Abstract
Growth retardation of calves is defined as a symptom of impaired growth and development, probably due to growth hormone disorder as well as natural and environmental factors in livestock. The growth-promoting effects of probiotics were determined in 50 growth-retarded growth calves. They were supplied with Bacillus amyloliquefaciens C-1 (Ba, 4 × 1010CFU/d, n = 16), B. subtilis (Bs, 4 × 1010CFU/d, n = 18), and negative control (NC, n = 16) for 30 days. Pre- and post-intervention, the growth performance (weight gain rate, feed intake and feed conversion rate) was analyzed, the serum GH, IGH-1 and immunoglobulin levels were assayed, and the fecal microbiota was detected. Calves in Ba and Bs groups demonstrated increased body weight gain, feed intake and GH/IGF-1 levels, as well as a more efficient feed conversion rate, compared with NC group (P < 0.05). Additionally, the abundances of bacteria contributing to the production of energy and SCFAs (short chain fatty acids), including Proteobacteria, Rhodospirillaceae, Campylobacterales, and Butyricimonas were increased compared with NC group (P < 0.05, FDR < 0.1); and the suspected pathogens, which included Anaeroplasma and Acholeplasma were decreased (P < 0.05, FDR < 0.1) in both the Bs and Ba groups. Akkermansia, which is involved in the intestinal mucosal immune response, was increased in Bs group after intervention (P < 0.05, FDR < 0.1), but exhibited no obvious difference in Ba group. The increased bacterial genera in Ba group were Sphaerochaeta and Treponema (P < 0.05, FDR < 0.1). These results indicate that the probiotics B. amyloliquefaciens and B. subtilis exhibited similar therapeutic potential in terms of growth performance by regulating hormones, and improving the intestinal and rumen development in growth-retarded animals.
Highlights
Hybrid Qinchuan cattle and Japanese black cattle are intensively cultivated to supply the beef market in northwest China (Jiao et al, 2017)
The initial body weight among NG, Bs, and Ba group showed no obvious difference (P = 0.06), the average age had difference (P = 0.04), take the consideration of body weight and age together using SPSS, there had no obvious difference among three groups (P = 0.06)
Previous studies revealed that daily oral supplementation with Lactobacillus fermentum I5007 for neonatal piglets reduced the incidence of diarrhea, improved growth performance, favored intestinal development and altered the intestinal microbiota (Liu et al, 2014)
Summary
Hybrid Qinchuan cattle and Japanese black cattle are intensively cultivated to supply the beef market in northwest China (Jiao et al, 2017). The refractory growth retardation occurs in beef cattle with normal birth weights, and causes great economic loss. Young animals with growth retardation are associated with extremely low feed conversion efficiency, high morbidity and mortality, which lead to increased farming costs and reduced production profit (Hu et al, 2016). A variety of studies have been performed with growth-retarded calves and have implicated somatotropic axis hormone secretion deficiency (Hu et al, 2016), as well as environmental factors, including food deprivation, malnutrition and disease (Fawzi et al, 1997; Hoffman, 1997; Mourits et al, 1997). Direct injection of GHRP1 improves endogenous growth retardation in yaks (Hu et al, 2016). Sugar supplementation was proved to stimulate the growth performance in growth-retarded Japanese black calves (Sato et al, 2010). Some of the results have been rather difficult to apply directly to farm conditions, and do not completely reverse growth retardation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
