaluated twice at 15-day intervals. After thawing, sperm viability, total and progressive sperm motilities were measured by Eosin-Nigrosine and Computer-Aided Sperm Analysis (CASA), respectively. The results showed that sperm functions decreased on day 30 compared to day 15. The extender supplemented with 5mM glutamine improved (p<0.05) sperm viability, total and progressive sperm motilities compared to other treatments and the control group. The best level of glutamine appeared to be 2.5mM, as it provided the highest sperm membrane integrity and the lowest level of abnormalities. The results of this study suggest that the addition of glutamine to the diluent improves semen quality and using glutamine allows rooster sperm to be frozen for longer.

Effect of vitamin E and selenium nanoparticles on post-thaw variables and oxidative status of rooster semen.

This study was conducted to determine the combined effects of adding vitamin E (VitE) and selenium nanoparticle (Nano-Se) as antioxidant supplements to rooster semen extender for freezing. Semen samples were collected from 12 White Leghorn roosters and pooled. Subsequently, the samples were divided into nine equal groups using modified Beltsville extender. Extenders were supplemented with either two amounts of VitE (5 and 10µg/mL) or two amounts of Nano-Se (1% and 2%) or a combination of both VitE and Nano-Se, and no antioxidants extender (control group). Using 5µg/mL VitE and 1% of Nano-Se improved (P<0.05) total sperm motility (79.28±3.86%), progressive sperm motility (18.03±1.02%), sperm viability (81.46±2.16%) and integrity of the sperm membrane (77.21±2.12%) after the freeze-thawing process compared with control group (54.08±3.86%, 10.96±1.02%, 60.53±2.16%, and 54.47±2.12%; respectively). Also, extenders supplemented with 5µg/mL Vit E or 5µg/mL VitE and 1% Nano-Se had a lesser malondialdehyde (MDA) concentration compared to control extender (1.15±0.32, and 1.29±0.32, respectively). Total abnormal morphology of sperm was decreased (P<0.05) by adding 5 or 10µg/mL VitE alone or in combined with 1% or 2% Nano-Se. Moreover, extenders containing Nano-Se demonstrated greater glutathione peroxidase (GPx) activity compared to other extenders. Catalase (CAT) activity was greater in extender supplemented with 10µg/mL VitE and 2% Nano-Se. Moreover, higher TAC was observed in extenders supplemented with VitE and Nano-Se. It can be concluded that addition of 5µg/mL vitamin E in combined with 1% Nano-Se improved the post-thawing quality and oxidative variables of rooster semen.

In vitro developmental competence of bovine oocytes: Effect of corpus luteum and follicle size.

BACKGROUND: Previous studies reported many discrepancies about the effects of corpus luteum (CL) and ovarian follicle size on the developmental competence of oocytes. OBJECTIVE: The aim of this study was to investigate the effects of CL and different size of follicle on the developmental potential of bovine oocytes. MATERIALS AND METHODS: After ovarian classification based on presence or absence of CL, sample follicles were placed in three groups according to their diameter; small (S; 3-6 mm), medium (M; 6-9 mm), and large (L; 10-20 mm). Collected oocytes in each group were subjected to the in vitro embryo production processes. RESULTS: Results showed that, the percentages of blastocyst obtained from oocytes originating from small and medium follicles of ovaries bearing a CL (CL+S-oocytes and CL+M-oocytes, respectively) were lower (p<0.001) than those of small and medium follicles of ovaries not bearing a CL (CL-S-oocytes and CL-M-oocytes, respectively) (30.8% and 33.6% vs. 36.9% and 38.7% respectively). Although, the percentages of blastocyst obtained from CL-M-oocytes and CL-L-oocytes were greater (p< 0.001) than those of CL+S-oocytes and CL+M-oocytes. There were no significant differences in the percentages of blastocyst formation between controls (C-oocytes), CL-S-oocytes and CL+L-oocytes. CONCLUSION: According to the results of this study, the negative effect of CL on the developmental competence of bovine oocyte depends on the follicle size. Therefore, oocytes originating from large grown follicles were not influenced by negative effects of CL as much as those originating from small and medium follicles did.

Fecal egg counts for gastrointestinal nematodes are associated with a polymorphism in the MHC-DRB1 gene in the Iranian Ghezel sheep breed.

Genetic variation among sheep breeds in resistance to gastrointestinal nematodes (GIN) has been demonstrated in several production environments. Relationships between the ovine major histocompatibility complex and resistance to GIN have been studied, but few studies have systematically examined this issue in less-developed and semi-arid regions. The aim of the current study was to explore associations between fecal worm egg counts (FEC) for several GIN and polymorphisms in the DRB1 gene. One hundred male lambs were selected at 4-6 months of age from weaned animals in five flocks (n = 20 per flock). Body weights were determined, FAMACHA scores based on color of the ocular mucous membranes were assigned as an indicator of anemia, and blood and fecal samples were collected twice to evaluate FEC and blood packed cell volume (PCV) and for DNA isolation. A repeated-measures analysis of variance was used to test effects of genotype on FEC. The model included fixed effects of flock, genotype, time of measurement (1 or 2), and flock × time and genoype × time interactions, and a random (repeated) effect of lamb. Two genotypes (A1A1 and A1A2) were observed following digestion of Region 1 of Ovar-DRB1 with PstI. Genotypic frequencies were 0.73 for A1A1 and 0.27 for A1A2. FEC differed between Ovar_DRB1 genotypes A1A1 and A1A2 for Marshallagia marshalli, Strongyle, and total nematode FEC. Observed FEC were 30-41% lower for genotype A1A1. Differences among genotypes were consistent across measurement times, with no effect of genotype × measurement time interaction for any parasite class (P ≥ 0.34). A significant association was observed between FAMACHA scores and lamb PCV, and the residual correlation between these two variables was -0.51 (P < 0.001). FAMACHA scores can thus be used to detect differences among lambs in PCV, and polymorphic markers of Ovar-DRB1 have potential value as an indicator of parasite resistance in applied animal breeding programs on sheep farms in this region.

The relationship between progesterone and biochemical constituents of amniotic fluid with placenta traits in Iranian crossbred ewes (Arkhar-Merino×Ghezel).

OBJECTIVE: To determine the values of amniotic fluid (AF) progesterone and biochemical constituents and its associated placenta traits in Iranian crossbred ewes (Arkhar-Merino×Ghezel). METHODS: Sixty ewes (2-5 years old, weighing 40-50 kg) were treated with controlled internal drug release induced 30 mg progesterone for 14 d and were injected with 400 IU pregnant mare serum gonadotropin at the time of CIDR withdrawal. After the detection of estrus, ewes were hand-mated. After expelling of each fetus accompanied by fetal membranes, 10 mL AF was taken from fetal sac for spectrophotometer methods (glucose, urea, creatinine, total protein, cholesterol, triglycerides, calcium and phosphorus) and radioimmunoassay (progesterone) analysis. RESULTS: Results indicated that there were highly positive correlations between placental efficiency and cotyledon density (r=0.764, P<0.01), and negative correlation between placental weight (PW) with the total volume amniotic fluid (TVAF) (r=-0.872, P<0.01). A positive relationship was calculated between TVAF with total protein and creatinine (r=0.418, P<0.01 and r=0.639, P<0.05, respectively). However, the correlation between the glucose and PW, cotyledon length and calcium were significantly positive (r=0.704 and r=0.712; P<0.01, respectively). The findings of this study demonstrated that there were no relationships between progesterone concentrations and placental traits (P>0.01), except for PW (r=0.665). CONCLUSIONS: In conclusion, the significant correlation between the AF biochemical and progesterone with placental traits for the above-mentioned metabolites suggests that metabolic changes in AF levels will reflect the condition in the AF.