Chlorella vulgaris supplementation effects on performances, oxidative stress and antioxidant genes expression in liver and ovaries of New Zealand White rabbits.

Oxidative stress is an exclusive biochemical complication affecting reproduction; hence, dietary antioxidant supplementation for its attenuation is a required nutrition - reproduction improvement strategy. On this background, Chlorella vulgaris (a natural antioxidant) was supplemented to grower female rabbits to maturity. The rabbits were thirty-five in number randomly distributed into five experimental groups in a completely randomized design. Control group was fed only basal feed while treatment groups were fed diets containing 40 %, 60 %, 80 % and 100 % Chlorella vulgaris biomass as T1, T2, T3 and T4 respectively at 500 mg per animal body weight (kg) along with the basal feed daily. Performance records were obtained, blood was collected, and at the end uterus, ovaries and liver were removed from sacrificed animals for analysis. Serum, uterus and liver oxidative stress status were determined while RNA isolated from liver and ovaries samples were used for antioxidant genes expression analysis. Oxidative stress status and antioxidant enzymes activities were determined using chemical assays while antioxidant gene expression levels were determined using real-time quantitative PCR system. There was significant difference in feed intake (p < 0.014), final body weights (p < 0.008), empty carcass weights (p < 0.001) and commercial carcass weights (p < 0.001) of the rabbits as results of the microalgae supplementation. There was also significant difference in malondialdehyde (MDA) concentrations (p < 0.050), total antioxidant capacity (TAC) (p < 0.050) and protein carbonyl (PCO) concentrations (p < 0.050) due to the supplementation of the microalgae; in addition, supplementation of the microalgae significantly improved activities of superoxide dismutase (SOD) (p < 0.050), catalase (CAT) (p < 0.050) and reduced glutathione (GSH) concentration (p < 0.050). Furthermore, there was significant difference in relative expression of primary antioxidant genes sod1 (p < 0.050) and gpx1 (p < 0.050); however, there was no significant difference in relative expression of bre (p > 0.050) and ucp1 (p > 0.050). The study concluded from the outcomes stated above that supplementation of microalgae Chlorella vulgaris improved performances of rabbits through attenuation of oxidative stress, enhancement of antioxidant enzymes activities as well as up-regulation of primary antioxidant genes. Hence, it was recommended as dietary supplement for protection against oxidative stress and improved productivity in rabbits and other food producing mammalian species. In addition, further studies into assessment of its effects on expression of transcripts and immune modulation genes in rabbits and other animals is warranted as future studies in order to established its potential as beneficial nutraceutical for animals and human.

Organic Zn and Cu interaction impact on sexual behaviour, semen characteristics, hormones and spermatozoal gene expression in bucks (Capra hircus).

The reproductive performance during the transition from prepubertal to pubertal stage was evaluated in Osmanabadi breed bucks supplemented with organic Zinc (Zn) and Copper (Cu). A total number of 40 bucks aged 20 weeks were randomly assigned to 10 groups (each n = 4). The control group was maintained with basal diet, without any additional mineral supplementation. The treatment groups were supplemented with graded doses of organic Zn (Zn 20 mg, Zn 40 mg and Zn 60 mg), Cu (Cu 12.5 mg, Cu 25 mg and Cu 37.5 mg) and a combination of Zn + Cu (Zn 20 mg + Cu 12.5 mg, Zn 40 mg + Cu 25 mg and Zn 60 mg + Cu 37.5 mg), respectively for a period of 26 weeks (up to the age of 46 weeks). Sexual behaviour and scrotal biometry were recorded periodically. Blood and semen samples were collected and processed for LH estimation in blood plasma, and testosterone, T3 and T4 hormones in the seminal plasma. The mounts with ejaculation were observed earlier (P < 0.05) in the treatment bucks (from 38th week of age) than the control group (43rd week onwards). A positive correlation was observed between blood plasma LH and testosterone with total mounts (r = 0.31, P < 0.05; r = 0.51, P < 0.01) and mounts without ejaculation (r = 0.40, P < 0.01; r = 0.52, P < 0.01). A negative correlation between T4 with sperm number per ejaculation (r = -0.31, P < 0.05) and sperm concentration (r = -0.35, P < 0.05) had been noticed. Different doses of minerals showed positive interaction (P < 0.05) with sperm functional and behavioural characteristics. The spermatozoal gene expression of ODF2 and ZCCHC6 were significantly influenced by the mineral supplementation in all doses. The ZCCHC6 gene expression was positively correlated with testosterone (r = 0.50, P < 0.001) and sperm number per ejaculation (r = 0.42, P < 0.001), and ODF2 gene with T3 hormone (r = 0.34, P < 0.05). The present study indicates that the diet supplemented with organic trace minerals cause intense sexual behaviour, enhancement in sperm number per ejaculate, total motility, spermatozoal genes expression and altered LH, testosterone and T4 hormones.

Advancement of puberty and enhancement of seminal characteristics by supplementation of trace minerals to bucks.

Attainment of puberty in animals is dependent on their age, body weight, nutritional status, genetic and environmental conditions. Nutritionally, organic minerals are suggested to improve semen production, sperm motility and male fertility. In this context, role of organic zinc (Zn) and copper (Cu) in advancing male puberty and semen characters in Osmanabadi goats were studied. Forty one (n = 41) bucks (Aged 5 months) were divided into ten groups and the dietary treatments comprised of a control group (basal diet; without additional trace mineral supplementation) and nine treatment groups that received, in addition to the basal diet, various doses of trace minerals (mg) on per kg dry matter basis, organic Zn as low Zn20, medium Zn40 and high Zn60, organic Cu as low Cu12.5, medium Cu25, high Cu37.5 and combination of organic Zn + Cu as low Zn20 + Cu12.5, medium Zn40 + Cu25, high Zn60 + Cu37.5, respectively fed for a period of 8 months. Bucks fed organic trace minerals reached puberty 28-35 days earlier than control group. In addition, improvement (P < .01) in testosterone hormone (ng/ml) levels (control: 1.63 ± 0.07 VS Zn60: 2.54 ± 0.02; Cu12.5: 6.17 ± 0.05; Cu25: 3.01 ± 0.04; Cu37.5: 2.39 ± 0.06; Zn20 + Cu12.5: 1.94 ± 0.02; Zn60 + Cu37.5: 2.44 ± 0.16 at 240 days), semen production capacity (sperm concentration, volume, mass motility) and semen quality (higher progressive motility, velocity, sperm membrane integrity and acrosome integrity) were observed in supplemented groups (P < .05) than the control bucks. The present study demonstrated that, additional feeding of organic Zn and Cu to growing male goats advanced onset of puberty and improved quantitative and qualitative semen characteristics. The results also implied that the organic Cu had a significant effect on overall performances of bucks as compared to Zn alone or Zn and Cu in combination.

Organic zinc and copper supplementation on antioxidant protective mechanism and their correlation with sperm functional characteristics in goats.

Trace minerals feeding had significant effects on sperm production and fertility with better absorption and proper utilization within the body for optimum reproductive function. Several studies have shown that more influenced trace elements in the diets of animals are copper (Cu) and zinc (Zn). Bucks showing deficiency of this mineral might affect the quality of semen production which in turn would affect the fertility. This experiment was thus designed to test the effects of organic Cu and Zn supplementation on antioxidants enzyme activities and sperm functional attributes in fresh semen of bucks. Forty bucks (n = 40, Aged 5 months) were assigned to ten groups of four animals in each group, supplemented (for a period of 8 months) with different levels of organic Zn: 20 mg (T2), 40 mg (T3) and 60 mg (T4), organic Cu: 12.5 mg (T5), 25 mg (T6), 37.5 mg (T7) and combined organic Zn and Cu: 20 + 12.5 mg (T8), 40 + 25 mg (T9), 60 + 37.5 mg (T10), respectively, per kg dry matter and no additional mineral diet (control; T1). One hundred and sixty semen samples were collected through electro-ejaculator and analysed for sperm quantity, quality, acrosome intactness and plasma membrane integrity and correlated with the catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase enzyme activities in seminal plasma. The results indicated organic Cu and zinc supplemented bucks produced more sperm cells, had higher sperm concentrations, maintained higher (p < .01) sperm livability, plasma membrane and acrosome integrities, more motility and velocity. The increased antioxidant enzyme activities, reduced oxidative stress and lowered lipid peroxidation were positively correlated (p < .05) with the sperm functional attributes. In conclusion, organic Cu and Zn supplement to male goats showed protective roles against oxidative damage and maintained better fresh semen characteristics.