| Abstract: | This study investigates the use of refined potato protein (RPP) obtained from the potato (Solanum tuberosum) tubers of “Gogu valley” for their antimicrobial properties and its effects on growth performance, apparent nutrient digestibility and microbial populations in feces and large intestine of weanling pigs. Pigs (n = 280; Landrace × Yorkshire × Duroc; average initial body weight of 5.96 ± 0.66 kg; 23 ± 3 d of age) were allotted on the basis of their body weight and sex to five dietary treatments (each treatment comprised of 4 replicate pens with 14 pigs in each) in a randomized complete block design. The dietary treatments were: PC (positive control; basal diet + 150 ppm apramycin sulfate and 10 ppm colistin sulfate), and RPP (basal diet added with 0, 200, 400 and 600 ppm RPP). The RPP showed in vitro antimicrobial activity and at the concentration of 150 ppm inhibited the growth of tested microbes (Staphylococcus aureus, Salmonella choleraesuis, Salmonella gallinarum and Escherichia coli). Pigs fed with antibiotic diet showed better growth performance and had lower populations of total bacteria, coliforms and Staphylococcus spp. in the feces and large intestine when compared with pigs fed RPP diets. Increasing the levels of RPP in diets linearly improved performance and reduced the populations of total bacteria, coliforms and Staphylococcus spp. in feces and contents of colon and rectum. The apparent fecal digestibility of DM, CP and apparent ileal digestibility of amino acids did not differ among pigs fed antibiotic and RPP diets. These results suggest that antibiotics were more effective in improving the performance of pigs, while feeding of RPP also improved the performance and reduced the harmful microbes being more effective at higher levels. Thus at higher levels RPP obtained from the potato tubers of Gogu valley can be a potential replacement of antibiotics in the feed of weanling pigs. |
