In order to determine the relationship between boron and development of the spleen, especially in the promoting biological effects, we examined the effects of different levels of boron on weight, organ index, microstructure, and antioxidative activities of the spleen in rats. Sprague-Dawley (SD) rats were selected and treated with different concentrations of boron, and then, the organs were resected and weighed. One half of the tissue was fixed and embedded in paraffin to observe tissue structure changes. The other half of the tissue was homogenated for determining the antioxidant activities. The results showed that 40 mg/L of boron could increase weight, organ indexes, and antioxidant capacity of spleens and improve the spleen tissue structure, while the boron concentration above 80 mg/L could decrease weight, organ indexes, and antioxidant capacity of spleens and damage the spleen tissue structure. The higher the concentration, the more serious the damage was. Especially at the concentration of 640 mg/L, it could significantly inhibit the development of the spleen and even exhibit toxic effect. Hence, low boron concentration played a protective role in the development of the spleen, while high boron concentration could damage the organs and even produce toxic effect.

This paper aims to evaluate the effects of probiotics (Bacillus subtilis, Bacillus licheniformis, and Bacillus natto) on muscle development and meat quality of broilers. In this study, 480 broilers (1 day old) were randomly divided into 4 groups. Group A was fed with a basal diet. The basal diets of Group B, Group C, and Group D were respectively supplemented with 50 mg/kg chlortetracycline, 200 mg/kg probiotics, and 400 mg/kg probiotics. On day 21 and day 42, in each group, 18 randomly selected broilers were tested to determine muscle performances. On day 21, compared with Group A, Group C and Group D showed no significant difference in muscle weight, muscle fiber diameter, meat color, drip loss, shear loss, or cooking loss (P > 0.05). On day 42, compared with Group A, Group C and Group D showed significant increases in muscle weight and muscle fiber diameter and significant decreases in b* value, drip loss, cooking loss, and shear force (P < 0.05). Compared with Group A and Group B, Group C and Group D showed obviously improved muscle microstructure. In conclusion, diets supplemented with 200 or 400 mg/kg probiotics could promote muscular development and meat quality of broilers in the late stage of growth.