Alexander B. Adelaiye

Erythrocyte osmotic fragility of pigs administered ascorbic acid and transported by road for short-term duration during the harmattan season

The experiment was carried out with the aim of investigating the effect of an antioxidant ascorbic acid on erythrocyte osmotic fragility of pigs transported by road for 4 h during the harmattan season. 16 pigs administered with ascorbic acid at the dose of 250 mg/kg per os and individually served as experimental animals and 13 others administered orally with sterile water were used as control animals. The animals were then transported for 4 h at a speed of 40 - 50 km/h covering a distance of 140 km. Blood samples for erythrocyte osmotic fragility determination which was done using standard procedure, were taken early in the morning a day before transportation, immediately after and a week after transportation. Erythrocyte osmotic fragility decreased significantly (P < 0.05) at NaCl concentration of 0.85, 0.80 and 0.70% in both experimental and control pigs following road transportation and the difference in the post-transportation values was higher (P < 0.05) in experimental compared to control pigs. The results indicated that ascorbic acid protected the integrity of the erythrocyte membrane in experimental pigs administered ascorbic acid following road transportation as demonstrated by lower percentage haemolysis immediately after road transportation and thus may alleviate the risk of increase in haemolysis due to road transportation stress in pigs during the harmattan season.

Seasonal, sex and live weight variations in feed and water consumptions of adult captive African Giant rats (Cricetomys gambianus, Waterhouse-1840) kept individually in cages.

Adult African Giant rats (Cricetomys gambianus, Waterhouse) (AGRs) (n = 231) of both sexes (117 bucks, 114 does) were live-trapped in the wild in Zaria, Nigeria. Live weight (LW), daily feed consumption (FC) and water consumption (WC) of the AGRs were measured during the cold-dry (CDS), hot-dry (HDS) and rainy (RS) seasons for 2 years with the aim of determining seasonal, sex and LW variations. Feed consumption was significantly different (p < 0.001) between all the seasons, with the lowest mean value recorded during the HDS, while the highest was obtained during the RS. Water consumption was also lowest (p < 0.001) during the HDS but did not differ significantly (p > 0.05) between the CDS and RS. Both feed and water consumptions were higher (p < 0.01) in the males (bucks) than the females (does) during the CDS and HDS, but the sex difference was not significant (p > 0.05) during the RS. Feed consumption correlated positively (p < 0.0001) with WC and relative humidity, but negatively (p < 0.0001) with LW, ambient temperature and heat index. In conclusion, both feed and water consumptions in AGRs decrease with increased seasonal heat and adult LW and are lower in does than in bucks during the dry seasons (CDS and HDS). Intervention may be indicated during the HDS to improve feed and water consumptions for optimal performance of the AGRs.

Quantitative changes in gastric mucosal glycoproteins: effect of cholinergic agonist and vagal nerve stimulation in the rat

The role of the vagus nerve and cholinergic mechanisms in the control of the rat gastric mucin and protein (PROT) release in vivo was investigated. Under urethane anaesthesia (1.25 g kg−1), the rats had their gastric lumen perfused with saline. Mucus secretion was measured as a function of adherent mucus on the mucosa surface and the luminal content of sialic acids (SIA), galactose (GAL), pyruvate and PROT. Electrical stimulation of the vagi significantly increased the levels of mucus (3.23 ± 025 μg g−1 tissue, P < 0.05), free sialic acid (FS) (0.18 ± 0.04 mg mL−1, P < 0.05) and PROT (0.25 ± 0.003 mg mL−1, P < 0.05) when compared with control animals. Bilateral cervical vagotomy had no significant effect on adherent mucus or basal levels of PROT, SIA and GAL (P > 0.05) with respect to the control. In both vagotomized and vagal intact animals, the cholinergic agonist (carbachol, 200 mg kg−1) significantly increased PROT, adherent mucus and FS (P < 0.05) and decreased bound sialic acid (P > 0.05). There were no visible haemorrhagic streaks on the gastric mucosa of vagotomized, vagal intact and carbachol‐treated animals. The results suggest that vagus nerve does not exert a tonic control on gastric glycoprotein secretion in vivo and that cholinergic effect on the mucus secreting cells may be implemented via the intrinsic nerves of the enteric nervous system.

Influence of co-administration of vitamins A and E on diurnal variation in rectal temperature of Black Harco pullets during the hot-dry season

Experiments were performed with the aim of determining the influence of vitamins A and E on the fluctuations in rectal temperature (RT) of Black Harco pullets during the hot-dry season. The RT of 29 experimental and 20 control pullets were measured every hour from 06:00 to 19:00 hours for three days. The experimental pullets were administered vitamins A and E orally at 1200 IU/kg and 30 mg/kg, respectively. The control pullets were given water only. The lowest hourly RT of 41.03 ± 0.03°C was obtained in experimental pullets at 06:00 h, while the highest value of 41.23 ± 0.04°C was recorded at 18:00 h (P < 0.001). In control pullets, the RT rose significantly from 41.00 ± 0.04°C at 06:00 h to a maximum value of 41.61 ± 0.04°C at 15:00 h (P < 0.001). It is concluded that vitamins A and E decreased the thermally stressful effect of the hot-dry season, and may enhance the productivity and health of pullets during the season.

Evaluation of physiologic pain in relation to pain substances in healthy subjects

This study was aimed at finding a relationship between pain modulators in the blood and physiological pain in apparently healthy Nigerians. It also aimed at establishing a pilot study for finding reference values for plasma levels of substance P, serotonin and tryptophan for the first time among Nigerians. Volunteers were made up of 110 residents of Abuja, aged between 21 and 50 years. Cold pressor test was used to induce pain assessing pain intensity, threshold and tolerance. ELISA was used to assay for plasma substance P, serotonin and tryptophan. Pain parameters from cold pressor test were correlated with plasma pain modulators measured. Results from cold pressor test revealed pain intensity to be 5.79±0.25cm, pain threshold 28.77±2.32s and pain tolerance 143.62±24.39s. Blood plasma level of substance P was 116.52±20.53pg/mL, serotonin 454.18±30.16ng/mL and tryptophan 12.77±0.67μg/mL. There was negative correlation between pain threshold and plasma substance P, pain tolerance and plasma substance P and pain threshold and plasma serotonin. There was however a positive correlation between pain intensity and plasma serotonin. In conclusion, the regression formulas may aid in using cold pressor test to predict blood substance levels of the measured pain modulators in a low resource setting like Nigeria where ELISA test is very expensive.

Mechanism of Action of Tephrosia vogelii Leaf Extract on Isolated Rabbit Jejunum

ABSTRACT An investigation was carried out on the isolated rabbit jejunum using the crude methanolic leaf extract of Tephrosia vogelii Hook. f. (Fabaceae) with the aim of determining the possible mechanism by which it increases the contractions of intestinal smooth muscle. Atropine concentration-dependently (2.0 × 10−10–6.4 × 10−9 g/ml) blocked the effect of the extract (2.0 × 10−4–4.0 × 10−4 g/ml) on both the frequency and amplitude of contraction of the isolated tissue (n = 4). Similarly, nifedipine concentration-dependently (4.0 × 10−9–8.0 × 10−6 g/ml) blocked the effect of the extract (2.0 × 10−4–4.0 × 10−4 g/ml) on both the frequency and amplitude of contraction of the tissue (n = 4). The extract, apparently, acted through muscarinic cholinergic receptors present in the tissue, and this action probably involved the mobilization of extracellular calcium ions.