Rice bran in old horse's nutrition and their influence on condition, blood biochemical parameters, total feces bacteria and methanogen population

This study aimed to verify whether the inclusion of 0.5 kg full-fat rice bran per day in the diet of geriatric horses will improve their condition, increase the population of methanogens in the cecum, and thus affect the biochemical blood parameters. The experiment assumed 2 research periods: 6 healthy, non-working horses over 20 years of age (480 +/- 20 kg of body weight) were fed only hay (+/- 8.86 kg/day/head) in the first period and hay (+/- 8.00 kg/day/head) and rice bran (0.5 kg/day/head) in the second one. Each of these periods lasted 4 months. The Body Condition Scoring (BCS) assessment was performed at the beginning and end of the experiment. Blood and feces samples were collected on the first and last day of each period. After feeding with the addition of rice bran, BCS increased by 1.17 units on a 9-point scale. The experiment showed an increase in the total number of bacteria and methanogens inhabiting the cecum of horses. This can lead to better digestion of carbohydrates, absorption of nutrients, and, consequently, increased body weight. No differences occurred in the hematology and serum biochemistry indices of horses fed a diet including rice bran, except for the amount of serum globulin and the albumin to globulin ratio. Rice bran affected essential serum fatty acid profile (increased PUFA and decreased MUFA) which confirmed the possibility to use diet as a serum fatty acids profile modulator.

Automated summary

This study aimed to investigate the effects of including full-fat rice bran in the diet of geriatric horses on their condition, cecal methanogen population, and blood biochemistry parameters. The results showed that adding rice bran to the diet improved the horses' body condition and increased the number of bacteria and methanogens in their cecum. This led to better carbohydrate digestion, nutrient absorption, and increased body weight. There were no significant changes in the horses' hematological and serum biochemistry indices, except for serum globulin levels and the albumin to globulin ratio. Rice bran also affected the horses' serum fatty acid profile.