Dietary restriction promote sperm remodeling in aged roosters based on transcriptome analysis.

BACKGROUND: The breeder rooster has played a pivotal role in poultry production by providing high-quality semen. Typically, fertility peaks between 30 and 40 weeks of age and then declines rapidly from 45 to 55 weeks of age. Research into improving fertility in aging roosters is essential to extend their productive life. While progress has been made, enhancing fertility in aging roosters remains a significant challenge. METHODS: To identify the genes related to promoting sperm remodeling in aged Houdan roosters, we combined changes in testis and semen quality with transcriptome sequencing (RNA-seq) to analyze the synchrony of semen quality and testis development. In this study, 350-day-old Houdan breeder roosters were selected for RNA-seq analysis in testis tissues from induced molting roosters (D group) and non-induced molting roosters (47DG group). All analyses of differentially expressed genes (DEGs) and functional enrichment were performed. Finally, we selected six DEGs to verify the accuracy of the sequencing by qPCR. RESULTS: Compared with the 47DG group, sperm motility (P < 0.05), sperm density (P < 0.01), and testis weight (P < 0.05) were significantly increased in roosters in the D group. Further RNA-seq analysis of the testis between the D group and 47DG group identified 61 DEGs, with 21 up-regulated and 40 down-regulated. Functional enrichment analysis showed that the DEGs were primarily enriched in the cytokine-cytokine receptor interaction, Wnt signaling pathway, MAPK signaling pathway, TGF-ß signaling pathway, and focal adhesion pathway. The qRT-PCR results showed that the expression trend of these genes was consistent with the sequencing results. WNT5A, FGFR3, AGTR2, TGFß2, ROMO1, and SLC26A7 may play a role in testis development and spermatogenesis. This study provides fundamental data to enhance the reproductive value of aging roosters.

Optimum Doses and Forms of Selenium Maintaining Reproductive Health via Regulating Homeostasis of Gut Microbiota and Testicular Redox, Inflammation, Cell Proliferation, and Apoptosis in Roosters.

BACKGROUND: There is a U-shaped relationship between dietary selenium (Se) ingestion and optimal sperm quality. OBJECTIVES: This study aimed to investigate the optimal dietary dose and forms of Se for sperm quality of breeder roosters and the relevant mechanisms. METHODS: In experiment 1, 18-wk-old Jingbai laying breeder roosters were fed a Se-deficient base diet (BD, 0.06 mg Se/kg), or the BD + 0.1, 0.2, 0.3, 0.4, 0.5, or 1.0 mg Se/kg for 9 wk. In experiment 2, the roosters were fed the BD or the BD + sodium selenite (SeNa), seleno-yeast (SeY), or Se-nanoparticles (SeNPs) at 0.2 mg Se/kg for 9 wk. RESULTS: In experiment 1, added dietary 0.2 and 0.3 mg Se/kg led to higher sperm motility and lower sperm mortality than the other groups at weeks 5, 7, and/or 9. Furthermore, added dietary 0.2-0.4 mg Se/kg produced better testicular histology and/or lower testicular 8-hydroxy-deoxyguanosine than the other groups. Moreover, integrated testicular transcriptomic and cecal microbiomic analysis revealed that inflammation, cell proliferation, and apoptosis-related genes and bacteria were dysregulated by Se deficiency or excess. In experiment 2, compared with SeNa, SeNPs slightly increased sperm motility throughout the experiment, whereas SeNPs slightly reduced sperm mortality compared with SeY at week 9. Both SeY and SeNPs decreased malondialdehyde in the serum than those of SeNa, and SeNPs led to higher glutathione peroxidase (GPX) and thioredoxin reductase activities and GPX1 and B-cell lymphoma 2 protein concentrations in the testis compared with SeY and SeNa. CONCLUSIONS: The optimal dietary Se dose for reproductive health of breeder roosters is 0.25-0.35 mg Se/kg, and SeNPs displayed better effects on reproductive health than SeNa and SeY in laying breeder roosters. The optimal doses and forms of Se maintain reproductive health of roosters associated with regulation intestinal microbiota homeostasis and/or testicular redox balance, inflammation, cell proliferation, and apoptosis.

Effects of gonadotropin-inhibitory hormone on testicular development and reproduction-related gene expression in roosters.

Gonadotropin-inhibitory hormone (GnIH) plays a crucial role in regulating reproduction in the hypothalamus of poultry and has been intensely investigated since its discovery. This study aimed to assess the effects of GnIH on testicular development, as well as on reproduction-related hormone release and gene expression levels in roosters. The administration of exogenous GnIH resulted in a significant reduction in testis weight, testis volume and semen quality (p < 0.05). Additionally, exogenous GnIH significantly up-regulates the expression of GnIH, and down-regulates the expression of PRL (p < 0.05). GnIH application also decreased the GnRH, vasoactive intestinal peptide (VIP) and luteinizing hormone ß subunit(LHß)gene expression levels. Meanwhile, by neutralizing the effects of endogenous GnIH through immunization, testicular development on day 150 in roosters was significantly promoted. Compared to the control condition, GnIH immunization significantly down-regulated the expression of the VIP and PRL genes (p < 0.05). In conclusion, we found that exogenous GnIH treatment inhibited testicular development, reduces PRL gene expression, and suppressed reproductive performance in roosters. Conversely, GnIH immunization down-regulated VIP and PRL genes, activates the reproductive system, and promotes the reproductive activity and testicular development of roosters.

The impact of magnetized drinking water on semen quality, fertility and hatchability rates of Fayoumi chicken.

The present study was conducted to interpret the effect of magnetic field on water pH and calcium form, and evaluate semen quality, fertility and hatchability rates of Fayoumi chickens receiving magnetized drinking water (MDW). A total of 180 Fayoumi chickens (20 roosters + 160 hens), 54 weeks of age, were divided into two groups. The first group served as control, which received regular drinking water, and the second group was treated with MDW. Semen was collected twice (at day 15 and day 30 of the experiment) to determine semen quality. Fertility and hatchability were determined in two patches of hatching eggs through 1-15 and 16-30 days of the experiment. Results showed that the roosters of MDW group had higher live sperm and sperm motility ratios than those of the control group throughout the experimental period (1-30 days). The abnormal sperm ratio and methylene blue reaction time of MDW-received roosters were significantly lower than those of control roosters. Fertility and hatchability percentages of MDW group were greater compared to those of regular drinking water. Conclusively, alterations in the physiochemical characteristics of MDW and the calcium form can play a role in improving semen quality, fertility, and hatchability percentages during the late laying phase.

A successful protocol for achieving anhydrobiosis of Gallus Gallus Domesticus spermatozoa while maintaining their fertility IN VIVO.

Lyophilization of avian semen is a new method for gene pool preservation. The goal of this study was to develop a protocol for the lyophilization of rooster semen with preserved fertility. Red Rhode Island rooster ejaculates (n = 20) were assessed by volume, motility, and concentration of spermatozoa. They were pooled and diluted 1:1 with a medium LCM-T20 containing trehalose (9.5 mM), exposed at 5 °C for 40 min and centrifuged, and then the supernatant was removed. Media LCM-T with trehalose (1.75 M) was added and exposed for 10 min. The semen was frozen in a thin layer in glass vials. Samples were lyophilized for 2 h at -150 … -50 °C. The water content of the samples after lyophilization was 6.1 ± 0.5% (CV 20%). The sample was rehydrated with a medium LCM-GA5 containing hyaluronic acid (40mg/100 mL media). The total motility of the spermatozoa was 1.0 ± 0.3%. From artificial insemination of virgin hens (n = 12) with rehydrated semen, one fertilized egg was obtained from eight laid eggs. All samples of perivitelline membranes of the obtained eggs had points of interaction with the spermatozoa (7-37 pcs/cm2), which confirmed the presence of viable rehydrated spermatozoa in the genital tract of the hen. To create a dry biobank for poultry, the first protocol for lyophilization of rooster semen was developed to ensure sperm fertility in vivo.

Untargeted LC-MS-based metabonomic analysis of the effect of photoperiod on the testes of broiler roosters.

Photoperiod is an important factor that stimulates the reproductive performance of broiler breeder roosters. However, the mechanism by which photoperiod affects the reproductive performance of broiler breeder roosters has not been fully studied. To study the effects of different photoperiods on the reproductive performance of broiler breeder roosters, 120 Arbor Acres broiler breeder roosters aged 20 weeks were randomly assigned to three groups (n = 40), and the three groups were treated with different photoperiod regimes: control (CTR; 12.5 h of light and 11.5 h of dark, 12.5 L: 11.5 D), short day (SD; 16 L: 8 D) and long day (LD; 8 L: 16 D). Serum and testes were collected after 4 weeks of feeding, and testosterone-related indices were detected. We found that testosterone synthesis in the testes of broiler roosters was boosted with prolonged of photoperiod. Subsequently, metabonomics was used to identify the differential endogenous metabolites that may affect the function of the testes in breeder roosters. We found compared with other groups, the concentrations of creatine, uridine monophosphate, phosphoribosyl pyrophosphate, dCMP, α-D-glucose and citric acid in the SD group decreased significantly (p < 0.05), and glyoxylic acid, D-ribose 5-phosphate, deoxyuridine and orotic acid in the SD group increased significantly (p < 0.05), while the CTR group and LD group showed no significant difference (p > 0.05). The concentrations of linoleic acid and α-linolenic acid in the LD group were increased significantly (p < 0.05) than those in the CTR and SD groups. Compared with the CTR group, the concentrations of histamine in the SD and LD groups were significant increased (p < 0.05). The 13 of the different metabolites could be used as candidate biomarkers for different photoperiods affecting testosterone synthesis, may be used to molecular breeding of high reproductive performance broiler roosters.

Prolonging photoperiod promotes testosterone synthesis of Leydig cells by directly targeting local melatonin system in rooster testes†.

The study investigated the effects of prolonging photoperiod on the synthesis of testosterone and melatonin in roosters, and the effect of melatonin on testosterone synthesis in rooster Leydig cells as well as its molecular mechanisms. We randomly divided one hundred and twenty 20-week-old roosters into three groups and provided 6, 12.5 and 16 h light, respectively. The results showed that prolonging photoperiod promoted testosterone synthesis, decreased melatonin production, and inhibited the expression of melatonin membrane receptors MEL1A, MEL1B, MEL1C, and aralkylamine N-acetyltransferase (AANAT) in rooster testes. Subsequently, rooster Leydig cells were isolated and treated with 0, 0.1, 1, 10, and 100 ng/mL melatonin for 36 h. The results suggested that melatonin inhibited testosterone synthesis in rooster Leydig cells, and silencing MEL1A and MEL1B relieved the inhibition of melatonin on testosterone synthesis. Additionally, melatonin reduced the intracellular cyclic adenosine monophosphate (cAMP) level and the phosphorylation level of cAMP-response element binding protein (CREB), and CREB overexpression alleviated the inhibition of melatonin on testosterone synthesis. Furthermore, pretreatment with cAMP activator forskolin or protein kinase A (PKA) activator 8-bromo-cAMP blocked the inhibition of melatonin on CREB phosphorylation and testosterone synthesis. These results indicated that prolonging photoperiod promoted testosterone synthesis associated with the decrease in melatonin production and membrane receptors and biosynthetic enzyme of melatonin in rooster testes, and melatonin inhibited testosterone synthesis of rooster Leydig cells by inhibiting the cAMP/PKA/CREB pathway via MEL1A and MEL1B. This may be evidence that prolonging photoperiod could promote testosterone synthesis through the inhibition of the local melatonin pathway in rooster testes.

Role of Mono- and Disaccharide Combination in Cryoprotective Medium for Rooster Semen to Ensure Cryoresistance of Spermatozoa.

The combination of saccharides in the composition of a cryopreservation medium may represent a promising method for the preservation of the reproductive cells of male birds. In the current study, cryoprotective media with a combined composition of mono- and di-saccharides were developed. The degree of penetration of reducing saccharide molecules (maltose-Mal20 medium) and non-reducing disaccharide molecules (trehalose-Treh20 medium) from the cryoprotective medium into the cytosol of rooster spermatozoa was studied. LCM control media without disaccharides were used as the control. The number of maltose molecules penetrating from the outside into the cytosol of the spermatozoon was 1.06 × 104, and the number of trehalose molecules was 3.98 × 104. Using a combination of maltose and fructose, the progressive motility of frozen/thawed semen and the fertility rates of eggs were significantly higher ((p < 0.05) 40.2% and 68.5%, respectively) than when using a combination of trehalose and fructose in a cryoprotective diluent (33.4% and 62.4%, respectively). A higher rate of chromatin integrity at the level of 92.4% was obtained when using Treh20 versus 74.5% Mal20 (p < 0.05). Maltose positively affected the preservation of frozen/thawed sperm in the genital tract of hens. On the seventh day from the last insemination when using Mal20, the fertilization of eggs was 42.6% and only 27.3% when using Treh20. Despite the same molecular weight, maltose and trehalose have different physicochemical and biological properties that determine their function and effectiveness as components of cryoprotective media.

Dietary L-carnitine affects the expression of genes involved in apoptosis and fatty acid metabolism in rooster testes.

Thirty-six 12-week-old breeder roosters (Ross 308) were randomly allocated into three groups to receive L-carnitine (LC): LC-0, LC-250 or LC-500 mg/kg of diet to evaluate the effects of dietary LC on the expression of apoptotic-related genes and desaturases and elongase mRNA transcript levels, in the cockerel testicles. Alteration of Bak (Bcl2 antagonist/killer), Bcl2, Cas3, Cas8, Cas9, Elovl2, Elovl4, Elovl5, Fads1, Fads2 and Scd expression at 24 and 34 weeks of age was compared by real-time quantitative PCR. The expression of Bcl2 and Elovl5 was significantly up-regulated (p < .05), while Cas8 expression (p < .05) and Bak/Bcl2 ratio were reduced (p < .02) in the cockerel testicles at 24 weeks of age. Although Bak mRNA abundance decreased by dietary LC, Bak/Bcl2 ratio was not affected by the treatments at 34 weeks of age. The expression of Cas3 was down-regulated, while Fads2 was up-regulated in the cockerel testicles by dietary LC at 34 weeks of age (p < .05). The results demonstrate the beneficial effects of LC supplementation in suppression of the Bak/Bcl2 ratio by altering Bak and Bcl2 mRNA abundance and, ultimately, prevention of apoptosis. Furthermore, LC increased the expression of Elovl5 and Fads2 genes which are involved in the metabolism of long chain fatty acids.

Maintenance valine, isoleucine, and tryptophan requirements for poultry.

Poultry maintenance requirements for valine, isoleucine, and tryptophan were measured by nitrogen balance using different unit systems. The nitrogen balance trial lasted 5 d with 48 h of fasting (with roosters receiving only water+sucrose) and the last 72 h for feeding and excreta collection. Forty grams of each diet first-limiting in valine, isoleucine, or tryptophan was fed by tube each day (3 d) to give a range of intakes from 0 to 101, 0 to 119, and 0 to 34 mg/kg BW d of valine, isoleucine, and tryptophan, respectively. A nitrogen-free diet containing energy, vitamins, and minerals, meeting the rooster requirements, was offered ad libitum during these three d. To confirm that the amino acids studied were limiting, a treatment was added with a control diet formulated by adding 0.24 g/kg of L-valine, 0.21 g/kg of L-isoleucine, and 0.10 g/kg of L-tryptophan to the diets with lower amino acid level. Excreta were collected during the last 3 d of the balance period and the nitrogen content of the excreta was analyzed. For each amino acid, a linear regression between nitrogen retention (NR) and amino acid intake was performed. The equations from linear regression were: NR=-98.6 (±10.1)+2.4 (±0.2)×Val, NR=-46.9 (±7.1)+2.3 (±0.1)×Ile, NR=-39.5 (±7.7)+7.3 (±0.4)×Trp; where Val, Ile, and Trp are the intakes of valine, isoleucine, and tryptophan in mg/kg body weight per d, respectively. The valine, isoleucine, and tryptophan required to maintain the body at zero NR were calculated to be 41, 20, and 5 mg/kg body weight per d, respectively. For the system unit mg per kg of metabolic weight, the intake of valine, isoleucine, and tryptophan was 59, 32, and 9, respectively. Considering the degree of maturity of the animal and body protein content (BPm (0.73)×u), the amounts of valine, isoleucine, and tryptophan required for maintenance were calculated to be 247, 134, and 37 mg per unit of maintenance protein (BPm (0.73)×u) per d. Maintenance requirement is more adequately expressed as body protein content.

The effect of caponization on tibia bone histomorphometric properties of crossbred roosters.

The negative effect of caponization on the structural, geometric and mechanical parameters of femur and tibia has been shown in a few studies. Nevertheless, its influence on tibia bone microarchitecture is still largely unknown. Therefore, this study aimed to assess the effect of castration on the microstructural parameters of the trabecular and compact bone of tibia bone in crossbred chickens. The experiment involved 96 roosters derived from crossing Yellowleg Partridge hens ([Formula: see text]-33) and Rhode Island Red cockerels (R-11) fattened until the 16th, 20th and 24th week of life. Animals were randomly divided into 2 groups of 48 each. Group I (control) consisted of intact roosters and group II (experimental) consisted of birds subjected to caponization at the 8th week of age. The castration surgery had no influence on some properties within compact bone such as osteon diameter On.Dm, osteon perimeter On.Pm, osteon area On.Ar, osteocyte lacunar number Ot.Lc.N, osteon bone area On.B.Ar, osteon wall thickness On.W.Th as well as thick-mature collagen content in all analyzed age groups of animals. Nevertheless, our results demonstrate that castration caused a decrease of Haversian canal area Hc.Ar, osteocyte lacunar area Ot.Lc.Ar and osteocyte lacunar porosity Ot.Lc.Po among the 16-week-old birds, decrease of Haversian canal perimeter Hc.Pm and increase of fraction of bone area On.B.Ar/On.Ar among 16- and 24-week-old individuals and also an increase of osteocyte lacunar density Ot.Lc.Dn in the osteons of the oldest roosters. Additionally, some microstructural parameters of trabecular bone show the negative effect of caponization. The youngest 16-week-old capons were characterized by thinnin the trabecular in the epiphysis part of tibia. Moreover, in the case of 24-week-old, there is an increase in the trabecular separation Tb.Sp with simultaneous decrease of trabecular number Tb.N compared to roosters, which may suggest the increase of the bone resorption among the oldest individuals. The increased bone turnover in the epiphysis part of the tibia bone also indicates changes in the collagen fibers distribution, where among 20-week-old animals there is a decrease in the content of immature thin collagen fibers with simultaneous increase in the content of mature thick collagen fibers. Furthermore, among the oldest 24-week-old individuals we can observe the increased thick-to-thin collagen ratio, which may be a sign of slowing down in bone formation.

A review of antioxidant strategies to improve reproduction in aging male broiler breeders.

As only 10% of the broiler breeder flock is roosters, their fertility is very important. The rooster sperm plasma membrane has high concentrations of polyunsaturated fatty acids that are sensitive to oxidative stress. Lipid peroxidation can change membrane structure, permeability, and fluidity, adversely affecting the acrosome reaction and fertility. Aging roosters have decreases in sexual behavior, serum androgen concentrations, sperm quantity and quality, and fertility. Low fertility in aging roosters is attributed to an imbalanced testicular oxidant-antioxidant system, with increased reactive oxygen species (ROS) damaging spermatogenic epithelium. However, antioxidant components can enhance antioxidant defenses in aging broiler breeder roosters. Protection against oxidative damage, particularly in the testes, improves reproductive hormone concentrations, testicular histology, sperm membrane function, and mitochondrial activity and thereby improves semen volume, sperm concentration, viability, motility, and sperm polyunsaturated fatty acid content, sperm-egg penetration, fertility, and reproductive performance. This review summarizes antioxidants that could improve fertility and reproductive performance and delay or prevent age-related declines in broiler breeder roosters, with benefits for poultry production.

The effect of hydroxy-selenomethionine on the productive and reproductive performance of old broiler breeders.

BACKGROUND: Selenium (Se) is a rare essential element that plays a vital role in the health and performance of animals. By interfering in the production of antioxidant enzymes such as glutathione peroxidase, thioredoxin reductase and methionine sulfoxide, Se plays a role in reducing the effects of oxidative stress and animal performance. OBJECTIVES: This study aimed to investigate the effect of hydroxy-selenomethionine (OH-SeMet) in the diet of broiler breeder and old broiler breeder roosters on productive performance, reproduction and sperm quality parameters. METHODS: For this purpose, 260 broiler breeders of the Ross 308 strain were used in a completely randomized design with four treatments and five replications (13 hens and one rooster in each replication). Experimental treatments included: (1) a basal diet without OH-SeMet (T1:control), (2) a broiler breeder diet without OH-SeMet and a rooster diet containing 0.1 mg/kg OH-SeMet (T2), (3) broiler breeder diet containing 0.1 mg/kg OH-SeMet and rooster diet without OH-SeMet (T3) and (4) broiler breeder and rooster diet contained 0.1 mg/kg OH-SeMet (T4). RESULTS: The results showed that T3 and T4 treatments improved egg production, egg weight, egg mass and feed conversion ratio (FCR) compared to the control treatment (p < 0.05). The fertility and hatchability percentages of T4 and T2 treatments increased compared to T1 and T3 treatments (p < 0.05). The rate of embryonic losses in T1 was higher than in other treatments. However, grade one chickens were higher in T4 than in other treatments (p < 0.05). Total motility and viability of sperms were significantly higher in T2 and T4 treatments than in T1 and T3 treatments. The sperm abnormality percentage and sperm MDA concentration decreased in T2 and T4 treatments. CONCLUSIONS: Therefore, using OH-SeMet may be a practical approach to help old broiler breeders' production and reproduction performance.

Supplementing ageing male laying breeders with lycopene alleviates oxidative stress in testis and improves testosterone secretion.

BACKGROUND: Reproductive performance is a crucial aspect of poultry production and is carefully controlled by endocrine, paracrine, and autocrine factors. This study aimed to investigate the effect of lycopene on testosterone synthesis in Leydig cells of laying breeder roosters, clarify the mechanism of lycopene improving Leydig cells function and promoting testosterone production, and explore the role of related signal transduction pathways in testosterone synthesis. RESULTS: A total of 96 healthy 55-week-old breeding roosters were randomly assigned to one of five dietary treatments. They were provided with a corn-soybean meal-based diet containing different levels of lycopene: 0 mg/kg (control), 50 mg/kg, 100 mg/kg, or 200 mg/kg. The experiment lasted for 6 weeks. With the increase in lycopene levels, the testosterone content in the plasma was significantly higher than in the control group. Testicular Leydig cells were isolated and cultured from fresh testicular tissue of 45-wk-old to 60-wk-old breeding roosters. Various doses of lycopene were administered to Leydig cells, and subsequently, cells were collected for the detection of cell viability and testosterone content. The optimal concentration of lycopene to be added was determined, and changes in mRNA expression and protein levels of key proteins involved in testosterone synthesis were investigated. The results showed that lycopene treatment significantly increased testosterone secretion, mRNA expression, and protein levels of steroid-producing enzymes. Cells were collected to measure the activity of antioxidant enzymes, the mRNA transcription level of apoptotic factors, and the protein expression of apoptotic factors after treatment with lycopene. The results showed that lycopene significantly increased the activities of antioxidant enzymes, and the ability to inhibit oxygen radicals, and decreased the content of malondialdehyde. Apoptosis was inhibited by regulating the expression of apoptosis-inducing and anti-apoptosis factors. After that, the MAPK signaling pathway and downstream SF-1, Nrf2 gene, and protein expression levels were detected. The results showed that lycopene treatment significantly increased the gene and protein expression of JNK, SF-1, and Nrf2, and significantly decreased the gene and protein expression of p38. CONCLUSIONS: Lycopene treatment could promote testosterone synthesis of testicular Leydig cells by activating MAPK-SF-1 (increasing steroid-producing enzyme level) and MAPK-Nrf2 pathways (resisting oxidative damage).

Serum inflammation and oxidative DNA damage amelioration in cocks-fed supplemental Vernonia amygdalina and zinc in aflatoxin B1 contaminated diets.

The objective of the study was to assess the comparative effects of Vernonia amygdalina leaf meal (VALM) and zinc (Zn) on the serum proinflammatory and anti-inflammatory cytokines as well as DNA damage of cocks-fed aflatoxin B1 (AFB1) contaminated diets. A total of 250 sexually mature Isa White cocks of 24 weeks old were randomly distributed into five groups (treatments) with each containing 50 birds, which was replicated five times with 10 birds per replicate. Cocks in group A were fed basal diet only, group B was fed basal diet contaminated with 1 mg AFB1/kg diet, group C received diet B (basal + 1 mg/kg AFB1) with 50 mg/kg Zn, group D was fed diet B with 2.5 g/kg VALM, and group E received diet B with 5.0 g/kg VALM, respectively. Feed and water were supplied ad libitum with fresh feed added to the feed troughs at 6:00 a.m. and 6:00 p.m., respectively. While serum tumor necrosis factor-alpha (TNF-α), interleukin 1 beta (IL-1ß), 8-hydroxy-2'-deoxyguanosine (8-OHdG), and nuclear factor kappa B (NF-κB) were significantly (P < 0.05) elevated among the cocks on diet B, significant (P < 0.05) reductions were recorded among cocks on diets C, D, and E. Conversely, birds in group B had significant (P < 0.05) depression in serum interleukin 4 (IL-4) and interleukin 10 (IL-10) while improvements (P < 0.05) were recorded among cocks in groups C, D, and E, respectively. Therefore, the inclusion of VALM offset the adverse physiological effects of AFB1 observed among group B birds. The effects were comparable with the results presented by the cocksfed diet containing Zn.

The In Vitro Evaluation of Rooster Semen Pellets Frozen with Dimethylacetamide.

Sperm cryopreservation is an effective technique for conserving animal genetic diversity and transmitting superior genetic backgrounds, maintained via a non-invasive sampling and collection of huge quantities of sperm. Nevertheless, cryopreservation in avian species is not commercially viable because of the rooster sperm's susceptibility to damage. This study aims to estimate the impact of dimethylacetamide (DMA) as a cryoprotectant at different levels (3%, 6%, or 9%) on the post-thawed sperm quality, motility, antioxidant-biomarkers, and the expression of anti-freeze related genes. Semen samples were collected twice a week from twelve roosters aged 40 wk, weighing 3400 ± 70 g, and belonging to the Cairo-B2 chicken strain. Fresh semen samples were rapidly appraised, pooled, diluted with two volumes of a basic extender, and divided equally into three groups. The diluted groups were chilled at -20 °C for 7 min, then gently supplemented with 3, 6, or 9% pre-cooled DMA and equilibrated at 5 °C for a further 10 min. Semen pellets were formed by pipetting drops 7 cm above liquid nitrogen (LN2), which were then kept inside cryovials in the LN2. Thawing was performed 2 months later by taking 3-4 pellets of the frozen semen into a glass tube and warming it in a water bath for 8 s at 60 °C. The results showed that 3% DMA increased the proportion of total motile sperm, progressivity, viability, and plasma membrane integrity (%) compared to the 6% and 9% DMA groups. The lipid peroxidation and antioxidant enzyme activity were improved in the 3% group. At the same time, some anti-freeze-related genes' (including ras homolog family member A (RHOA), heat shock protein 70 (HSP70), and small nuclear ribonucleoprotein polypeptide A (SNRPA1)) expressions were upregulated within the 3% DMA group relative to other groups. In conclusion, the 3% DMA group maintained higher post-thawed sperm quality than the other tested groups.

Seminal Bacterioflora of Two Rooster Lines: Characterization, Antibiotic Resistance Patterns and Possible Impact on Semen Quality.

This study aimed to characterize the bacterial profiles and their association with selected semen quality traits among two chicken breeds. Thirty Lohmann Brown and thirty ROSS 308 roosters were selected for semen quality estimation, including sperm motility, membrane and acrosome integrity, mitochondrial activity, and DNA fragmentation. The oxidative profile of the semen, including the production of reactive oxygen species (ROS), antioxidant capacity, protein, and lipid oxidation, were assessed as well. Moreover, the levels of pro-inflammatory cytokines, including tumor necrosis factor alpha (TNF-α), interleukins 1 and 6 (IL-1, IL-6) and C-reactive protein, as well as the concentrations of selected antibacterial proteins (cathelicidin, ß-defensin and lysozyme) in the seminal plasma were evaluated with the enzyme-linked immunosorbent assay. The prevailing bacterial genera identified by the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry were Citrobacter spp., Enterococcus spp., Escherichia spp. and Staphylococcus spp. While the bacterial load was significantly higher in the ROSS 308 line (p < 0.05), a higher number of potentially uropathogenic bacteria was found in the Lohmann Brown roosters. Antimicrobial susceptibility tests revealed a substantial resistance of randomly selected bacterial strains, particularly to ampicillin, tetracycline, chloramphenicol, and tobramycin. Furthermore, Lohmann Brown ejaculates containing an increased proportion of Escherichia coli presented with significantly (p < 0.05) elevated levels of TNF-α and IL-6, as well as ROS overproduction and lipid peroxidation. Inversely, significantly (p < 0.05) higher levels of ß-defensin and lysozyme were found in the semen collected from the ROSS 308 roosters, which was characterized by a higher quality in comparison to the Lohmann Brown roosters. In conclusion, we emphasize the criticality of bacteriospermia in the poultry industry and highlight the need to include a more complex microbiological screening of semen samples designated for artificial insemination.

The Synergistic Effects of the Combination of L-Carnitine and Lycopene on the Lycopene Bioavailability and Duodenal Health of Roosters.

The objective of this study was to investigate the impact of Lycopene and L-Carnitine, individually or in combination, on various physiological and molecular factors related to intestinal health and absorption ability in Roosters, such as intestinal morphology, serum biochemical parameters, genes involved in Lycopene uptake, nutritional transport genes, and tight junction genes. The findings of the study revealed that the combination of L-Carnitine and Lycopene supplementation had been found to increase the serum concentration levels of TP and ALB. Interestingly, the relative mRNA expression of genes responsible for Lycopene uptakes, such as SR-BI and BCO2, was higher in the LC group compared to other groups. Additionally, the expression of specific nutritional transport genes in the duodenum was significantly affected by both CAR and LC supplementation groups. The tight junction gene OCLN showed a significant increase in expression in the combination group compared to using either Lycopene or L-Carnitine alone. This study concludes that using Lycopene and L-carnitine in combination in poultry feed can potentially improve intestinal morphology and serum biochemical parameters, increase Lycopene bioavailability, improve nutrients uptake, and enhance the integrity of duodenal tight junctions in Roosters.

Short-Term Storage of Rooster Ejaculates: Sperm Quality and Bacterial Profile Differences in Selected Commercial Extenders.

Bacterial contamination of semen has become an important contributor to the reduced shelf life of insemination doses in the poultry industry, which is why antibiotics (ATBs) are an important component of semen extenders. Due to a global rise in antimicrobial resistance, the aim of this study was to assess the efficiency of selected commercially available semen extenders to prevent possible bacterial contamination of rooster ejaculates. Two selected extenders free from or containing 31.2 µg/mL kanamycin (KAN) were used to process semen samples from 63 healthy Lohmann Brown roosters. Phosphate-buffered saline without ATBs was used as a control. The extended samples were stored at 4 °C for 24 h. Sperm motility, viability, mitochondrial activity, DNA integrity and the oxidative profile of each extended sample were assessed following 2 h and 24 h of storage. Furthermore, selective media were used to quantify the bacterial load and specific bacterial species were identified with matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. The results indicate that semen extenders enriched with KAN ensured a significantly higher preservation of sperm quality in comparison to their KAN-free counterparts. Bacterial load was significantly decreased in diluents supplemented with ATBs (p ≤ 0.001); however, KAN alone was not effective enough to eradicate all bacteria since several Escherichia coli, Enterococcus faecalis, Enterococcus faecium and Micrococcus luteus were retrieved from samples extended in KAN-supplemented commercial extenders. As such, we may suggest that more focus should be devoted to the selection of an optimal combination and dose of antibiotics for poultry extenders, which should be accompanied by a more frequent bacteriological screening of native as well as extended poultry semen.

Research Note: Dietary supplementation with pyrroloquinoline quinone disodium (PQQ.Na2) improves oxidative status and semen quality in aging layer breeder roosters.

As the antioxidant capacity of sperm declines with age in roosters, the objective of the present study was to determine the effects of different levels of pyrroloquinoline quinone disodium (PQQ.Na2) on antioxidative and sperm quality parameters of aging layer breeder roosters. A total of ninety-six 63-wk-old Jinghong No. 1 layer breeder roosters were randomly assigned to 4 treatments (0, 0.5, 1, 2 mg/kg PQQ.Na2) for 6 wk. Antioxidant activity and semen parameters were assessed biweekly. The dietary administration of PQQ.Na2 significantly increased semen quality (semen volume, sperm motility, straightness, progressive motility, curvilinear velocity, straight-line velocity, and amplitude of lateral head displacement) and antioxidant capacity (T-SOD, GSH-Px, hydroxyl radical scavenging ability, and/or superoxide scavenging capacity) in seminal plasma in aging layer breeder roosters. Whereas, PQQ.Na2 supplementations significantly decreased malondialdehyde (MDA) concentration in seminal plasma in aging layer breeder roosters. Supplementation with 1 mg/kg dietary PQQ.Na2 as an antioxidant supplement could increase sperm quality and antioxidant activity of aging layer breeder roosters, while a higher dose (2 mg/kg) did not result in further increment.