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Black seeds can affect the productive and physiological performance of birds and laboratory animals. This research aimed to study the effect of black seed levels on production and reproduction parameters in Japanese quail.

The experiment was conducted on 400 pieces of adult 12-week-old quails in 20 experimental units with four treatments and five replications for 6 weeks. Experimental treatments were control (without black seeds, feeding with a basic diet), a basic diet with 1% of black seeds, the basic diet with 2% of black seeds, and the basic diet with 3% of black seeds. At the end of the experimental period, blood was taken from one randomly selected male bird from each replicate for testosterone measurement, and they were killed to examine reproductive components. The produced quail eggs of each experimental replication were collected daily and their number was recorded and weighed separately every week. At the end of the test period, 30 quail eggs from each replication were collected for 4 days and placed in the egg combs. The selected quail eggs were arranged in the setter combs and incubated in an automatic incubator at 37.7 °C and 55% humidity. For 15 days of the setter stage, the temperature was 37.2°C and 70% humidity for 3 days of the hatcher stage. The number of chickens in each replication and their weight and losses were recorded after hatching. Reproductive parameters, including fertility rate, total hatch, and the hatch of fertile eggs, were examined at the end of the incubation period.

The reproductive components and male Japanese quail testosterone were not affected by different levels of black seed (p < 0.05). Mansour et al. (2003) showed that treated groups (olive oil, black seed oil, and pomegranate extract) slightly affected testosterone, LH, FSH, and Inhibin-B compared to the control group. Considering that black seed has many properties, it did not show an effect on testosterone levels in the treatments compared to the control treatment; however, it did not have a harmful effect on the hormone levels. Egg production was affected by experimental treatments (p < 0.05). Egg weight parameters were not affected by experimental treatments (p < 0.05). The highest percentage of egg production was recorded in the treatments with 2 and 3% of black seeds, and the lowest percentage of egg production belonged to the treatment with 1% of black seeds. Aydin et al. (2008) added black seeds to the diet of Leghorn laying hens of line strains and reported that black seeds at the levels of 2 and 3% positively affected egg production and shell quality and reduced cholesterol in the yolk. Hasankhah et al., (2021) investigated different black seed levels on the safety and performance of laying hens and reported that using 4% and 5% black seeds positively influenced egg production. Fertility and overall hatching were affected by experimental treatments (p < 0.05), but fertile eggs and the weight of hatched chicks were not affected by experimental treatments (p < 0.05). The highest and the lowest fertility and hatch belonged to the treatments with 2% and 1% of black seeds, respectively. Madrasi and Pournaji (2018) studies on the effect of black seed hydroalcoholic extract on female reproductive factors in small laboratory mice showed that this extract increased the follicle graph and corpus luteum, which could have a positive result in female fertility. Except for mid-embryonic losses, other embryonic parameters were not affected by experimental treatments (p < 0.05). Blood parameters were not affected by experimental treatments (p < 0.05). Taghiani et al. (2010) investigated the effect of black seeds (2 and 4 g/kg) in the basic diet of broiler chickens on blood parameters. Their results showed that serum biochemical parameters, including albumin, triglyceride, LDL, HDL, and total cholesterol, were not significantly affected by dietary treatments.

Based on the results of the present research, black seed can have an effect on fertility, hatchability, and egg production due to the presence of compounds such as thymoquinone, fatty acids, and piscimen, and resulting in better reproductive performance in mother quails. In general, the use of black seeds at a 2% level in the Japanese quail diet can positively affect fertility and egg production.

Ewes show estrus signs during reproduction season the in the sheep production systems and generally, the average ewes litter size is one. Therefore, due to high cost of production, sheep production is not economic. Reproduction efficiency depends on factors such as period of the breeding season, ovulation rate, conception rate, pregnancy rate, litter size and lamb viability. The interaction effect of nutrition and environment influences all of these factors. Nutrition is one of the most important factors on the ruminant’s reproduction, which has an impact effect on the overall reproductive activity during their life. Nutrients like fat show their effect on the reproduction by changing the concentrations of plasma metabolites and hormones. Hence, the objective of the present study was to investigate the effect of dietary fatty acid (FA) supplements around mating on body weight (BW) change, hormones concentration, lamb sex and birth weight and reproductive performance of Lori-Bakhtiyari ewes. One hundred and five Lori-Bakhtiyari ewes were divided into three equal groups based on age (2-4 year) and body weight (54.58 ± 1.6 kg) and randomly allocated to experimental diets (n=35). Basal diet supplemented with 10% (DM basis) calcium salt of omega-6 FA, 10% calcium salt of omega-3 FA and 10% calcium salt of saturated FA (SFA). Ewes of each group fed respective experimental diet from 30 d pre- to 30 d post-mating. Serum concentrations of hormones (insulin, estradiol and progesterone) were measured. Reproductive performance including lambing rate, twining rate, the proportion of female lambs, the proportion of male lambs, lamb birth weight and weaning weight and litter size were recorded. The results showed that feeding fat supplements did not affect on BW change of ewes. Serum concentrations of insulin, estradiol and progesterone were not influenced by the experimental diets (P > 0.05). The proportion of female lambs was higher when ewes were fed diet containing omega-6 FA compared with the other dietary groups (P < 0.05). Lambing rate, twining rate, lamb birth weight and weaning weight were not affected by different fat supplements (P > 0.05). It was concluded that feeding a diet containing calcium salts of omega-6 FA around mating, can skew the sex ratio of lambs toward females. The interaction effect of dietary FA sources with other nutrients on the sex ratio of lambs could be investigated in future research. However, further research is required to confirm these findings.

So far, changes in the vaginal microbial population during the estrous cycle have been evaluated in several livestock species such as sheep. However, changes in the rumen microbial population have not been investigated during the estrous period in sheep. In a study, the results showed that the differences in the rumen microbial population in two reproductive seasons were due to the differences caused by the reaction to day length, and nutrition did not have much effect on it. It is possible that during the reproductive and non-reproductive seasons, the animal has a different microbial population in the digestive tract. The available evidence from clinical research in animals shows that microbes in the digestive system can alter brain activity and behavior through hormonal and neural pathways. Therefore, this study mainly aims to investigate changes in the rumen microbial population during the reproductive season in the estrous period in ewes with estrus and those without estrus for any reason or are so-called anestrus. The changes in the rumen microbial population during the breeding season in the estrous period were measured for the animals showing the occurrence of estrus and those not showing this trait or were anestrous.

This research was done at the same time as the non-breeding season (late spring-beginning of July). The ewes were of Grey Shirazi breed (2-3 years old). To investigate changes in the rumen fluid microbial population in the estrus cycle in estrus and non-estrus animals, two groups of 10 animals were formed from estrus and anestrus animals with the use of teaser rams, and rumen fluid samples were collected for microbial culture and other investigations in both groups once per four days (5 times) during 17 days (like estrus cycle days). The colonies were cultured and separated using general culture media with different growth factors for anaerobic bacteria colonies, such as plate count agar, MRS agar (de Man-Rogosa - Sharpe), and starch agar. The colonies were subtracted by subtractive cultures or different diagnostic tests to identify colonies. Data were analyzed using SAS software version 1/9. Means were compared with the least square procedure and adjusted for Tukey's test.

The population difference between the two groups at 5 different times showed that the population of lactic acid bacteria (LAB) on the day of estrus showed a higher value and a significant difference with other times than the anestrus group. Lipolytic bacteria were higher on the day of estrus than on all days in both groups, with a significant difference. The comparison of different groups showed that the estrous group from times 1 to 5 in the breeding season had the highest number compared to the other groups at different times of the study (p < 0.05). Anestrous groups also had the lowest number at all times (p < 0.05). The comparison of the two estrus and anestrus groups showed that heat and ninth days had higher values than the other times. In comparing the average number of lipolytic colonies in the estrus group, the highest and the lowest numbers belonged to the 1st and the 4th times, respectively, which were significantly different from the other times (p < 0.05). The population of proteolytic bacteria had the highest number of bacteria at time 1 and showed the next values at times 2, 5, 3, and 4, respectively, compared to the estrus group at time 5 (p < 0.05). Time 5 was not significantly different from times 2 and 3 (p < 0.05). In this season, the estrus group was the highest and the lowest at times 1 and 4, respectively (p < 0.05). Times 3-5 were no different significantly (p < 0.05). In the anestrus group, times 3 and 1 had the highest number vs. the lowest numbers in times 2 and 5  (p < 0.05). Based on the comparison of the average population resulting from the counting of total bacterial colonies in the examination of different groups, the estrous group had the highest number of the average microbial population in all 5 times (p < 0.05). The lowest number belonged to two anestrus groups (p < 0.05). The population difference between the two groups at 5 different times showed that the population of LAB had a higher value only on the day of estrus, with a significant difference compared to the anestrous group. The population of lipolytic bacteria in two groups of estrus and anestrus in the 5 studied times showed that the estrus group had a higher and significant value than the anestrus group in the 4th time, i.e. the day of estrus and days 5, 6, and 17. The results showed that the total bacterial population was higher in the estrus group at all times, with a significant difference. Furthermore, anaerobic bacteria increased significantly in certain days of estrus (days 1-9) compared to the anestrous group. The population difference between the two groups at 5 different times indicated that the population of LAB had a higher value only on the day of estrus, with a significant difference compared to the anestrous group. The population of lipolytic bacteria in the two estrus and anestrus groups in the 5 studied times revealed that the estrus group had a higher and significant value than the anestrus group in 4 times, i.e. days of estrus, 5, 6, and 17. The total bacterial population in the estrous group was higher and significant at all times.

In general, the colony population of amylolytic and lipolytic bacteria and the total colonies of anaerobic bacteria are significantly different on days of the estrus cycle, which may affect reproduction. Accordingly, it is better to provide more understandable results of rumen microbial effects on estrus in ewes by increasing analyses such as hormonal changes and molecular investigations, along with microbial culture in estrus crops.

The aim of this research was to investigate the interaction effect of ruminally undegradable protein (RUP) level and flaxseed type in flushing diets of ewes on reproductive performance and ovarian activity. Seventy-two Baluchi ewes (2-3 years old) were fed one of six experimental diets. The experimental diets were: 1) diet without flaxseed with 20% RUP; 2) diet without flaxseed with 40% RUP; 3) diet containing 10% whole flaxseed with 20% RUP; 4) diet containing10% whole flaxseed with 40% RUP; 5) diet containing 10% extruded flaxseed with 20% RUP and 6) diet containing10% extruded flaxseed with 40% RUP. Dry matter intake of ewes was not affected by experimental diets. Flaxseed type significantly increased glucose, cholesterol and estrogen concentrations in 24 h before removing CIDR, and 24 hours after removing CIDR, caused a significant increase in glucose and estrogen concentration and a significant decrease in blood urea concentration of ewes (P ≤ 0.05). Increasing RUP level to 40%, significantly increased glucose and estrogen and decreased urea concentrations of ewes in 24 hours after removing CIDR (P ≤ 0.05). The diets containing of extruded flaxseed showed the highest serum progesterone concentration in 8 days after mating and finally, higher lambing rates compared to control diets. Finally, the use of flaxseed (especially in extruded form) at 10%DM with 40% RUP in flushing diets, increased the metabolites and hormones concentration associated with reproductive performance, especially glucose, cholesterol, progesterone and estrogen, and thus improves the reproductive performance of the animal.

In this study, the performance of pure and crossbreed of Lori-bakhtiyari sheep was investigated. Data related to natives were collected during 1989 to 2018 and data related to crossbreed during 2011 to 2019 were collected at Sholi station in Shahrekurd. Conception rate at lambing was 87.5% for crossbreed sheep and 86.56% for Lori-bakhtiyari sheep. Litter Size% obtained 138.22 and 114.6 for crossbreed and Lori-bakhtiyari sheep respectively. Lambing percentage obtained 120.95 and 99 for crossbreed and Lori-bakhtiyari sheep, respectively. Fecundity (produced by a ewe) for crossbreed was 1.38 and 1.15 for Lori-bakhtiyari sheep. The weaning percentage for crossbreed and Lori-bakhtiyari sheep estimated 109.49 and 90.99 respectively. Survival rate estimated 90.5% and 91.7% for crossbreed and Lori-bakhtiyari sheep, respectively. Weaning weight per kg Weight of ewes was calculated 0.593 kg for native lambs and 0.610 kg for crossbreeds, this difference was statistically significant. According to the obtained results, use of genetic production method in Lori-bakhtiyari flock led to an increase in per capita profit of each crossbreed ewes of 4286000 R compared to native ewes in 2019. This amount was calculated for crossbreed ewes after second calving 4886480 R compared to native ewes.

Zebu cattle are highly adapted to tropical regions. However, females reach puberty after taurine heifers, which affects the economic efficiency of beef cattle breeding in tropical regions. A method to identify new loci and confirm existing quantitative trait loci (QTL) is through genome-wide association studies (GWAS). QTL-assisted selection and genomic regions affecting the production and reproduction traits have been considered to increase the efficiency of selection and improve production performance. The GWAS typically focuses on genetic markers with the strongest evidence of association. However, single markers often explain only a small component of the genetic variance and hence offer a limited understanding of the trait under study. A solution to tackle the aforementioned problems, and deepen the understanding of the genetic background of complex traits, is to move up the analysis from the single nucleotide polymorphism (SNP) to the gene and gene-set levels. In a gene-set analysis, a group of related genes that harbor significant SNP previously identified in GWAS is tested for over-representation in a specific pathway. The present study aimed to conduct a GWAS based on a gene-set enrichment analysis for identifying the loci associated with age at first calving trait using the high-density SNPs.

A total of 2273 Nelore cattle (995 males and 1278 females) genotyped using the Illumina BovineHD BeadChip were used in the current study. The association analysis included females with valid first calving records as well as open heifers. The association analyses were carried out by considering deregressed estimated breeding values (dEBV) for age at first calving as response variables. Before deregression, the estimated breeding values (EBV) were obtained for the dataset by considering both the calved and non-calved heifers. Variance components and EBV were obtained using the DMU software. In the analysis of AFC, a single-trait animal model was run. The gene-set analysis consists of three different steps: the assignment of SNPs to genes, the assignment of genes to functional categories, and finally the association analysis between each functional category and the phenotype of interest. The GWAS was evaluated using the GHap package in the R program. Using the biomaRt2 R package, the SNPs were assigned to genes if they were within the genomic sequence of the gene or within a flanking region of 15 kb up- and downstream of the gene. For the assignment of the genes to functional categories, the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway databases were used. The GO database designates biological descriptors to genes based on attributes of their encoded products and it is further partitioned into three components: biological process, molecular function, and cellular component. The KEGG pathway database contains metabolic and regulatory pathways, representing the actual knowledge of molecular interactions and reaction networks. Finally, a Fisher’s exact test was performed to test for overrepresentation of the significant genes for each gene-set.

The block sizes of five SNPs were chosen to perform association studies. Gene-set enrichment analysis has proven to be a great complement to GWAS. Among available gene-set databases, GO is probably the most popular, whereas KEGG is a relatively new tool that is gaining ground in livestock genomics. We hypothesized that the use of gene set information could improve prediction. However, neither of the gene set SNP classes outperformed the standard whole-genome approach. Gene-sets have been primarily developed using data from model organisms, such as mice and flies; therefore, some of the genes included in these terms may be irrelevant for reproduction. Gene-set enrichment analysis identified candidate genes related to estrogen metabolic process (HSD17B12), synapse organization (PPFIA2 and PPFIA2), sensory perception of mechanical stimulus (MYO3A and KCNMA1), protein tyrosine kinase activity (IGF1R), the cell-cell junction (FRMD4A), GnRH signaling pathway (ADCY5), and focal adhesion (PPP1R12A). Some of the genes which were found are consistent with some previous studies and are involved in biological pathways related to fertilization, age at first calving, estrogen biosynthesis, heifer conception rate, early development of the fetus, puberty, and glucose homeostasis in the ovary.  

This study supported previous results from GWAS of reproductive traits, and also revealed additional regions in the cattle genome associated with these economically important traits. These findings could potentially be useful for genetic selection in cows.

Generally, genetic markers, associated with metabolic pathways, might be used in marker-assisted selection to improve production and reproduction traits in farm animals. Especially, some traits with low heritabilities, such as reproduction and health traits could not be easily improved by classic selection strategies. However, the use of genetic markers and marker-assisted selection are considered powerful tools for the genetic improvement of low-heritable traits. Thus, detection of genetic markers associated with production and reproduction traits is an effective way to save endangered indigenous breeds, such as the Markhoz goat, a mohair-producing breed in Iran. The thyroid hormone-responsive (THRSP) gene is a candidate gene involved in thyroid hormone functions and the lipogenesis process. This gene is a protein-coding gene, with two exons, located on chromosome 29 in goats. There are some reports on the association of THRSP with production traits in farm animals. There are limited studies on metabolic pathways of THRSP and its associations with important economic traits in small ruminants and no study on the association of THRSP and reproduction traits was found in the literature. The aim of the present study was the investigation of the THRSP gene polymorphism and its association with body weight and litter size traits in Markhoz goats.

A total of 140 blood samples of Markhoz goats were randomly collected from the Research and Breeding Station in Kurdistan province in western Iran. Genomic DNA was extracted from whole blood samples. A pair of primers were designed using the Primer 3 online software to amplify a 486 bp fragment in THRSP gene exon 1. The designed primers were as follows:Forward: 5’-AGTCTGCGGGACTCCATATG-3’ Reverse: 5’-AAAATGGGACAGGCCATGT-3’ Polymorphism of the amplified fragment was investigated using the single-strand conformational polymorphism (SSCP) method and sequencing of three random samples for each SSCP pattern. The observed sequences were aligned to the GenBank reference sequence using the MegAlign module of DNAStar software and compared based on the Clustal W method. The sequences were translated by the Translate section of the ExPASy website (us.expasy.org/translatetool). Associations of body weight traits, including birth weight, three-month, six-month, nine-month, and 12-month body weights, with the observed genotypes were investigated using a general linear model, fitting genotype, birth year, birth type, and dam age as the fixed factors. The association of the observed genotypes with litter size was investigated using a two-way Chi-squared test. The SAS 9.4 program was employed for the association analyses.

In the studied samples, two different SSCP patterns and two single-nucleotide polymorphisms (SNPs) were detected in 148 and 173 bp locations of the studied fragment, as g.148G>A (resulting in Arginine to Glutamine amino acids exchange) and g.173A>G (a synonymous mutation), both as heterozygous loci. In the studied population, the frequency of the double-homozygous genotype, GG/AA (0.743), was noticeably higher than the double-heterozygous genotype, which is GA/AG (0.257). The alleles G and A had high frequencies, both equal to 0.871 in the 148 and 173 bp loci, respectively. Both loci had a significant deviation from Hardy-Weinburg equilibrium (P<0.0001). Polymorphism of the studied fragment did not have any significant effect on body weight traits. A significant association was observed between the detected genotypes and litter size. Whereby, litter size in double-heterozygous does (1.21) was significantly higher than the double-homozygous individuals (1.04), (P = 0.015). The present study is probably the first report on the association of the THRSP gene with litter size in goats. The THRSP is a protein which involves in thyroid hormone function and therefore might affect many metabolic pathways. However, a significant association of the observed genotypes with prolificacy is probably due to the role of THRSP in lipids metabolism and the association of lipids metabolism with reproduction performance.

The THRSP exon 1 is polymorphic in Markhoz goats. The studied fragment did not have any significant associations with body weight traits, but it had a significant effect on litter size. Based on the results of this study, the THRSP gene could be considered a candidate gene for litter size, and the detected SNPs at 148 and 173 bp of the studied fragment, could be used for marker-assisted selection in Markhoz goats. However, more studies on possible associations between THRSP polymorphism and production and reproduction traits are still needed in other goat breeds.

In recent years, injection of stimulant solutions into fertilized eggs has been considered to improve reproductive and functional parameters in birds. So far, much research has been conducted to improve embryonic development in birds by manipulating egg nutrients. In one study, injection of dietary supplements into the eggs of birds improved hatching rate, reduced mortality rate, shortened breeding time duration, increased growth rate, and increased weight gain at the end of the rearing period (Johnston et al., 1997). Egg injection technology is not only a way to vaccinate birds against certain diseases, but it is also a practical way of injecting some of the nutrients needed by the developing embryo (Foye et al., 2005 and Uni et al., 2005). Shirazi thyme (Zataria multiflora) is one of the most well-known medicinal plants. Essential oils (EOs) of shirazi thyme, that is a yellow or dark reddish brown liquid with a strong smell and a spicy and long-lasting, cooling flavour, extracted from the distillation of leaves and flowering shoots of this herb (Momeni and Shahrokhi, 1992). Essential oils comprise a complex mixture of volatile and non-volatile compounds produced by aromatic plants as secondary metabolites (Bakkali et al 2008). The main constituents of thyme EOs are flavonoide, glycosids, tannins, saponins, steroids (such as cytosterol), triterpenoids (such as oleanolic acid and ursolic acid), and volatile oils rich in monoterpenes (Martínez-Vázquez et al., 1996).Using nanoemulsions can be a great choice for the use of essential oils in foods (Jo et al., 2005). Changing the particle size to nanoparticles (size less than 100 nm) increases the surface-to-volume ratio and increases the reactivity, making it possible to use smaller amounts of these materials than materials with larger particles (Hernández-Sierra et al., 2008). The very small size of the synthesized nanoparticles can be effective in enhancing its antimicrobial effect (Krishna et al., 2011).

This study was conducted to investigate the effect of in-ova injection of different levels of nanoemulsion of thyme essential on reproductive (fertility, total hatchability, hatch of fertile eggs and embryonic mortality rates) and blood parameters (estrogen, testosterone, glucose, triglyceride, cholesterol, LDL, HDL, total protein) in Japanese quail.

The experiment was done by using 600 Japanese quail eggs in a completely randomized design with 5 treatments, 4 replications and 30 eggs per replicate. Treatments were including: negative control (without injection), positive control (with water and emulsifier injection) as well as intra ova injection of nanoemulsified thyme essential oil at levels of 50, 100 and 150 ppm. The experimental solutions were injected into the air sac of the eggs before incubation.The daily collected eggs were kept in a room at a temperature of about 17-18 °C. The male to female quail ratio was 1:3 in the flock and the birds had free access to water and feed at all stages of the experiment. Lighting length was set at the production stage, 16 hours brightness and 8 hours dark. Experimental solutions were injected into the egg sac immediately before incubation. At the end of incubation, fertility or embryonic development, hatchability, embryonic mortality rates and age of embryonic mortality were determined. To investigate the percentage of embryonic mortality during the incubation period, the eggs that had not been hatched were broken and the eggs with embryonic losses were selected. To determine the stage of embryonic mortality, the incubation period was divided into three stages: 1 to 9 days old (black eye and feather absent), 10 to 17 days old (embryo with feather and yellow sac visible) and 17 to 18 days old (grown embryos without yolk visible externally) (Aygun and Sert, 2012). The hatched chicks from each treatment and replicate were weighed and then transferred to their own pan. Hatched chicks were reared for 8 weeks to evaluate blood parameters and genital characteristics. The ration used for all groups was similar throughout the trial period according to the recommendations of the National Research Association (NRC, 1994).

Results showed that not only the experimental treatments did not improve fertility, total hatchability, hatch of fertile eggs and embryonic mortality rates, but the highest concentration of thyme nanoemulsion (150 ppm) had a detrimental effect on these parameters compared with the control groups (p < 0.05). At the end of the breeding period, uterine weight and length, ovarian weight, weight and diameter of F1 to F3 follicles in female birds as well as testosterone concentration in male birds were not affected by levels of thyme essential oil (P>0.05). Sera estrogen concentration of female birds due to intra ova injection of higher dose of nanoemulsified thyme essential oil was higher compared to the positive control group (p < 0.05). Blood glucose in experimental treatments was not significantly different from untreated control group (P>0.05).Total serum triglyceride was lower in the treatment group receiving 100 ppm nanoemulsion essential oil than the control groups (p < 0.05). The highest cholesterol and LDL levels were in the water plus emulsifier group and the lowest levels of these parameters numerically were belonged to the 150 nm emulsion treatment. There was no significant difference in sera HDL and total protein levels between experimental treatments (P>0.05). Therefore, Blood parameters, except triglyceride, which were lower at 100 ppm concentration, had no significant changes compared to controls.

Injection of different concentrations of thyme essential oil nanoemulsions into the air sac of Japanese quail egg, not only did not improved reproductive parameters in, but also its high concentration (150 ppm) had a negative effect on these parameters. Changes in the morphometric characteristics of the reproductive system and blood parameters were also not significant. However, the concentration of triglyceride at 100 ppm level of thyme essential oil decreased compared to the control group. In general, in-ova injection of thyme essential oil nanoemulsion is not recommended to improve reproductive performance in Japanese quail.

Data mining explores hidden and invisible relationships and patterns in the vast amount of data without which these relationships may never be revealed. Determining the factors affecting dystocia in dairy cattle can help to find the weaknesses of the management of the dairy cattle industry and the resulting problems. Therefore, it is necessary to identify and manage the most important of the various genetic and non-genetic factors that affecting dystocia. The feature selection algorithm is one of the data mining methods that can be useful in this field. This study aimed to determine the most important factors affecting the dystocia of Holstein dairy cows using the feature selection algorithm. The total records were 413205, along with 14 features related to reproductive and production records. Data analyzed with four important methods of feature selection algorithm (Best-First, Greedy-Stepwise Genetic-search, and Ranker) and nine different models (CFS-Subset-Eval, Gain-Ratio-Attribute-Eval, etc.) to determine the most important factors. The results showed that the genetic-search method using Naive Bayes Tree classification of the feature selection was the most appropriate method for selecting the factors affecting dystocia with the lowest error rate (AMS = 0.011, ARAE = 0.001). The most important factors affecting dystocia were milk production, dam age at parturition, parity, gestational length, corrected milk based on 4% fat, calf sex, calf weight, the season of calving, type of calving, fat-to-protein percentage ratio, and open days. It is expected that by considering these factors, dystocia can be better managed in dairy cattle enterprises.

Pregnancy rate is an important trait in productivity of the dairy herds. To evaluate the effective management practices on pregnancy rate of Iranian Holstein herds, the reproductive management data of 60 herds (Tehran, Isfahan, Alborz, and Mashhad provinces) were collected using a questionnaire based on herd management on 2017. Statistical analysis was performed using the mixed model procedure (Proc MIXED) of SAS software, considering the management factors and region as fixed effects and herd nested in the region, as a random effect. The average number of time per day cows observed for heat was 5.7±0.5 and 11.2±1.3 minutes per time, and 80 % of farms used synchronization. Infertility problems were the reasons of 46% of the total culling rate. Also, cows with milk yield less than 17.2±0.9 kg were removed from the herd. The mean pregnancy rate of herds was 22±0.3%. Pregnancy rate was influenced by management factors such as productive herd size, production level, age and weight of heifers as the criteria for first insemination, number of active expert people in reproduction management criteria, milk yield for culling cows that do not get pregnant, genetic aspect of fertility of bulls, single observer for heat detections, frequency of pregnancy examination during pregnancy period and method of pregnancy examination. The results obtained in this study can provide useful information to benchmark Iran dairy farms for reproductive performance.

The present study was performed to identify the copy number variations and their impacts on the genes of dromedary camels using whole genome sequencing data of two Iranian dromedary camels (Yazdi camel and Trodi camel). Whole genome sequencing of the Yazdi and Trodi samples produced about 456 and 418.8 paired-end reads with a read length of 100 bp, respectively. After mapping of trimmed reads to reference genome (NCBI accession number: GCA_000767585.1), a read-depth based algorithm was used to identify copy number variations. Identified copy number variations of studied samples, were 831 for Yazdi and 312 for Trodi camels. Nearly 60% (606 genes for Yazdi and 288 for Trodi camel) of the identified variants overlapped with the genes, and the rest were in the none genic regions. The obtained results showed that important genes including genes involved in immune system function and programmed cell death have copy number variation. As well as, two important genes of studied samples, OOEP and WWC3, which are involved in mammalian reproductive function, had copy number variation.

The aim of this study was to investigate the effects of lamb weaning age on subsequent productive and reproductive performance of Lori-Bakhtiari ewes. 103 heads of lactating ewes with an average age of 3.5 years were allocated to one of three treatments as: 1.weaned early 2.weaned as in traditional sheep rearing or 3-weaned late. Rams were introduced at 60 days postpartum and were remained with ewes for 3 months. Ewes that became pregnant were remained in trial. Again, rams introduced to ewes at breeding season and were remained with ewes for 6 months. The proportion of ewes that exhibit estrus, interval from lambing to first estrus and to conception, lambing interval, conception rate and number of lambs' birth per ewes exposed to the rams were recorded. Gain rate of ewes was higher for treatments 1 and 2 in first month after weaning than other months (p<0.05). Percentage of estrus and conception rate after first parturition were significantly higher (p<0.05) for ewes in treatment 1 than treatments 2 and 3. After first parturition, ewes in group 1, returned to estrus and conception earlier compared to 2 and 3 groups (p<0.01). Average of 3 lambing interval was lower (p<0.01) for group 1 ewes than groups 2 and 3 . In second parturition, the number of lambs born per ewe exposed to the ram was higher (p<0.05) for group 1 ewes than 2 and 3 groups. It was concluded that ewe's performance were improved by weaning their lambs at 60 days of age.

In this study, production, population and economic parameters of 30 buffalo herds of Khuzestan province in two sale conditions during 2016-2017 were used to estimate the economic value for production, reproductive and survival traits. Economic value of the traits were estimated by one unit increase for each trait using the maximum profit trend. The average annual revenue, cost and profit per head of buffalo for milk and local cream condition were 60480817, 59270944 and 1209873 Rials, respectively, and for just milk sale condition were 59220881, 59270944, and -50062.7 Rials, respectively. In the milk and local cream sale condition, as a proper sale, the economic value of production traits including milk yield, fat percentage, fattening male calf weight and weaning weight were 16774, 178011, 16051 and -46070 Rials, respectively, the economic value of reproductive traits including conception rate, live birth rate, calving interval, buffalo heifer weight and age at first calving were 476142, 527296, 9504, -36668 and -76743 Rials, respectively, and the economic value of survival traits including survival rate of buffalo cow, survival rate of calf from birth to 4 months of age, survival rate of buffalo heifer from 4 months to parturition and longevity were 364946, 216406, 143588 and 72030 Rials, respectively, per head of buffalo in a year. According to the results, selection for increasing the average milk yield, fat percentage and fattening male calf weight would improve the economic condition of buffalo breeder. Considering the negative economic value of calving interval and the age at first calving, breeding in order to shorten them can increase the economic efficiency of the herd. Also, due to the superiority of milk and local cream sale condition compared to milk sale as well as taking into account that due to the lower milk production in buffalo raw milk selling was unprofitable, dairy products selling along with milk can be regarded to improve the economic efficiency.

The aim of this study was the molecular and bioinformatics analysis of regulatory upstream region of leptin and SIGLEC5 genes in association with production and reproduction traits in Holstein cattle. For this purpose, 300 blood samples were collected randomly and DNA was extracted. Two fragments of 251 and 406 bp from regulatory upstream regions of leptin and SIGLEC5 genes were amplified by PCR and genotyping was done by SSCP method. One sample from each banding pattern was sequenced and bioinformatics analysis were done by BioEdit and DNASIS MAX softwares. The SIGLEC5 locus was monomorphic, whereas, four banding patterns of A, B, C and D with frequencies of 0.25, 0.36, 0.22 and 0.17 were observed in leptin locus, respectively. Statistical analysis showed that leptin gene polymorphism was significantly (P<0.05) associated with milk lipid and status of parturition, so that cows with banding pattern A had the highest milk fat and cows with banding pattern D showed lowest milk fat. Also, cows with banding pattern D had the best status of parturition (easy birth) (P<0.05). The bioinformatics analysis showed 14 and nine motifs in SIGLEC5 and leptin genes, respectively. Therefore, according to the results of this study, leptin gene can be suggested to improve production and reproduction traits. In addition, complementary studies on other regions of SIGLEC5 gene to find relations between production and reproduction traits in Holstein cattle are highly recommended.

This study was aimed to determine the effect of dietary Curcumin supplementation on the plasma lipid profile and some sperm quality parameters in broiler breeder roosters. In a completely randomized design, a total of twenty-eight 51-weeks-old Ross-308 roosters were randomly assigned to 4 treatment groups (n=7) and individually caged for 9 successive weeks. Treatments were different levels of Curcumin that were added to a basal diet including: T1, control (no Curcumin supplement), T2, 0.006%; T3, 0.012%, and T4, 0.018% of the diet. To determine plasma lipid profile, blood samples were collected from five birds/treatment at the end of the trial. Also, semen samples were weekly collected from each bird during the experiment, and sperm motility and plasma membrane integrity were evaluated. The results showed that concentrations of the plasma glucose, triglyceride, total cholesterol, and LDL were decreased, and concentrations of HDL were increased in T3 and T4 groups compared to the control group (P < 0.05). There were no significant differences in plasma lipid profile and plasma concentration of glucose between T1 and the control group (P<0.05). Sperm plasma membrane integrity and motility were linearly improved in treated groups compared to the control (P<0.05). The highest decrease in plasma lipid profile and most improvements in sperm motility and plasma membrane integrity was observed in T4 groups compared with other groups. In conclusion, considering all the measured parameters, dietary supplementation of 0.018% Curcumin had the best response on modifying plasma lipid profiles and improving sperm quality characteristics compared with other treatments.

The aim of this experiment was to study the effects of long-term induced hyperthyroidism on the body weight and egg production. In addition the relationships between hyperthyroidism and some reproductive parameters were studied. A total of seventy 47-week-old Cobb 500 breeder hens were randomly allotted to two treatment groups (5 replicates of 7 hens each). Thyroxine was orally administered to the hyperthyroid group (0.3 mg/bird/day) for 100 consecutive days during which the body weight and egg production were recorded on a weekly basis. Effect of hyperthyroidism on plasma T4 levels was significant; but, the T3 level was not affected. Results indicated a significant decreasing effect of thyroid hormones on body weight. Thyroid hormones had no effect on egg production; however, the treatment × time (wk) interaction effect was significant on egg production. Ovarian and oviductal weight were not different between the control and hyperthyroid hens. Administration of thyroxine to breeder hens decreased the diameter of F1 follicles.

This experiment was carried out to investigate the Moghani ewe production performance improvement through reproductive management and nutrition methods during the non-breeding season in rangeland condition. For doing these projects, in one flock with 400 ewes, two groups were identified, that including group 1(estrus synchronization+hormone therapy+supplementary feeding) and group 2 or control group (without estrus synchronization+ hormone therapy+supplementary feeding). Supplementary feeding duration in pre mating for 4 weeks and 1.5 month in late gestation with concentrate were done. During the project, production, reproductive traits and economical evaluation was carried out in each two groups. For quantities data analysis of T-test methods and for qualitative traits were used of frequency table and Chi-square. The results showed that, parturition rate, lamping rate, twining rate, born lamb crop (BLC) and weaned lamb crop (WLC) in experimental group was more than control group (p<0.05). In terms of fecundity, there was significant statistical difference between two methods, so that 104.21 vs. 48.64 percent in experimental group compared with control group were observed (p<0.05). In conclusion, in non-breeding season, in Moghani ewe using of estrus synchronization+hormone therapy+supplementary feeding, have the highest economic interest compared to the control group.

The objective of this study was to evaluate the reproductive responses to different flushing treatments in Lori-Bakhtiari ewe-lambs and mature ewes.For this purpose, a total of 55 ewe-lambs and 245 mature ewes in a flock containing 400 ewes, were selected and randomly divided into three groups. The treatments were as: 1; no flushing (control), 2;flushing with barley and 3;flushing with barley and fat. Flushing diets were offered from 2 weeks before to 3 weeks after ram introduction. The conception and parturition rates in ewe-lambs, were significantly affected by treatments (p