Molecular insights on skewing of sex ratio in rabbits (Oryctolagus cuniculus) supplemented with dietary calcium and magnesium.

The effect of dietary calcium (Ca) and magnesium (Mg) supplementation on serum biochemical parameters, steroid hormones, gene expression, and the sex ratio was investigated in female New Zealand white rabbits. A total of 25 rabbits were allocated into five treatment groups: The control group was fed with regular pellet feed, whereas, treatment groups were supplemented with Ca and Mg: T1 (0.40% and 0.01%), T2 (0.60% and 0.02%), T3 (0.80% and 0.03%) and T4 (1.00% and 0.04%), respectively. The rabbits were subjected to three breeding cycles. The T3 group skewed towards females (65.33%) from all three breeding. There was elevated Ca concentration in T3 (15.26 ± 0.77 mg dL-1) and T4 (15.61 ± 0.82 mg dL-1) groups compared to the control. The concentration of estradiol was significantly high in T3 and T4 groups at 0.5 days post-coitus (dpc) and T2, T3 and T4 groups at 21dpc. Testosterone was significantly high in T4 group at 0.50 dpc and T2 and T4 group at 21dpc. The expression of 13 genes was studied in the oviduct. Genes such as OVGP1, CCT4, ANXA2 and TLR4 were up-regulated and positively correlated with the female sex ratio. The molecular functions and pathways of up-regulated genes were suggestive of their role in fertilization such as sperm selection, sperm storage, immune regulation, implantation and early embryonic development. The variations in the serum electrolytes, steroid hormones and gene expression might have an impact on the skewing process.

Organic Zinc and Copper Supplementation-Associated Changes in Gene Expression and Protein Profiles in Buck Spermatozoa.

Mineral supplementation has greater impact on male reproduction; however, the mechanism of action has not been studied in detail. The present study was aimed to deal with the lacuna in mechanism of action of mineral supplementation on improvement in sperm characteristics. A group of 40 bucks (aged 5 months) were assigned to 10 groups (4 in each group) based on their body weight and fed with concentrate mixture: basal roughage (minimal diet) in equal proportion to all the bucks. Among the 10 groups, one was considered as control, without any additional mineral supplementation, and the remaining 9 were treatment groups (3 groups each in Zn, Cu, and Zn + Cu). In treatment groups, organic Zn was fed in three different doses as 20, 40, and 60 mg/kg DM; organic Cu was fed in three different doses as 12.5, 25, and 37.5 mg/kg DM; and organic Zn + Cu was combinedly supplied as 20 + 12.5, 40 + 25, and 60 + 37.5 based on their mg/kg DM for 8 months period. The neat semen samples were processed for spermatozoal gene (stress- NOS3, HSP70, HIF1A; fertility- MTF1, MTA1, TIMP2, TNFa, and EGFR) expression studies through qRT-PCR and protein profile changes through single- and two-dimensional gel electrophoresis. Significantly, the stress-responsive genes were downregulated, and fertility-related genes were upregulated in treatment groups. A significant correlation had been noticed among the genes studied: HIF1A with MTA1 (P < 0.05) and MTF1 with EGFR, TIMP2, TNFa, and NOS3 (P < 0.01) respectively. The organic Zn and Cu feeding modulated the expression of stress- and fertility-related genes and protein abundance, thereby improved the sperm characteristics.

Organic Zn and Cu supplementation imprints on seminal plasma mineral, biochemical/ antioxidant activities and its relationship to spermatozoal characteristics in bucks.

This experiment was conducted to study the effect of mineral supplementation on seminal plasma minerals level, biochemical constituents and total antioxidant capacity of Osmanabadi bucks. The study comprised of forty healthy bucks, aged five months were randomly assigned to ten groups (n = 4 per group). The control group was fed with a basal diet without any additional mineral supplementation. In addition to basal diet, treatment bucks were supplemented with three graded doses of organic Zinc (Zn) as 20, 40 and 60 mg/kg dry matter (DM); organic Copper (Cu) as 12.5, 25, 37.5 mg/ kg DM and combination of Zn + Cu as Zn20+Cu12.5, Zn40+Cu25, Zn60+Cu37.5 mg /kg DM basis respectively. Minerals were supplemented for 8 months and the separated seminal plasma used for analysis of minerals, biochemical profile, total antioxidant capacity (TAC), lipid peroxidation (LPO), and protein carbonylation (PC). In treatment groups, significantly lower LPO and PC were observed, except Zn60 and Zn60+Cu37.5, where higher malondialdehyde (MDA) (P < 0.05) formed. The TAC was relatively higher (P < 0.05) in Zn20, Zn40, Cu12.5 and Zn60+Cu37.5 than control. The minerals and biochemical parameters were significantly altered and positive relationship was observed among them. From this study, it was concluded that supplemented minerals changed the seminal plasma minerals profile (Zn- 7-13; Cu- 0.5-1.9 mg/L), reduced the stress (LPO and PC of control Vs treatment as 0.3 Vs 0.1 nmol/ml and 25.7 Vs 4.3 nmol protein carbonyl/mg protein), which improved the sperm quality in Zn40, all Cu treatments and Zn60+Cu37.5 groups respectively.

Impact of arsenic(V) on testicular oxidative stress and sperm functional attributes in Swiss albino mice.

The arsenic (As) is a multi system effector including reproduction. The present study examined the association of graded doses of As(V) on testicular microenvironment and sperm function in mice. Thirty-six adult male mice were randomly assigned to six groups (n = 6). Group A served as control without test chemical. The groups B, C, D, E, and F were administered graded doses of 10, 25, 50, 100, and 200 ppm As(V), respectively, through drinking water for 40 days. A dose-dependant significant (P < 0.05) decrements were observed in epididymal sperm kinematic attributes (progressive motility, rapid, fast progressive, VCL, VSL, VAP, LIN, STR, WOB and TYPE A (STR >80 %, ALH 2.5 µm) by CASA), viability, plasma membrane functional integrity, and mitochondrial membrane potential which were associated with insignificant decrease in serum testosterone levels. The histoarchitectural studies of testes showed progressive loss of spermatozoa concentration in the seminiferous tubules as the As(V) dose increased. The mice exposed to As(V) had an increase in the As accumulation, protein carbonylation, and lipid peroxidation levels associated with alterations in SOD, CAT, and GST activities in the testes. In conclusion, higher doses of As(V) (more than 50 ppm) were found to be testicular toxicants which impaired semen quality by inducing oxidative stress in the testicular microenvironment.