Objective: The efficacy of Salmonella typhimurium-specific bacteriophage STP-1 on S. typhimurium infection in weaning piglets was evaluated in this study. Material and Methods: Twenty-eight weaning piglets were randomly allocated to four groups (Group A: non-challenged/basal; Group B: non-challenged/+phage; Group C: challenged/basal; Group D: challenged/+phage) according to S. typhimurium infection or bacteriophage administration. The total experimental period (14 days) was subdivided in to non-challenged periods (phase I; day 17) and challenged periods (phase II; day 714) based on the challenging date (day 7). Each group was fed with basal feed or feed supplemented with bacteriophage STP-1 [1.0 × 109 plaque-forming unit (PFU)/kg] during the whole period (day 114). Body weights (BW) were measured to evaluate growth performance. Clinical symptoms (rectal temperatures and fecal consistency) induced by S. typhimurium were regularly checked. Bacteria colonization levels in feces and intestinal tissue samples were measured using real-time polymerase chain reaction (PCR). After necropsy, small intestine samples (jejunum) were collected. Villus height and crypt depth (CD) were measured through histological examination with H&E staining. Results: The supplementation of bacteriophage significantly reduced bacterial colonization and intestine damage in the piglets infected with S. typhimurium. In the antigen concentrations of the feces and jejunum, Group C showed 5.8 ± 0.6, 5.7 ± 0.6, and 1.2 ± 2.0 log colony-forming unit (CFU)/ml on 1, 3, and 7 days post-inoculation (DPI) and 2.8 ± 1.3 log CFU/ml, whereas Group D showed 3.5 ± 1.7, 2.2 ± 2.1, and 0.3 ± 0.9 log CFU/ml on 1, 3, and 7 DPI and 5.1 ± 0.9 log CFU/ml. In the villous height, Groups C and D showed 266.3 ± 24.1 and 324.6 ± 18.0 μm, respectively. In the goblet cell density of villi and crypts, Group C showed 10.0 ± 1.8 and 16.0 ± 3.7, while Group D showed 15.0 ± 4.8 and 21.1 ± 5.4. Also, the supplementation of bacteriophage significantly improved the growth performance in the infected piglets. The average daily gains of Groups C and D were 91 ± 24 and 143 ± 23, respectively, during the period after inoculation with S. typhimurium. Conclusion: The dietary supplementation of the phage was effective for alleviating S. typhimurium infection in post-weaning piglets. [J Adv Vet Anim Res 2021; 8(3.000): 440-447]

In an effort to increase profitability, sows have been systematically selected for higher litter sizes. That may have led to an increase in pre-weaning mortality. To improve new-born survival, sows should be taken cared of stringently, especially the housing system and the sows’ nutritional management in both the gestation and the farrowing houses. Additionally, the sows’ reluctance to drink water after giving birth and the sow induction at the farrowing house can negatively affect both the new-born piglets and farrowed sows. Also inevitable is the extended farrowing duration associated with exceptionally large litters. Therefore, assistance during farrowing time is essential. The importance of colostrum intake should also be emphasized and that piglets should be fostered, if needed, to ensure that they have teats to suckle on. Moreover, milk replacer and creep feeding are also helpful options to aid in piglet’s nutrition requirement. Last but not least, farm caretakers who look after the piglets should be well-trained. This study looked into some strategies to improve piglet survivability by pointing out details in the routine activities at the farm.