Functional food promotes digestive functions and healthy growth of animals nurtured in confinement

Abstract

In the study, the growth pattern, morphometric and morphological changes in the gastrointestinal tract of growing male and female Sprague-Dawley rats fed crude honey (CH)-supplemented diets as measures of nutrient utilization, digestive functions and healthy growth were investigated. Thirty-five suckling (7-day old male and female) rats were fed CH either as low (10mLkg-1 BW) or high (20mLkg-1 BW) dose daily via stomach tube for 14 days, while the control group was gavaged with distilled water. Rats were kept with their dams to nurse freely between gavages. On weaning, CH was mixed with commercial rat feed as low (20%) or high, 50% (volume/weight, v/w), while 20% (v/w) tap water was added to the control diet. The feed intake of honey-fed male rats and control (infant: 6 – 10g; adult:31 – 38g) was significantly higher (p < 0.05) than their high dose-diet mates (infant: 5 – 8g; adult: 31 – 38g). All the rats were killed at 13 weeks old for gross and microscopic measurements of the abdominal viscera. Grossly, there were no significant differences (p ≥ 0.05) in the relative lengths (%BW) and weight: length ratio (g cm-1 ) of the small and large intestines in both sexes. Crude honey increased the absolute and relative weights of the caecum (1.73 ± 0.05g; 0.38 ± 0.02%BW) and pancreas (2.52 ± 0.11g; 0.55 ± 0.03%BW), with significant influence (p<0.05) in the male rats. In addition, dietary inclusion of CH at low dose enhanced intestinal villi growth in height (84.0 ± 4.0µm) and width (25.2 ± 1.5µm). Dietary supplementation with crude honey also enhanced body weight gain of male rats (495.52 ± 8.98g) and females (242.52 ± 6.87g), improved abdominal organs' functional size: liver (10.92 ± 0.32g; 2.72 ± 0.13%BW); spleen (1.25 ± 0.06g; 0.27 ± 0.02%BW), devoid of pathological changes, as shown by liver histomorphology (1.2 ± 0.3) and normal hepatocellular architecture thereby conferring nutritional and health benefits on animals nurtured in confinement.