Impact of heat stress on follicular size, oestradiol concentration and oestrus expression in Nigerian Zebu cows

The study was conducted to evaluate the effect of heat stress on follicular size, oestradiol concentrations and oestrus expression in different seasons on Zebu cows. Twelve (n=12) matured, Zebu cows were utilized for over a year. The year was divided into 3 phases. Ambient temperature, relative humidity and rectal temperature were determined using. Cows were synchronized for oestrus. Ultrasonic follicular studies were carried out daily. Blood samples were collected after administration of a second dose of PFG2α to assess serum concentration of oestradiol. The enzyme-linked immunosorbent assay technique was used to determine the concentration of oestradiol. Oestrus activities were monitored by visual observation. Follicle diameters at 24 hr were lower (P< 0.05) in the cold, dry season (6.34± 0.68 mm) than hot dry (8.09±0.52 mm) and the rainy season (8.62±0.9 mm). At 72 hr, follicular diameters were significantly higher P<0.05 in the hot, dry season (17.01±1.41 mm) than cold dry (12.90±1.22 mm) and the rainy season (12.08±0.82 mm). Time to peak of oestradiol concentrations was shorter P<0.05 in the cold, dry season (31.50±5.41 hr), followed by a hot, dry season (35.42±4.25 hr) and then rainy season (52.25±7.08 hr). The amplitude of oestradiol was higher P<0.05 in the cold, dry season (39.13±5.27 pg/mL) than hot dry (19.50±2.52 pg/mL) and rainy seasons (17.63±1.89 pg/mL). Durations of proestrus oestradiol surges were significantly higher P<0.05 in the rainy season (40.88±7.10 hr) followed by a hot, dry season (35.50±7.71 hr) and then cold dry season (24.25±3.27 hr.). The total number of mounting activities for two hr. was higher P<0.05 in the cold, dry season (7.6±0.93/hr) followed by rainy season (6.2±1.28/hr) and then hot dry season (4.4±0.81/hr). In conclusion, the study showed that heat stress affected oestrus expression by lowering the number of mounts per hour, increasing follicular size and reducing oestradiol concentration of these cows

Optimal nutrition, a key to addressing reproductive performance in Nigerian local turkey toms

The Nigerian local turkey has the potential to augment the supply of poultry protein in the country and across the region. However, the fecundity of the breed is low due to neglect and lack of improvement. This work is therefore aimed at shedding some light in some reproductive indices of the local turkey under optimum nutrition. A group of fifteen toms and nine hens were used in this study. The males were grouped into three groups of five and placed on varying levels of protein, 12% CP, 16% CP and 20% CP for groups 1, 2 and 3 respectively. Semen samples were collected and analysed twice weekly for thirteen weeks. Ejaculate volume, semen concentration, semen PH, gross and individual motilities, live and dead sperm and sperm morphology were investigated and recorded. Data were summarized as mean ± SEM (Standard Error of the Mean). The toms in groups 3 had significantly (P < 0.05) higher ejaculate volume 0.29 ± 0.03 mls and semen concentration7.766 ± 0.612 x109 than groups 1 and 2. The fertilizing ability, which was assessed through in vivo and in vitro sperm penetration assays revealed significantly higher number of sperm penetration holes (P < 0.05) in Groups 2 and 3, 160.97 ± 8.084 and 172.83 ± 7.647 (in vivo); 187.96 ± 8.121 and 189.16 ± 6.446 (in vitro) respectively. The local turkey toms could parallel their exotic counterpart under optimum environment, without the need for genetic hybridization and that 20% CP had more positive influence on the semen quality and fertilizing ability of indigenous Nigerian turkey toms followed by 16% CP with 12% CP exerting the least positive influence.Keywords: Artificial Insemination, Crude protein, Reproduction, Semen, Turkey tom

Melatonin and garlic cytoprotective-ameliorative effects on dibutyl phthalate intoxication on sperm DNA and testicular biomakers of rabbits

The study investigated the cytoprotective and ameliorative effects of melatonin and Allium sativum (garlic) on dibutyl phthalate (DBP)-induced oxidative stress, its impact on sperm DNA integrity and testicular oxidative stress biomarkers. Forty two rabbit bucks were randomly divided into 7 groups of 6 bucks each labeled as A, B, C, D, E, F and G: The treatment were as follows: A (served as negative control, received olive oil for 16 weeks); B (served as positive control, exposed to DBP for 16 weeks, no treatment); C (given melatonin for 8 weeks, thereafter DBP for 8 weeks); D (administered garlic for 8 weeks, thereafter DBP for 8 weeks); E (exposed to DBP for 8 weeks, thereafter melatonin for 8 week); F (exposed to DBP for 8 weeks, thereafter garlic for 8 weeks); and G (exposed to DBP for 8 weeks, thereafter melatonin + garlic for 8 weeks). Ejaculated semen was collected on the last day (112th) using artificialv vagina for rabbit and pooled for each group was used for sperm DNA fragmentation index (SDFI) determination, rabbits were sacrificed and the testes harvested for determination of superoxide dismutase activity, reduced glutathione and malondialdehyde concentration. Results showed a significant increase (P = 0.0018) in the mean SDFI in group B (78.20 ± 4.72), compared to other groups. A significant increase (P ≤ 0.0001) in superoxide dismutase activity, increase reduced glutathione concentration and decrease malondialdehyde concentrations in the treatment groups compared to the DBP exposed group without treatment (group B) were observed. Melatonin and garlic demonstrated cytoprotective and ameliorative effects against DBP-induced oxidative stress in rabbit bucks. Keywords: Dibutyl phthalate, Garlic, Melatonin, Sperm DNA, Testicular biomarker

Patency and Clinico-Haematological Pathologies Sequel to Trypanosoma brucei and Trypanosoma evansi Induced Infections in Yankasa Sheep I

Trypanosomosis remains one of the most deadly protozoan diseases that pose a significant impact on livestock health in the tropics. Sixteen (16) rams aged between 24 to 30 months and weighed between 22-25kg were acclimatized under standard animal housing  conditions. Twelve (12) of the sheep deemed fit and healthy were randomly divided into four groups (I, II, III, and IV) of three sheep each. Each sheep in groups I and II was inoculated intravenously with 2 mL containing 2 X 106 trypomastigote forms of Trypanosoma brucei and Trypanosoma evansi, respectively. While group III, each sheep received 2 mL containing 2 X 106 mixed inoculums of T. brucei and T. evansi (50% each by volume of the infective inoculums). Sheep in group IV served as the non-infected control. Post-infection animals were monitored for 14 weeks for parasitaemia, clinical signs, and haematological pathologies. The patent infection became evident in groups I, II, and III between 5-21 days post-infection with average patency of 7, 20, and 8.5 days respectively. The infection was characterized by intermittent pyrexia with a significant decrease (p< 0.001) in mean weekly packed cell volume (PCV),  haemoglobin concentration (Hb), live weight gain, plasma protein, which significantly decreased (p< 0.001) in all the infected groups. Pearson’s correlation (r) indicates a strong positive correlation (r= 0.991) between parasitaemia and pyrexia, and principal component analysis (PCA) biplot increased the predictabilities of these two indices as the major precursors in the progression of the trypanosomes pathogenesis in sheep. Keywords: Trypanosomosis; Patency; Clinico-haematological pathologies; Trypanosoma brucei; Trypanosoma evansi; Yankasa shee

Melatonin and Allium Sativum (Garlic) Protect Dibutyl Phthalate Influence on Spermiogram of Rabbit Bucks

This study was designed to evaluate the effects of melatonin and Allium sativum (garlic) on  dibutyl phthalate (DBP) influence on  spermiogram of rabbit bucks. Forty two (42) rabbit bucks were used for this study, bucks were randomly divided into 7 groups of 6 bucks each. Group A was administered olive oil for 16 weeks, group B (olive oil + DBP for 16 weeks), group C (melatonin for 8 weeks, then olive oil + DBP for another 8 weeks), group D (garlic for 8 weeks, then olive oil + DBP for another 8 weeks), group E (olive oil + DBP for 8 weeks, then melatonin for another 8 week), group F (olive oil + DBP for 8 weeks, then garlic for another 8 weeks) and group G (olive oil + DBP for 8 weeks, then melatonin and garlic for another 8 weeks). The observation period lasted for 120 days, during which semen samples were collected weekly between the hours of 8.00 am to 10.00 am using artificial vagina (AV).There were significant differences (P<0.05) in mean reaction time, semen volume, sperm motility, sperm concentration, percentage live spermatozoa and percentage abnormal morphology between DBP exposed groups and treatment groups. Conclusion, DBP has adverse effects on spermiogram but administration of melatonin and garlic has promising protective effects than therapeutic effect on rabbit bucks. Key words: Melatonin; Allium sativum; Dibutyl phthalate; Spermiogram; Rabbit Buck

Clinicopathological and Microscopic Features of Trypanosoma brucei and Trypanosoma evansi Induced Infections in Sheep II

The present study elucidates further on clinical, gross, and microscopic pathologies induced by single or mixed infections with  Trypanosoma evansi and Trypanosoma brucei in sheep. Briefly, the experimental animals were divided into four groups of three  animals each. Animals in each group were either infected with T. brucei, T. evansi, mixed (T. brucei and T. evansi), or noninfected. Animals were observed for clinical, gross, and microscopic pathologies for 98 days (14 weeks). The clinical pathologies observed included loss of body condition, pale ocular mucus membrane, rough hair coat, scrotal oedema, scrotal degeneration, emaciation, and death. At necropsy, macroscopic or gross lesions included very pale and anaemic carcass composition, congested and pneumonic lungs with severe haemorrhages, serous atrophy of intestinal and body fats, lymphadenopathy, splenomegaly, and hepatomegaly. Microscopic lesions observed in the testes, spleen, liver, lungs, lymphoid, heart, and brain tissues of infected sheep were varied and included swollen kidney with renal tubular degeneration, the proliferation of lymphocytes at the germinal centers of the spleen, degeneration of the bronchioles, severe testicular degeneration with a reduction in the number of spermatogenic cell layers,  degenerated Leydig and Sertoli cells with loss of sperm reserves in the seminiferous lumen, congested liver with sinusoidal spaces and the proliferation of monocytes and lymphocytes. The results indicate that trypanosomosis due to experimental T. brucei, T. evansi, or mixed infections may be an important cause of various grades of tissue and organ pathologies in sheep in trypanosome-endemic areas. Keywords: Trypanosomosis; Clinico-pathological and microscopic features; Trypanosoma brucei; Trypanosoma evansi; Mixed  infections; Shee

Haematological values of cows during third trimester of pregnancy and early lactation in settled cattle herds in Zaria, Northern Nigeria 1*

The haematological values of 176 cows during third trimester of pregnancy and early lactation in nine settled cattle herds in Zaria, Northern Nigeria, were studied. The total mean values of total protein (TP), packed cell volume (PCV), haemoglobin (Hb), red blood cell (RBC) and white blood cell (WBC) during pregnancy and early lactation did not differ significantly (P≥0.05) while neutrophil, lymphocyte, monocyte and eosinophil values differed significantly (P <0.05). Neutrophil and lymphocyte values during early lactation were higher than those during third trimester of pregnancy, while monocyte and eosinophil values during third trimester of pregnancy were higher than those of early lactation. The herds mean haematological values closely resembled those of the total mean values. The herds mean values of TP, PCV, Hb, RBC and WBC during third trimester of pregnancy and early lactation did not differ significantly (P <0.05) except in one herd (VIII) where the early lactation value was significantly (p <0.05) higher. In some herds, the mean values of neutrophil, lymphocyte and monocyte during third trimester of pregnancy were significantly (p <0.05) higher than those of early lactation while in others, they were significantly (p <0.05) lower. The mean values of eosinophil during lactation were significantly higher than those of third trimester pregnancy in all the herds. This study has provided reference haematological values of cows that may be safely assumed to be adequate and consistent with normal health and metabolic state during third trimester of pregnancy and early lactation. The study has also confirmed the significant effect of herd factor on haematological parameters of cows