Seventy day safety assessment of an orally ingested, l-glutamine-containing oat and yeast supplement for horses

Ameliorative effects of L-glutamine on haematological parameters in heat-stressed Red Sokoto goats

The aim of the study was to evaluate haematological responses in Red Sokoto goats (RSGs) administered with L-glutamine during the hot-dry season. Experimental animals included 28 clinically healthy RSGs divided into treated group (n = 14); each administered L-glutamine at 0.2 g/kg body weight, dissolved in 10 mL distilled water, and control group (n = 14); each administered 10 mL distilled water, per os once daily for 21 days. The ambient temperature and relative humidity recorded daily for 4 weeks were used to calculate the temperature-humidity index. Three millilitres of blood sample was collected from each goat by jugular venipuncture for haematology, while rectal temperature (RT), heart rate (HR) and respiratory rate (RR) were also measured once weekly at weeks 0 (before), 1, 2, 3 (during) and 4 (after L-glutamine administration). The haematological, RT, HR and RR data obtained weekly were analysed using repeated-measures one-way ANOVA, followed by Tukey's post-hoc test to evaluate differences between periods, and between treated and control groups. The PCV, haemoglobin concentration and RBC count were higher (P < 0.05) in the treated group compared to the control group during the period of L-glutamine administration. These differences were sustained till week 4. Beginning from week 1 of the study, the total leucocyte count in treated group (10.10 ± 0.25 × 10³/μL) was higher (P < 0.05) than the count in control group (7.23 ± 0.41 × 10³/μL), this trend was also maintained throughout the study. The neutrophil:lymphocyte ratio during weeks 3 and 4 of the experiment was lower (P < 0.05) in the treated compared to the control group. RT was lower (P < 0.05) in treated group than the control group. In conclusion, L-glutamine administration ameliorated the adverse effects of heat stress on the haematological parameters in RSGs during the hot-dry season.

Effects of L-glutamine on rectal temperature and some markers of oxidative stress in Red Sokoto goats during the hot-dry season

The experiment investigated the ameliorative effects of L-glutamine administration on rectal temperature (RT), erythrocyte osmotic fragility (EOF), serum antioxidant enzyme activities and malondialdehyde (MDA) concentration in Red Sokoto goats during the hot-dry season. Twenty eight healthy Red Sokoto goats, comprising 14 experimental (administered 0.2 g/kg of L-glutamine dissolved in 10 mL of distilled water, once daily for 21 days) and 14 control (administered equivalent of distilled water) goats served as subjects. Rectal temperature (measured at 6:00, 13:00 and 18:00 h) and blood samples (taken at 8:00 h) were obtained from all subjects weekly, before, during and after L-glutamine administration. Data obtained were compared using one-way repeated-measures ANOVA, followed by Tukey's post-hoc test. The dry-bulb temperature, relative humidity and temperature-humidity index for the study period ranged between 24.0 and 37.5 °C, 26.0 and 84.0% and 73.0 and 86.3, respectively. L-glutamine administration decreased (P < 0.05) RT, EOF and MDA and increased superoxide dismutase (SOD) activity in experimental group, compared to controls during weeks 1, 2 and 3. Glutathione peroxidase (GPx) and catalase activities were higher (P < 0.05) in the experimental group than in the controls only during week 1 of L-glutamine administration. In conclusion, L-glutamine administration mitigated increases in RT, EOF and serum MDA concentration and enhanced serum SOD, GPx and catalase activities and may be beneficial in heat-stressed goats during the hot-dry season.

Alterations in Intestinal Permeability: The Role of the "Leaky Gut" in Health and Disease

All species, including horses, suffer from alterations that increase intestinal permeability. These alterations, also known as "leaky gut," may lead to severe disease as the normal intestinal barrier becomes compromised and can no longer protect against harmful luminal contents including microbial toxins and pathogens. Leaky gut results from a variety of conditions including physical stressors, decreased blood flow to the intestine, inflammatory disease, and pathogenic infections, among others. Several testing methods exist to diagnose these alterations in both a clinical and research setting. To date, most research has focused on regulation of the host immune response due to the wide variety of factors that can potentially influence the intestinal barrier. This article serves to review the normal intestinal barrier, measurement of barrier permeability, pathogenesis and main causes of altered permeability, and highlight potential alternative therapies of leaky gut in horses while relating what has been studied in other species. Conditions resulting in barrier dysfunction and leaky gut can be a major cause of decreased performance and also death in horses. A better understanding of the intestinal barrier in disease and ways to optimize the function of this barrier is vital to the long-term health and maintenance of these animals.