Quercetin Reduces Inflammation and Protects Gut Microbiota in Broilers.

The aim of this study was to investigate the effects of quercetin on inflammatory response and intestinal microflora in broiler chicken jejuna. A total of 120 broiler chickens were allocated into 3 groups: saline-challenged broilers fed a basal diet (CTR group), lipopolysaccharide (LPS)-challenged broilers fed a basal diet (L group) and LPS-challenged broilers fed a basal diet supplemented with 200 mg/kg quercetin (LQ group). Our results showed that LPS significantly increased expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, IL-8, interferon (IFN)-γ, toll-like receptor (TLR)-4, Bax, Caspase-3 and diamine oxidase activity (DAO), and decreased expression of zona occludens-1 (ZO-1), Occludin and Bcl-2 in the jejunum, while dietary quercetin prevented the adverse effects of LPS injection. LPS injection significantly decreased the number of Actinobacteria, Armatimonadetes and Fibrobacteriae at the phylum level when compared to the CTR group. Additionally, at genus level, compared with the CTR group, the abundance of Halomonas, Micromonospora, Nitriliruptor, Peptococcus, Rubellimicrobium, Rubrobacter and Slaclda in L group was significantly decreased, while dietary quercetin restored the numbers of these bacteria. In conclusion, our results demonstrated that dietary quercetin could alleviate inflammatory responses of broiler chickens accompanied by modulating jejunum microflora.

Effects of k-carrageenan supplementation or in combination with cholesterol-loaded cyclodextrin following freezing-thawing process of rooster spermatozoa.

This experimental research purposely seeks to explore the effect of supplementing k-carrageenan (k-CRG) or CLC (cholesterol-loaded cyclodextrins) or the combined effect of k-CRG and CLC as supplements of antioxidants to an extender for rooster semen freezing. A total of 75 neat pooled ejaculates were collected twice a week from twenty-five (25) commercial line arbor acres broiler roosters (30 wks) during the experimental period. In each replicate, semen samples (n= 15, three ejaculates per rooster) were pooled and divided into nine equal aliquots, and each aliquot was diluted with one of the following extender supplemented with k-CRG, CLC, and k-CRG + CLC after which it was subjected to cryopreservation process using the "pellet" method. In study I, the supplementation of extenders with k-CRG was in five equal aliquots as follows; (0.2, 0.4, 0.6, 0.8) mg/mL and control group (k-CRG 0) mg/mL while in Study II, there was a combination of both k-CRG + CLC (0.4 mg/mL + 1.5 mg/mL, respectively), 0.4 mg/mL k-CRG, 1.5 mg/mL CLC and control group. Sperm quality parameters, endogenous antioxidant enzymes, lipid peroxidation (MDA) and ROS were all assessed after the freeze-thaw process. Our findings in study I indicated that at post-thaw, an optimum 0.4 mg/mL k-CRG supplementation in the extender improved semen quality parameters, endogenous enzymes, MDA and ROS in comparison to the control group. Interestingly prior to the freeze-thaw process, it was depicted in study II that combined k-CRG + CLC (0.4 mg/mL+1.5 mg/mL) inclusion in the extender provided maximum protection to sperm quality parameters, endogenous enzymes, MDA and ROS in comparison to 1.5 mg/mL CLC and control group at post-thaw. Besides, there was also a significant difference observed in the extenders supplemented with combined k-CRG + CLC (0.4 mg/mL +1.5 mg/mL) when compared to 0.4 mg/mL k-CRG for semen quality parameters and endogenous antioxidant enzymes (SOD, CAT, and GPx) but no significant difference was observed for MDA and ROS. Also, there was a significant difference observed in the extender supplemented with 1.5 mg/mL CLC when compared to the control group for semen quality parameters, SOD, CAT, and MDA but no significant difference for GPx and ROS at post-thaw. In conclusion, k-CRG at an optimal dosage of 0.4 mg/mL proved effective for improving post-thaw sperm quality but its combined addition k-CRG + CLC at an optimal concentration of (0.4 + 1.5) mg/mL in the extender provided greater protection to the rooster spermatozoa at post-thaw.

Quercetin supplemented casein-based extender improves the post-thaw quality of rooster semen.

The advantageous influence of quercetin (Q) supplementation in an extender has not yet been evaluated for rooster semen cryopreservation. This research was purposely conducted in order to assess the effect of different quercetin concentrations added into an extender on the sperm quality of the rooster subsequent to a freezing-thawing process. After the freezing-thawing process, spermatozoa quality parameters (membrane functionality, acrosome integrity, motility, viability, and abnormal morphology), endogenous enzymes (SOD, CAT, and GPx), mitochondrial activity, DNA fragmentation index, lipid peroxidation (MDA), and ROS were all evaluated. A total of 75 neat pooled ejaculates (3 ejaculates/rooster) were collected from 25 arbor acres roosters (24 wks) twice a week using abdominal massage technique, then divided into five equal aliquots and diluted with an extender containing different doses of Q (CS-Q) as follows: casein extender without Q (control only), casein extender containing 0.040 mg/mL quercetin (CS-Q 0.040), 0.020 mg/mL quercetin (CS-Q 0.020), 0.010 mg/mL quercetin (CS-Q 0.010), and 0.005 mg/mL quercetin (CS-Q 0.005). Our results depicted that adding to the extender with a 0.010 mg/mL Q enhanced (P < 0.01) sperm motility, membrane function, viability, mitochondrial activity, intact acrosome (P < 0.05), SOD (P < 0.001), CAT, and GPx (P < 0.01) compared to the control group at post-thaw. Compared to the control group and other treatment groups after the freeze-thawing process, the addition of 0.005 mg/mL Q into the extender also showed higher (P < 0.05) improvement in the quality of sperm parameters and a higher (P < 0.01) SOD and CAT but did not improve mitochondrial activity and sperm viability. In addition, there was a lower degree of DNA fragmentation index, lower (P < 0.05) lipid peroxidation and ROS in frozen-thawed sperm treated with 0.010 mg/mL and 0.005 mg/mL Q than in control and the other treatment groups. In addition, 0.020 mg/mL Q supplementation into the extender also reduced DNA fragmentation and improved GPx activity compared to the control group at post-thaw. Different concentrations of Q 0.010 and 0.005 mg/mL added to the extender reduced the percentage of abnormal spermatozoa compared to the other groups. The results of this study showed for the first time that the inclusion of an extender with a suitable quercetin concentration of 0.010 mg/mL improved the post-thawed quality of rooster semen.

Photoperiodic effect on the testicular transcriptome in broiler roosters.

Information about the effects of photoperiod on the testicular transcriptome of broiler roosters is limited. The aim of the present study was to explore the effect of different photoperiodic regimes on gene expression in the testes of broiler breeder roosters. One hundred and twenty Arbor Acres broiler breeder roosters aged 20 weeks were assigned to one of three groups (n = 40) and subjected to different photoperiodic regimes: control (CTR; 12.5 L:11.5 D), short day (SD; 8 L:16 D) and long day (LD; 16 L:8 D). After 4 weeks, the testes of 10 randomly selected birds from each group were dissected, sliced and haematoxylin-eosin stained. The testicular transcriptome of roosters from the SD and LD groups was determined by RNA sequencing (RNA-Seq), and the results were confirmed using quantitative real-time PCR. The seminiferous tubule area and sperm count increased significantly with the prolongation of photoperiod (p < .01). Additionally, the RNA-Seq results indicated that 387 genes were upregulated and 1,052 genes were downregulated in the LD group compared with those in the SD group. Several crucial genes involved in rooster testicular development and reproduction were also screened, including heat shock proteins 90, extracellular regulated protein kinases 1, phosphatidylinositol 3-kinase, adenosine 5'-monophosphate -activated protein kinase, BCL-6 and Smad3. The differentially expressed genes were enriched in the mammalian targets of rapamycin (mTOR), forkhead box (FoxO), transforming growth factor beta (TGF-ß) and insulin signalling pathway. In conclusion, a 16 hr photoperiod for 4 weeks increased the seminiferous tubule duct area and promoted spermatogenesis in the rooster's testicles, and the mTOR, FoxO, TGF-ß and insulin signalling pathways may be involved.

Antioxidative effect of melatonin on cryopreserved chicken semen.

This is a unique study because is the first time we are adding melatonin into an extender in order to determine its influence on cryopreserved chicken semen. The primary focus of our present study was to evaluate the influence of different concentrations of Melatonin on cryopreserved chicken semen. Semen samples were allocated into four treatments, being one control and three different combinations of antioxidants and after the freeze-thaw operation, the sperm motility, plasma membrane integrity, acrosome integrity, endogenous enzymes (GSH-Px, CAT, SOD), MDA and ROS of chicken spermatozoa were all evaluated. The collection of the semen samples was from 40 Arbor Acre roosters and this procedure was repeated twice a week and then mixed in an extender that contained different MEL treatments as follows: a diluent without MEL (control, M 0), a diluent comprising 0.125 mg/mL (M 0.125) 0.25 mg/mL, (M 0.25) and 0.5 mg/mL (M 0.5). It was revealed that the supplementation of the base extender with an optimal 0.25 mg/mL MEL led to a higher significant difference in the motility of chicken sperm (P < 0.01), higher acrosome integrity (P < 0.05) and a higher plasma membrane integrity (P < 0.01) when compared to the control group at post-thaw. Furthermore, when compared to the control group, 0.25 mg/mL MEL addition into the extender significantly enhanced the activity of endogenous enzymes (GSH-Px, CAT, and SOD) in the chicken spermatozoa at post-thaw (P < 0.05). Moreover, 0.5 mg/mL MEL supplementation into the extender enhanced the GSH-Px activity in the chicken spermatozoa when compared with the control group (P < 0.05) at post-thaw. In contrast, the addition of 0.25 mg/mL MEL into the extender resulted in a significantly lower MDA in comparison to the 0.125 mg/mL, 0.5 mg/mL MEL treatment group and the control group (P < 0.05). Also, compared to the control group, MEL concentration of 0.125 mg/mL and 0.5 mg/mL MEL into the extender resulted in a significantly low ROS concentration (P < 0.05) but the addition of 0.25 mg/mL MEL concentration resulted in a significantly lower ROS level when compared to the control group (P < 0.01). In summary, MEL improved the quality of cryopreserved chicken sperm quality by decreasing oxidative stress level and the most optimal concentration was 0.25 mg/mL.