Determination of percentage elongation at break and histopathology of skin from yankasa sheep experimentally infested with Amblyomma variegatum.

Bites of haematophagous ectoparasites cause mechanical injuries and histopathological changes in their hosts' hides and skins whose resultant leathers become unsuitable for certain leather products. The effects of tick bites on the wellbeing of their hosts are known, however, knowledge of their effects on the quality of leathers is scarce. This work investigated the effects of tick bites on the histopathology of skin and the percentage elongation at break (PEB) of shoe upper leathers produced from the skins of Amblyomma variegatum infested Yankasa sheep. A total of nine apparently healthy Yankasa sheep were selectively purchased from the open market and acclimatized for four weeks in the laboratory. Three animals in each of group 1 and 2 were infested with 40 nymphs and 20 adults of Am. variegatum respectively. Group three animals served as uninfested control. All animals were euthanized after the ticks were fully engorged and detached. Skin biopsies at tick attachment points and the uninfested control were taken from flayed skins and processed for histopathological examination. All skins were processed into finished leathers and their PEB determined. Histopathological studies revealed keratinization in all Am. variegatum infested sheep skins, while the un-infested control skins were normal. Mean PEB (%) of leathers were 21.41±3.33SE (nymphs), 36.73±4.44SE (adults) and 47.83±2.78SE (control). Bites of Am. variegatum cause histopathological changes in Yankasa sheep skins that significantly (p = 0.006) reduce the PEB of resultant leathers to less than the acceptable minimum standard of 40 % whose leathers are classified as rejects. In this study, skin of Yankasa sheep infested by nymphs and adults of Am. variegatum ticks resulted in low quality leathers that are unsuitable for standard leather products production and are also of low market value due to keratinization. Sustained efforts need to be undertaken to increase the awareness on the negative impact of tick bites on leather products by encouraging livestock farmers to engage in early treatment of animals infested with ticks.

Impact of road transportation on physiological and oxidative stress biomarkers in puppies: Beneficial effect of melatonin.

Transportation stress is complex and can affect the welfare and health of animals. The study was aimed at investigating the impact of road transportation on puppies and the beneficial effects of melatonin supplementation. Fourteen (14) apparently healthy Nigerian indigenous breed of dogs (puppies) divided into two groups, group I (control) and group II (pretreated with Melatonin at 10 mg/kg) were transported by road during the hot-dry season. Vital parameters; respiratory rate (RR), pulse rate (PR) and rectal temperature (RT) were taken before, during and immediately after commencement of the journey. Blood sample was also collected from each puppy before and immediately after the journey, part of which was used to analyzed for some hematological parameters and oxidative biomarkers such as the concentration of malondialdehyde (MDA) and reduced glutathione (GSH) and the activities of superoxide dismutase (SOD) and catalase (CAT). The result revealed that road transportation caused moderate to severe stress on the puppies as observed with the discomfort index (DI) (27.75-34.64 oC). The dry-bulb temperature during the study period was 33.23 ± 0.13 oC, while the relative humidity was 73.85 ± 0.60%. The RT, PR and RR also increased significantly (p < 0.05) during and immediately after the transportation compared to before commencement of the transportation. The result further revealed that total leucocyte counts and Neutrophil:Lymphocyte ratio (NLR) were elevated immediately after the transportation. The MDA concentration was also significantly (P < 0.05) elevated immediately after the transportation compared to before commencement in the control group. The activities of SOD and CAT and the concentration of GSH was lowered immediately after the transportation compared to before commencement. Supplementation with melatonin before the transportation ameliorated the stress posed by road transportation on the puppies as can be observed in the lowering of the elevated RT, PR and RR, total leucocyte count, NLR and MDA concentration. Pretreated with melatonin also increased the depleted activities of SOD and CAT, and the concentration of GSH immediately after the transportation. The results showed that road transportation is stressful for puppies and supplementation with melatonin mitigated the stress posed on the puppies, probably through the ability of melatonin to scavenge reactive oxygen species generated during the transportation. The results further showed that melatonin may be used to enhance the welfare of puppies subjected to road transportation under adverse thermal conditions.