جستجوی مقالات مرتبط با کلیدواژه "خروس" در نشریات گروه "علوم دام"

Gene regulation can be assessed by allele-specific expression (ASE), which has the potential to cause phenotypic variation. The variants associated with gene regulation can be found using ASE. Transcriptomic variation in gene expression is known to play an important role in the formation of the phenotype. Single base variations resulting from transitions (C/T or G/A) or transversions (C/G, C/A, T/A, T/G) of nucleotides at the same position between individual nucleotides in genomic DNA sequences are known as single nucleotide polymorphisms (SNPs). SNPs are important molecular markers used in breeding and genetic research. Next-generation sequencing is advancing rapidly and provides a high-throughput approach for SNP discovery in the transcriptome or genome. Transcriptome studies can bridge the gaps between genotypes and phenotypes and provide insights into the mechanisms linking sequence and function. An effective transcriptome mapping and quantification technique for studying global gene expression is RNA sequencing or RNA-Seq. For this reason, RNA-Seq is a next-generation sequencing technology that can analyze gene expression profiles and the entire transcriptome. This study aimed to identify differential gene expression and SNPs in three tissues of the heart, muscle, and spleen of roosters adapted to low and high altitude regions based on open access RNA-Seq databases.

RNA-Seq data from 54 samples were collected from the SRA database in NCBI for chickens (NCBI GEO accession: GSE119387). The samples included 33.4, 30.3, and 35.3 million paired final reads of heart, muscle, and spleen tissues, each 100 bp in length. Illumina Hiseq 2000 was used to perform mRNA sequencing. The fastq-dump command in Sratoolkit 2.11 was used to convert data from SRA to FASTQ format  FastQC (version 0.11) was used to assess data quality and Trimmomatic (version 0.33) was used to trim the reads to eliminate adapters and low-quality sequences. Trimmed reads were aligned to the reference genome of the chicken species (Gallus gallus domesticus) and the gene annotation data (GRC6a) from Tophat2, whose core host is Bowtie2. By independently aligning and mapping the RNA-Seq reads of each sample to the chicken reference genome, the transcriptome was assembled. Then, the differential gene expression analysis was performed with cufflinks. The Samtools program performed SNP detection. Finally, using the R software (version 4.2.2), the chi-square test was used to compare the amount of expressed reference and alternative alleles in the polymorphic regions of heterozygous individuals to find the notable variations.

As a result of gene expression analysis, 2260 genes were significantly differential expression (P<0.0002). Gene ontology analysis showed that these genes are in pathways related to heat stress and immune responses to the cause of trying to maintain body temperature involved and this cause was the activation of immune pathways. Identification of 1,473,176, 388,224, and 1,169,394 SNPs in the heart, muscle, and spleen tissues was enabled by SNP calling and discovery in the assembled transcriptome. The chi-square test revealed that the ASE-SNPs in the heart, muscle, and spleen tissues were 48,906 (10.3%), 28,529 (7.3%), and 76,251 (6.3%) SNPs (P<0.05). These SNPs were associated with 7,919, 6,182, and 10,590 genes in the heart, muscle, and spleen tissues. In three tissues, the number of reference and alternative alleles was shifted by 4.5% in favor of the reference allele. This suggests that the superiority of the reference allele over the reference genome during mapping may be related to mapping bias. Among the twelve potential SNPs and ASE-SNP types found, four were transition types (Ts) and eight were transformation types (Tv). The transition type accounted for 74% of the most common polymorphisms in the heart and 77% in the muscle and spleen. For ASE-SNPs, transition mutations accounted for 70% of all mutations in the heart tissue and 75% in the muscle and spleen tissue. These mutations were also the most common. The Ts/Tv ratios for the heart, muscle, and spleen tissues were 2.3, 3, and 3 in the ASE-SNP and 2.9, 3.3, and 2.2 in all SNPs, respectively. This indicated a decrease in Ts/Tv for the heart and muscle tissues in the ASE-SNP compared to all SNPs.

The results of the current study support the validity of identifying SNPs in transcriptionally active regions of the genome using RNA-Seq data. Further research is needed to determine whether the expression differences between reference and alternative alleles found in heterozygous roosters raised in different environments are related to tolerance to environmental stressors such as low oxygen levels.

Oxidative stress plays a key role in sperm structure and function, semen quality and fertility. In poultry industries lipid peroxidation increases under chronic heat stress, particularly when the temperature exceeds 27 °C. In this situation, some practices are taken. One of important action is using pharmacological plant because of the lowest side effects. There is an increasing interest for applying natural antioxidants compare to synthetic because of the safety and low toxicity problems. The pharmacological plant generally used among foods. The use of natural antioxidant decreases sperm disorders and increases fertility. The rosemary has biological antioxidant mechanisms and belonging to thorny pharmacological plant, which is widely distributed in Europe and South-Eastern Asia. It has used in traditional medicine for its therapeutic properties. The Rosemarinus officinalis L. an evergreen perennial aromatic shrub belonging to the family Labiatae, commonly called rosemary. The rosemary is commonly used as a spice and flavoring agent in food processing. The rosemary contains some antioxidant phenolic that have been shown to provide a defense against oxidative stress from oxidizing agents and free radicals. The antioxidant capacity of rosemary is mainly related to the presence of components like carnosol, rosmanol, isorosmanol, epirosmanol, carnosic and rosmarinic acids. The antioxidant capacity of sperm is low, but enzymatic and non-enzymatic antioxidants in the seminal plasma protect sperm by scavenging the reactive oxygen species (ROS).

 Rooster’s reproductive performance is an indispensable component of breeder production because it plays a vital role in the maximum production of fertilized eggs. Existence feed supplement in the poultry industry, intermediary metabolites have been including in the diet to improve fertility and reproductive outcomes. Carnitine (β-hydroxy-γ-trimethylaminobutyrate), vitamin-like-amino acid, is a quaternary ammonium compound, that has multifunctional roles in reproduction. High concentrations of L-carnitine (LC) are present in epididymal lumen, where it participates in sperm energy balance and the maturation of spermatozoa. In light of previously reported breeder birds supplemented with dietary LC have shown improvements in semen traits and fertility parameters. The present study is an attempt to investigate the effects of several levels of dietary LC supplementation on semen quality parameters and gonadosomatic and hepatosomatic indexes at maturity and production peak.

For the present experiment, thirty-six Ross (12-week-old) breeder broilers were used for 22 weeks in a completely randomized design with three treatments (0, 250 and 500 mg L-carnitine in kg of diet) and twelve replications. All roosters were fed standard isocaloric (2754 kcal/kg) and isonitrogenous diet (12 % protein). The birds for 22 weeks in a completely randomized design with three treatments (0, 250 and 500 mg / kg of LC in the diet) and six replications were used. During the adaptation period (21-24 weeks of age), the roosters were trained by abdominal massage for semen collection. After the experimental period was commenced (24 weeks of age), semen samples were collected and evaluated for seminal attributes every two weeks (from week 24 to week 34). The following parameters were determined immediately after the semen collection; to measure the semen samples were collected weekly to evaluate semen volume, total motility, membrane functionality, mitochondria activity parameters. Also, to determine gonadosomatic and hepatosomatic indexes at 24 and 34 weeks of age, six birds in each treatment weighing then were slaughtered and immediately the testes and liver were removed and weighed.

The highest sperm motility (96.60%) was observed in birds fed 250 mg LC (P <0.04). By increasing the level of LC in the diet, sperm membrane functionality improved linearly (6.8% increase compared to control) (P <0.04). A linear trend (P = 0.06) was observed in mitochondrial activity with increasing levels of LC in the diet (69.31, 72.00 and 76.25). LC plays an essential role in energy metabolism by carrying over fatty acids in the mitochondria matrix for β-oxidation producing energy. Therefore, it provides a better supply of energy for spermatogenesis and normal physiology of sperm, are presumably improved by an optimum level of LC, as a result, sperm concentration and live. These data provide evidence that LC can be effectively used in diets up to 500 mg/kg of diet or 30 mg/kg of body weight /day for semen improvements of rooster’s breeder. At 24 weeks of age, the changes in gonadosomatic index (0.55, 0.68 and 0.64) were affected by different levels of LC (P <0.01). During testis development in the chicken (from 2 to 15 weeks of age), there is no significant increase in testicular weight, however, the early stage is the most important period for testicular development. The mature testis has seminiferous tubules with a multilayered epithelium representing the different stages of spermatogenesis. Sexual maturity is associated with the highest testes weight and consequently with the highest plasma concentration of reproductive hormones. Gonads of the mature male broiler breeder are organized into separate, comfortably discernible cellular correlations and functional compartments. It has been accepted that steroid hormones biosynthesis and generation of spermatozoa are two major actions that the testicles fundamentally carry out. The improvements in gonadosomatic Index of roosters observed in this study in response to dietary LC may be attributed, at least partly, due to improved utilization of dietary nitrogen, achieved through more efficient fat oxidation by LC. Testicles contain the seminiferous tubules and the interstitial space. Seminiferous tubules are the functional elements of the testis and sertoli cells are the principal structural basis of the seminiferous epithelium, inhabiting on the substratum membrane.

The addition of 250 and 500 mg of L-carnitine to the diet due to the increase in gonad index led to an improvement in sperm quality parameters at the beginning of the production period (puberty).

The low fertility rate of frozen sperm of poultry compared to other species is a serious challenge for artificial insemination in commercial flocks. This challenge may be related to some physiological characteristics of poultry sperm. On the other hand, osmotic, chemical and mechanical stresses during cooling processes are the most important reasons that cause structural, biochemical and functional changes in sperm, which results in a series of cascade phenomena that will lead to a decrease in sperm fertility. Quercetin is a bioactive compound with a plant origin, which has a polyphenolic chemical structure and has antioxidant properties. This composition, as an important flavonoid and a strong antioxidant, eliminates free radicals and reduces oxidative stress in chicken spermatogonia. The purpose of this study is to use quercetin in nano form in the diluent of rooster sperm during storage at 4 degrees.

Immediately after collecting semen from roosters, initial evaluations were done. Semen collected from all 15 roosters were mixed together and added to the dilution medium in order to eliminate individual effects. Different concentrations of quercetin (10, 15 and 20 μM) in three forms (unprotected and inside liposomal and NLC structures) added to base diluent composition. Then the diluted semen samples were gradually cooled at 4°C for 3 hours. Then, at time zero (immediately after the samples reach the temperature of 4°C), 24 and 48, the motility parameters, membrane integrity, lipid peroxidation, the percentage of abnormal sperms and the percentage of viability of the samples were evaluated.

The results indicated that the experimental treatments did not have a significant effect on the evaluated parameters at zero time. During 24 hours of storage at 4 degrees, 15 μM of quercetin loaded in NLC significantly improved the parameters of sperm total motility, progressive motility, viability and integrity of sperm membrane compared to the control group. During 48 hours of storage at 4 degrees, the treatment of 15 μM quercetin loaded in NLC caused a significant improvement in the parameters of sperm total motility, progressive motility, viability and integrity of sperm membrane compared to the control group. Also, the results showed that the experimental treatments did not have a significant effect on the abnormality percentage of rooster sperm during storage at 4 degrees in three times of 0, 24 and 48 hours. During 24 and 48 hours of storage at 4 degrees, the treatment of 15 μM quercetin loaded in NLC caused a significant decrease in sperm MDA compared to the control group.

The results of this experiment show that the treatment of 15 μM quercetin loaded in NLC improves many evaluated parameters and therefore it is recommended for use in rooster sperm diluent.

To investigate  the effect of rosemary powder on semen parameters and DNA fragmentation under heat stress, 40 native rooster aged 42 weeksand weighted of 2300 gramswere usedin a factorial experiment in randomized complete block design with two levels of temperature (normal and heat stress) and rosemary powder (0 and 7.5 gr/kg of diet) during 7 weeks. Heat stress and normal temperature was set 28±2ºC and 18-22º C,respectively.After two weeks adaptation,the semen sampleswere collected twice in a week from roosters during 5 weeks using dorso-abdominal massage method. The semen parameters including motility, viability ratio and DNA fragmentation were evaluated. The results showed that heat stress significantly reduced the progressive motility of sperm (type A) and with the addition of rosemary powder, sperm viability increased (P˂0.05). Addition of rosemary leaf powder at normal temperature decreased the DNA fragmentation ratio (P˂0.05). In roosters under heat stress,the DNA fragmentation rate of sperm increased and the damage rate decreased significantly with the feeding of rosemary powder (P˂0.01).  According to the results of this study, adding rosemary powder to the diet of native old roosters under heat stress conditions can improve some reproductive traits

The main challenge of breeding broiler chicken breeders is to increase the production of fertile eggs. About 70% of the decline in production during different stages of incubation is due to infertile eggs and fetal mortality. The fertility reduction in male broiler breeders after 50 weeks has been reported as the major reason for production loss. This reduction can be attributed to different factors, such as age, weight, and low semen quality. The composition of seminal long chain fatty acids (FA) is affected by the diet. Thus, a diet enriched with n-3 and n-6 FAs can alter the proportion of fatty acids in the sperm and semen plasma. The amount of n-6 FAs in the sperm membrane phospholipid increased as a result of the consumption of a commercial diet.
The phospholipid of the bird sperm is identified with a very high amount of C20-22n-6 (PUFA). The increased amount of n-3 FAs in poultry sperm has a positive effect on the quality of sperm and fertility, which leads to increased sperm motility in the oviduct and fertilization. Flaxseed is the richest dietary source of n-3 FAs, i.e. α-linolenic acid, and lignan. Flaxseed dietary increases the amount of n-3 FAs (PUFA) in the phospholipid membrane of the sperm body, while it decreases n-6 FAs in the membrane of the sperm head and the ratio of n-3:n-6. In addition, the sperm motility has a positive correlation with the amount of phospholipid and a negative correlation with the amount of free cholesterol. The ability to synthesize C20-22 polyunsaturated FAs is decreased in phospholipids with age. Thus, the inclusion of α-linolenic acid in the diet of male birds results in an accurate balance of n-6/n-3 and a rise in the ratio of phospholipid/cholesterol, which would lead to a potential dramatic change in the fertility. The present study was aimed to investigate the effects of dietary flaxseed on the sperm quality and fertility of broiler breeder roosters.

This research was conducted on the broiler chicken farm of Kimiaparvar Company. Three experimental diets were tested on 1920 Ross 308 roosters which were located in six halls. Therefore, there were two halls for each experimental diet. The first phase were performed on the 33-41 weeks old birds, after their peak of production and the second phase was continued from 53 until 61 weeks of age. The experimental diets were as follows: control diet, which was formulated based on corn-soybean oil (n-6 FAs-rich), a diet with 0.2% omega-3 (n-3 FAs-rich (Pepin)), and a diet that contained 2% whole grain flaxseed. Five birds from each hall (n=30 in total) were randomly labeled for weighing, blood and sperm sampling. The blood tests, such as glucose, cholesterol, triglyceride and urea were performed using the spectrophotometry technique. The evaluation of sperm parameters and the analysis of fatty acids were conducted by the CASA system and the chromatography method, respectively. The labelled birds were trained for semen collection over three weeks using the method of abdominal message. The semen was collected once a week from week 57 to week 61. The collected samples from 5 birds were pooled before the analysis. In week 61th, the testicles of the birds were weighed after slaughter. In addition, the percentage of fertile and infertile eggs was calculated during the period. The birds were weighed from 33-61 weeks. The evaluation of sperm characteristics included: straight-liner velocity (VSL, µm/s), curvilinear velocity (VCL, µm/s), VAP: average path velocity (VAP, µm/s), linearity (LIN, %), wobble (WOB, %), straightness (STR, %), beat cross frequency (BCF, HZ), lateral head displacement (ALH, micron), mean angle degree (MAD, deg), progressive motility (PM, %), none progressive motility (NPM, %), immotile (IM, %), and concentration (M/ml).

The dietary treatments had no significant effect on the blood parameters and the weight of testicles. Similarly, in a study adding 3% of fish oil in the diet of broiler breeder roosters did not change the testicular weight. The overall effect of dietary treatments in CASA data and motility parameters was non-significant. This is consistent with the previous studies, which showed that diets with different sources of fats have no effect on the sperm motility parameters. It has been reported that the flaxseed oil had no effect on the volume and concentration of semen.According to our analysis, the dietary treatments increased the number of fertile eggs. The percentage of fertile eggs in the flaxseed group was significantly higher than the pepin and the control groups. However, there was no significant difference in the number of fertile eggs between the pepin and the control treatments. The researches confirmed that reducing the ratio of n-6/n-3 in rooster sperm by adding α-linolenic acid sources leads to increased fertility. The treatment and age had significant impacts on the body weight of the birds, where the lowest body weight was from the group that received the flaxseed diet. This could be beneficial for the producers as weight gain leads to reduced fertility in broiler breeders.The biological studies on the fertility of birds have shown that the lipid composition is the main determinant of the required flexibility of the membrane for the flagellar movement and the penetration ability of the sperm, which would facilitate the acrosome activity and the fertilization.

Manipulation of the phospholipid fatty acids of the sperm membrane with the enriched n-3 fatty acids diet improves the fertility in roosters. Our weekly results indicate a significant improvement in the motion parameters and the quantity of sperms over some weeks during the study. This effect coincides with a significant increase in the number of fertile eggs in the flaxseed group. The flaxseed as an easy available and cheap source of n-3 FAs and lignans has more significant effects on the fertility compared with the fish oil, which is more expensive. Therefore, the whole flaxseed is an ideal dietary supplement for the broiler breeder roosters, especially for the old flocks.

Oxidative stress is an imbalance between the free radicals and the ability of the body to counteract or detoxify their harmful effects by antioxidants. Commercial poultry faces a wide range of environmental, technological, nutritional, and biological stresses, which are responsible for low productivity and reproductive performance in poultry. In addition, chronic oxidative stress can deplete antioxidant vitamins and trace elements, impair immune function resulting in significant economic losses to the poultry industry. Most of this stresses at the molecular level are associated with oxidative stress and damage to important biological molecules. High levels of fatty acids are found in the plasma membrane of sperm cells. Fatty acids and other lipid compounds in sperm membranes play an important role in regulating spermatogenesis, sperm maturation, acrosome reaction, capacity building, and membrane fusion. Specifically, sperm lipid peroxidation disrupts these functions and inhibits spermatogenesis. Oxidation of sperm fatty acids leads to the production of free oxygen radicals (ROS), which are normally necessary for physiological processes of sperm, but excessive production of ROS in sperm causes low membrane fluidity, DNA breakdown (directly by attacking the purine and pyrimidine bases), protein damage, and ultimately reduced sperm motility and fertility. ROS cause damage via single and double strand DNA breaks, cross links, and chromosomal rearrangements) vitamin E is one of the most important natural antioxidants and effective in preventing of the spermatozoa lipids oxidation. Consumption of high amounts of vitamin E (200 mg / kg diet) increases its concentration in blood and semen plasma and causes beneficial changes in antioxidant capacity and lipid profile of rooster semen in normal conditions. Therefore, the aim of this study was to investigate the effect of diet supplementation with vitamin E on the quality of frozen-thawed sperm in breeder rooster under dexamethasone-induced oxidative stress.

A total of 18 roosters of Ross 308 broiler breeder at 28 weeks of age were completely randomized with 3 experimental groups and 6 birds in each experimental group. Experimental groups include 1- Normal rooster fed basal diet (control) 2- Roosters treated with subcutaneous injection of dexamethasone 4 mg / kg body weight (DEX) 3- Dex + Vitamin E (200 mg / kg diet). After 2 weeks of habitation period and 3 weeks after experimental treatments, semen samples of roosters were collected twice a week from each rooster using abdominal massage method. Sperm viability was assessed by eosin-negrosin staining. For this purpose, mix 10 μl of diluted semen with 20 μl of dye containing eosin dye (1.67 g), nigrosin dye (10 g) and sodium citrate (2.9 g) in 100 ml of distilled water. The viability of sperm was examined by light microscope (Olympus, Japan) with a magnification of 400 × and sperms that were completely or partially reddish and those did not stain were considered died and live sperm respectively. Qualitative characteristics of sperm including viability, percentage of total (MOT, %), and progressive motility (PROG, %), plasma membrane integrity as well as malondialdehyde content, antioxidant capacity (TAC) and activity of glutathione peroxidase (GPx), superoxide dismutase enzymes (SOD) were evaluated. Statistical analyses were performed using SAS software version 9.1. Duncan’s test was used to compare groups.

The results showed that dexamethasone injection as a cause of oxidative stress, increases lipid peroxidation (9.11) and decreases antioxidant capacity (1.01) of sperm (P<0.05). Total motility (49.16), progressive motility (12.46), survival rate (50.84) and plasma membrane integrity (50.26) significantly decreased by DEX treatment (P<0.05). Dietary supplementation with vitamin E improves total motility (73.63), survival rate (74.12) and plasma membrane integrity (72.74), antioxidant capacity (1.50) and activity of glutathione peroxidase (73.58), superoxide dismutase (144.95) and reduction of malondialdehyde (4.61) compared to the other two groups (P<0.05). Progressive motility (26.33) was highest in the control group compared to the other two groups and Lateral Head Displacement (16.08) was higher in the dexamethasone group than the other experimental groups (P<0.05). These positive effect vitamin E on sperm quality could be due to its antioxidant properties.

It can be concluded that dexamethasone injection increases lipid peroxidation and decreases sperm quality. Addition of vitamin E to the broiler breeder rooster’s diet under oxidative stress condition improves the quality of frozen thawed sperm. Therefore, it is recommended to supplement the diet of broiler breeder roosters with vitamin E under oxidative stress conditions.

Using 36 Hubbard grandparent roosters at 45 weeks of age, the present study investigated the effects of supplementing vitamin E and soybean lecithin in the roosters' diet on their semen quality. The experiment was conducted in a completely randomized design with four treatments including basal diet, basal diet supplemented with vitamin E (300 mg/kg), basal diet supplemented with lecithin (1%), and basal diet supplemented with lecithin & vitamin E. Roosters were fed their diets for 60 days and semen collection was performed on days 0, 20, 40 and 60 of the experiment. The results showed that the treatment containing vitamin E + lecithin significantly improved total sperm motility and sperm concentration (P<0.05). The semen volume and sperm kinematic values were not affected by experimental diets (P>0.05). Although experimental treatments had no effect on abnormal morphology of sperm and DNA fragmentation, but membrane integrity and sperm viability were significantly increased in roosters fed diet supplemented with soybean lecithin and vitamin E (P<0.05). Malondialdehyde (MDA) concentration was also shown to be significantly lower in treatment containing vitamin E and soybean lecithin (P<0.05). The interaction effects of time× diet on total and progressive motility, sperm concentration, viability, membrane integrity and MDA content were significant (P<0.05) and these traits improved in the last days of the experiment due to diet supplemented with vitamin E+ soybean lecithin. Overall, it was concluded that supplementing aged roosters' diet with vitamin E and lecithin appears to improve sperm quality traits.

The current study aimed to optimize artificial insemination in aged broiler breeder hens in two experiments. In the first experiment, the effect of (two) different diluted semen temperatures (5 and 25 °C) of Hubbard rooster (40 roosters, 58 weeks of age) on fertility, hatchability and sperm penetration (SP) rate in the perivitelline layer of Hubbard hen (180 hens) were investigated. In the second experiment, three (different) sperm concentrations (100 (C100), 200 (C200), and 400 (C400) million sperm in 0.25 mL per hen) of Hubbard roosters (40 roosters, 62 weeks of age) on fertility, hatchability and SP rate of Hubbard broiler breeder hens (270 hens) were explored. In the first experiment, the results showed that the temperature of 5 °C of diluted semen compared to the 25 °C, increased percentage of hatchability of set eggs, hatchability of fertile eggs, and SP and decreased early embryonic mortality. The results of the second experiment showed the highest percentage of fertility and SP rate were observed at treatment C400. Also, in this experiment that highest percentage of hatchability of set eggs and hatchability of fertile eggs and lowest early embryonic mortality were observed at treatment C400. Return on investment (ROI) of the treatments C200 and C400 was approximately 2.9 and 1.4, respectively. In overall, the results of this study showed that (in attention to ROI and hatchability) to optimize artificial insemination of aged broiler breeder hens we can use a sperm concentration of 200 to 400 million in 0.25 mL per hens at 5 °C.

Serotonergic axis has an important role in reproductive process of breeder rooster flocks. The aim of this study was to evaluate semen quality parameters of Ross old broiler breeder roosters, which received serotonin inhibitor (PCPA). In this study, 16 Ross broiler breeder rooster assigned into four groups and received 0, 20, 40 and 80 ppm PAPA during 4 weeks. Then semen samples were collected and frozen. After freezing-thawing process, motion parameters, viability, membrane integrity, morphology, acrosome integrity, mitochondria activity, lipid peroxidation and DNA fragmentation were evaluated. In results, using 20 and 40 ppm PCPA improved total motility, progressive motility, membrane integrity, acrosome integrity, viability and decreased apoptosis rate in frozen-thawed semen samples. Using PCPA did not have any significant effect on morphology, mitochondria activity, lipid peroxidation and DNA fragmentation of semen samples. It seems to using 20 and 40 ppm PCPA could be a suitable method to improve Ross old broiler breeder rooster semen quality parameters after freezing-thawing process.

In order to investigate the changes of IGF-I gene transcription during the sexual maturity period of Fars native roosters, 24 roosters in the age of 5, 6, 7, and 8 months were selected randomly. In each date of sampling 6 roosters were slaughtered and testes were collected for evaluation the level of IGF-I gene transcription. The results indicated that IGF-I gene transcription in the testes of 6, 7 and 8-month roosters were increased compared to 5-month roosters while the expression of this gene did not change in 7th months compared to 6th months. The results also indicated that the level of IGF-I gene transcription did not differ significantly in left and right testes in all ages (5th-8th months) but the left and right testes weight increased in 7th and 8th months compared to 5th and 6th months. The maximum and the minimum rates of left testis length to its width were observed in 6th and 8th months respectively but this rate did not change in right testis among different ages. Histological investigation also indicated that the maximum number of Sertoli and Leydig cells in both left and right testes was observed on 8th months. In conclusion the results indicated that the gene transcription of IGF-I had an increasing procedure during the sexual maturity period of roosters (5th-8th months) and weight of the left and right testes reached to their maximum rate in 7th and 8th months.

The effect of feeding L-carnitine during pre-puberty on the quality parameters of fresh and frozen-thawed semen by using 12 Ross broiler breeder males (12 weeks) for 18 weeks, in a completely randomized design with three treatments (0, 250 and 500 mg / kg of L-carnitine in the diet) and four replications was performed. From the age of 26 to 29 weeks, semen collection was performed using abdominal massage. The sperms taken each time after dilution (with Beltsville diluent) were divided into two parts, one section was frozen and the other part was immediately examined. Motility (total and forward), viability, morphology, membrane functionality and lipid peroxidation parameters were evaluated. In fresh sperm, the correlation between L-carnitine and abnormalities was negative linear, and with viability was positive linear (P<0.05). Quadratic analysis was significant in forward Motility and MDA concentration (P<0.05). Birds that use diets containing L-carnitine, In terms of forward motility, viability, morphology and MDA concentrations in fresh sperm, And these traits, with the total motility and integrity of the plasma membrane of frozen sperm, were higher in comparison to the control group (P<0.05). Also, in the sperm after frozen-thawed, the correlation between L-carnitine and Motility (total and forward), viability and membrane integrity were positive linear (P<0.05), and the correlation between L-carnitine and MDA concentration was negative linear (P<0.05). The correlation between L-carnitine and Motility (total and forward), membrane integrity and MDA concentration were quadratic (P<0.05). According to the results, Dietary L-carnitine supplementation in pre-puberty improves the qualitative traits of sperm before and after freezing in the breeder broilers.

The purpose of this experiment was to investigate the effect of different levels of the Lavandula angustifolia extract on semen quality of broiler chickens during storage in a liquid condition at 4°C. Semen was collected from 10 Ross-308 broiler breeder roosters twice a week for 4 weeks, and immediately mixed together after the initial evaluation. The semen samples were divided into 5 parts after dilution and each received 0, 5, 10, 15 and 20 µg/ml levels of Lavandula angustifolia extract. Semen quality parameters were evaluated at 0, 3, 6, 12, 24 and 48 hours after storage at 4°C. Adding different levels of Lavandula angustifolia extract resulted significant increase in total and progressive sperm motility after 6 hours of semen storage (P<0.05). The effect of Lavandula angustifolia extract on sperm survival rate was significant (P<0.05). So that treatment with 10 μg/ml of this extract at 12, 24 and 48 hours improved this parameter compared to control (P<0.05). Adding 10 μg/ml of Lavandula angustifolia extract to seminal fluid resulted significant increase in plasma membrane integrity of the sperm after 48 hours of semen storage (P<0.05). 24 and 48 hours after semen storage in liquid condition, the least amount of sperm abnormalities belonged to treatments of 10 and 15 μg/ml extract and the highest amount was in the control and high dose extract (P<0.05). In general, the addition of Lavandula angustifolia extract at 10 μg/ml to diluted semen of broiler roosters improved sperm parameters during semen storage at 4°C.

The aim of this study was to investigate the effect of curcumin on post-thawed sperm quality parameters and fertility of male broiler breeders. Twenty 49-week-old Ross 308 broiler roosters were randomly divided into four experimental groups (n=5). Different levels of curcumin including: 0 (T1), 10 (T2), 20 (T3) and 30 (T4) mg of curcumin/bird/day were supplemented to basal diet and fed to the birds from 49-61 weeks of age. After a 5-week of feeding curcumin (49-53 weeks), sperm quality was assessed for 6 weeks (54 to 59 weeks of age) following cryopreservation of semen samples. In order to evaluate fertility rate, the semen samples from weeks 60 and 61 were thawed and artificially inseminated into 68 broiler hens (n=17). Curcumin supplementation increased total motility in the T3 and T4 groups, and progressive motility in the T2, T3, and T4 groups compared to the T1 group (P<0.05). Feeding curcumin increased the viability of sperm in T3 and T4 groups compared to the T1 group (P<0.05). Plasma membrane functionality (HOS) was increased in all curcumin-treated birds compared to the control group (P<0.05); however, the highest performance was observed in T3 and T4 groups. Curcumin supplementation increased fertility rate in T3 and T4 groups compared to the T1 group. In general, the results of this study indicated positive effects of curcumin on sperm quality and fertility of broiler breeder roosters after thawing, and the best results were obtained when 20 or 30 mg of curcumin were fed daily for 13 weeks.

The increasing use of artificial insemination (AI) in the poultry industry emphasizes the need for the sharing of good quality sperm. The evaluation of semen quality characteristics of poultry gives an excellent sign of their reproductive potential and has been reported to be a major determinant of fertility and subsequent hatchability of eggs. In poultry industry in order to take advantage of new AI techniques, proper storage of poultry semen is needed. As poultry semen is viscous, highly concentrated, with low volume, containing 6 (chicken) to 12 (turkey) billion spermatozoa/ mL, the extension of good semen with a proper diluent is required prior to AI and storage. Reproduction performance is affected some factors include; nutrition, genetic, management, and environment. One of the fundamental aim in poultry industry is production of fertile eggs with high hatchability. In reproduction physiology, male and female are important, but sire effect is more than dam because of breeding program, semen samples could be applied for females. In layer industry, number of females are more than males; so, artificial insemination is an important tool for genetic diversity and high reproductive performance. One of the major problems in artificial insemination is low quality of poultry semen. Freezing and thawing have adverse effects on sperm viability. Since lipids (poly unsaturated fatty acids) are important part of plasma membrane of sperm cells, it could be destroyed in short times of storage in a liquid condition. It has been reported that antioxidants can be employed to prevent sperm damage during chilling storage condition (Malo et al. 2011). It is well known that sperm of farm animals is highly sensitive to oxidative stress (Surai et al. 1998). The high concentration of polyunsaturated fatty acids in the cell membrane of the sperm is also considered as another key factor for susceptibility to the oxidative stress. The process of semen production of reactive oxygen species (ROS) may lead to impairment of sperm morphology, motility, and finally viability. Pharmacological plants have some antioxidant components, which decrease free radical levels in organism. One of the major problems in sperm viability is sperm fragmentation. In this case, nucleus chromatin of sperm damages or splits. In some cases, the motility and normality of the semen analysis is acceptable, but the sperm nucleus of sample is damaged.  Different tests are available for detection of sperm DNA damages like COMET assay, TUNEL assay, SCSA, and Sperm Chromatin Dispersion (SCD) test. Among these assays, the SCD test is a simple and low-cost method for the analysis of sperm DNA fragmentation (Shanmugam et al., 2014). This method is based on the principle that sperm with DNA fragmentation fails to produce halo of dispersed DNA loops when mixed with agarose followed by acid denaturation and nuclear protein removal. The halos can be visualized using bright-field microscopy after staining with Wright’s stain. This study was designed to evaluate the effects of Rosemary extract on rooster semen parameters during chilling storage condition at 4ºC.

Dimension of individual cages were 85×70×70cm. Photoperiod program was applied based on 10 h darkness and 14h light. Water and feed were ad libitum. Rooster were fed corn and soybean meals based on 2107 kcal and 12% protein per Kg of dry matter. The semen was collected twice a week for six times from 10 mature roosters using abdominal rubbing method. As the rooster responded to abdominal rubbing by everting its cloaca, the ejaculate was collected using a graduated pipette; then, total volume was recorded. Urine or fecal contamination was discarded. Fresh semen was evaluated for sperm concentration using a haemocytometer. The semen samples were diluted by Sexton extender and evaluated at 25-27 °C. Then, the samples were divided into six equal parts. Different treatments were including: 0(control), 15, 25, 35, 45 and 60 µg/ml of Rosemary extract. Rosemary extract were added to each part and kept at 4oC for 72h. The parameters included motility, viability and plasma membrane integrity were evaluated at 0, 24, 48 and 72 h after storage. Also, DNA fragmentation was evaluated 48h after storage at 4 oC. In this method, sample is affected by acid treatment and denatures sperm chromatin. For elimination of proteins from chromatin, DNA strands are scattered around the sperm head and then, a halo forms around the sperm head.  With staining, halo is visible under the microscope. Halo in fragmented sperm is very small.   Data of the experiment were analyzed by Proc ANOVA SAS software (repeated measurement) and means were compared by Duncan's multiple range test.

Sperm during time of storage undergoes different changes and potentially undergoes mechanical and oxidative damages. At the time of storage in liquid condition, free radicals are released and sperm performance decreases significantly. The results of this experiment revealed that applying 35 µg/ml Rosemary extract could decrease DNA fragmentation (P<0.05). It seems that this concentration of Rosemary extract has antioxidant properties in rooster semen. Avian sperm have high concentration of long chain polyunsaturated fatty acids within the phospholipids and therefore, are prone to peroxidation damage (Blesbois et al. 1997). Also, after 48h of storage, motility, viability and sperm plasma membrane integrity were lower in treatment 60µg/ml Rosemary extract than control group (P<0.05). Finally, it was demonstrated that 48h after storage, motility, viability and sperm plasma membrane integrity in samples treated by 35µg/ml Rosemary extract were higher than control group (P<0.05). High level of reactive oxygen species (ROS) in oxidative stress is related to DNA fragmentation. Free radicals oxidize purine and pyrimidine bases of DNA structure of sperm and it causes damage DNA structure. The prevention of free radicals is the first defense line of antioxidants against oxidative damage. Rosemarry extract improved rooster sperm quality after thawing (Shafigh et al. 2016).  This is the first study to report the use of DNA fragmentation test in rooster sperm in Iran. This is a simple technique requiring no sophisticated instruments when Wright stain is used for visualization of the halos. According to the results of this study, it seems that applying 35µg/ml Rosemary extract can be useful in rooster semen at 4 oC. Rosemary extract effectively reduced DNA fragmentation. This effect seems to be associated with the high motility of treatment (35µg/ml Rosemary extract) compare with other treatments.

Chrysin was orally administered to evaluate testicular histology and relative StAR expression of Ross 308 roosters in the current study. Twenty roosters were randomly divided into four groups and were subjected to the basal diet supplemented with different levels of Chrysin including 0 (Ch0), 25 (Ch25), 50 (Ch50) or 75 (Ch75) mg/bird/day for 12 successive weeks. At the end of trial, all birds were killed and two samples were collected from the same testicle one of which was processed for histology, whereas another was snap-frozen with liquid nitrogen to assess relative gene expression. According to the results, seminiferous tubule and epithelium diameters (p<0.05) and spermatogonial numbers (p<0.01) of both CH75 and Ch50 groups were significantly improved compared to control group. However, Leydig cell numbers and blood vessels were not significantly affected. Birds fed 75 mg of Chrysin per day had significantly higher StARtranscript level compared to other groups (p<0.05). In conclusion, oral administration of Chrysin to roosters could improve testicular histology and steroidogenic parameters in the current study.

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.

Cryopreservation of the sperm causes irreversible damage to the sperm cell. The main reason of abnormal spermatozoa during storage at low temperatures are the occurrence of lipid peroxidation (LPO), production of reactive oxygen species and antioxidants imbalances (Tuncer et al. 2010). Also, factors such as the formation of ice crystals, production of reactive oxygen species, temperature changes, lipid peroxidation, changes in membrane composition, chemical toxicity due to cryoprotectants and osmotic stress, reduce the quality of sperm after thawing (Barbas and Mascarenhas 2009). The addition of antioxidants to the diluent of bird sperm during the freezing process reduces damage to sperm and maintains motility and viability rate of sperms after its thawing, which might affect the development of artificial insemination in birds. Cysteine is a sulfur-containing amino acid with antioxidant properties that can easily penetrate the cell membrane and increases the biosynthesis of intracellular glutathione and eliminates the free oxygen radicals (Kaeoket et al. 2010, Sariozkan et al. 2009). In recent years, researchers found that the use of cysteine as an antioxidant in the freezing of various mammalian sperm (Bucak et al. 2009; Tuncer et al. 2010) improve the mobility and the viability of frozen-thawed sperm. In this study, after two weeks of adaptation period, semen was collected from eight mature roosters (Ross 308). Initial semen assessments such as volume, progressive motility, concentration, viability, and percentage of abnormal sperm were conducted in the laboratory. Next, the samples with standard quality were split into four equal aliquots and diluted (1:30; v/v) with basic extender supplemented by different concentrations of cysteine (2.5, 5 and 7.5 Mm) at 37 ˚C. In this experiment, freezing procedure was conducted in two steps. So that the 3ml of extender containing different concentrations of cysteine and semen samples, were cooled slowly at 5◦C for 2 h to reach thermal equilibrium. Then, 1 ml of the semen extender (precooled to 5◦C) was added to the semen (extender plus semen) to provide a final concentration of 100 × 106 sperm/ml and 8% glycerol at a temperature of 5℃. Immediately after 1 h the sample was loaded into 0.25 mL straws (IMV, L’Aigle, France). Then, the straws were frozen in liquid nitrogen vapor, 4 cm above the liquid nitrogen, for 7 min, and plunged into liquid nitrogen for storage. After storing, the samples were evaluated twice with an interval of 15 days and frozen straws were thawed individually at 37℃ for 30 min in a water bath and then evaluated individually. The quality of sperms in the present work was evaluated after keeping them for 15 and 30 days in liquid nitrogen. The results of this study showed that the sample diluted with 2.5 mM of cysteine indicate the highest viability performance in keeping for 15 days in the liquid nitrogen compared to the control group and samples with other dosages of this amino acid (P<0/05). The viability of the sperms diluted for 30 days is considerably lower than that of those diluted during 15 days. The integrity of the membrane of sperms diluted with 5 mM of cysteine stored in liquid nitrogen for 15 days indicate the best performance compared to the samples with other dosages of amino acid and the control group (Table 3). Based on the Table 3, the minimum abnormality of sperms was seen in the group treated with 7.5 mM of cysteine for 15 days (18.3%) while the maximum sperm abnormality was for the sperm in control group of day 30 (30.6%). Moreover, results of table 4 indicated that the samples with 2.5 mM of cysteine had the best performance in terms of total and progressive motilities among other treatments and control group
(P<0/05). It has been reported that sperm storage in the presence of cysteine improves sperm motility after freezing. In this experiment, cysteine increased the viability and motility of sperm compared to the control group, which were consistent with the results of previous studies on boar (Kaeoket et al. 2010), ram (Coyan et al. 2011), dog (Michael et al. 2010) Cow (Topraggaleh et al. 2014) and Goat (Memon et al. 2012). Moreover, the results of this study was agree with Partyka and et al. 2013 that proposed the cysteine (5 mM) improves the integrity of the rooster sperm membrane. Bucak et al. (2009) reported that the addition of cysteine (5 mM) and terhalose (50 mM) increased the amount of live and motile ram sperm after freezing-thawing process. According to the results of Ahmadian et al. (2014), the low level of cysteine in the thrice-based diluent provides the best response in the process of freezing-thawing of ram sperm, which is consistent with the results of our research.

The present study was conducted to investigate the effect of dietary Curcumin supplementation on histological parameters of testis in aged Ross 308 broiler breeder roosters. A total of twelve 48-week old broiler breeder roosters in a completely randomized design were randomly assigned to four treatments and three replicates during a 13 weeks of experimental period. Treatments included no dietary Curcumin supplementation (control group), and daily supplementation of 10, 20, and 30 mg Curcumin/birds as mixed in the basal diet. At the end of the experimental period, all of the roosters were slaughtered, and testis tissue samples were collected. Testicular weight was higher in the roosters that daily received 30 mg Curcumin compared with the control group (P<0.05). Dietary supplementation of 20 and 30 mg Curcumin/day increased the diameter of seminiferous tubule compared to the control group (P<0.05). Seminiferous epithelium thickness was dose-dependently increased in Curcumin-supplemented birds compared to the control group (P<0.05). The number of spermatogonia cells was increased in all treatment groups compared to the control group (P<0.05). The number of Leydig cells was also increased in roosters received 20 and 20 mg Curcumin/day compared to the control birds (P<0.05). However, treatments did not affect the number of testis blood vessels (P>0.05). According to the results of the present study, dietary supplementation of 30 mg Curcumin/day/bird improves testis histological parameters in aged broiler breeder roosters.

The objective of the present study was to investigate the preservative effect of green tea extract as a natural antioxidant on sperm quality parameters of rooster in the duration of an entire spermatogenesis cycle. Sixteen rooster divided into four aliquots and consumed diets supplemented with 0, 30, 60, 90 mg of green tea extract/kg of feed. On 0, 14, 28, 42, 56, 70 days after start semen fluid were collected and CASA for sperm motility, progressive motility, linearity (LIN), curvilinear velocity (VCL), amplitude of lateral head displacement (ALH), average path velocity (VAP), straight line velocity (VSL), nonapoptotic sperm and DNA fragmentation (by staining sperm with acridine orange). Treatments 3 and 4 reduced apoptotic sperm and improved some of sperm motion parameters such as ALH (P<0.05). However, in last days of experiment, treatment 4 had adverse effects on VAP and VSL (P<0.05). The least amount of green tea extract (30 mg/kg of feed) improved VAP (P<0.05). The results showed that daily consumption of 60 mg green tea extract/kg of feed, as a natural antioxidant, could possibly lead to improve some of sperm motion parameters and reduced apoptosis.