Weaning stress is the most common issue in weanling pigs, and increases diarrhea and mortality. Various wavelengths of light irradiation affect the body owing to the association with biophotons. Biophotons are very weak photons in the visible light range generated during metabolic and chemical reactions in vivo. Immune mechanisms are activated by increasing signal transmission between cells through biophoton emission. This study evaluated the influence of ultra-weak light (LED) on growth performance, antioxidant status, and stress of weaned piglets. A total of 120 weaned pigs with an average initial body weight of 7.04±0.01 kg (age: 21 d) were allotted to two treatments (Control and LED) with 10 replicates. Diets prepared in pellet form were administered to the pigs in three phases including Phase 1 (0–14 d), Phase 2 (15–28 d), and Phase 3 (29–42 d). At the end of the study, the average daily gain (8.96%, p<0.05) and feed efficiency (6.56%, p<0.05) of pigs was significantly increased at phase 3 in the LED treatment. Low concentration of malondialdehyde (12.58%, p<0.05) and high concentrations of glutathione reductase (7.41%, p<0.01) and total antioxidant capacity (5.48%, p<0.05) were observed in the LED treatment at Day 42. The concentration of hair cortisol was also decreased (24.05%, p<0.05) in the LED treatment at Day 42. In conclusion, the use of LED for weanling pigs is recommended to improve growth performance by modulating antioxidant capacity and cortisol level in hair.

We aimed to investigate the effect of environmental enrichment via toys on the behaviour and performance of weanling pigs. A total of 300 pigs (LYD) were housed in different pens with ten pigs per replicate and ten pigs per head divided into 3 groups. Group 1 was called “CON” and received no toys, group 2 was TOY-2, and pigs in this group had access to toys in the first 2 weeks, and lastly, pigs in TOY-4 were given toys in the fourth week. The pigs had access to feed and water ad-libitum. The individual pig behaviours in each group was recorded on days 14 and 28 (d 14 and 28) with a video camera for accuracy. The results showed higher (p<0.05) overall ADG in TOY-4 compared with CON, while the overall ADFI was higher (p<0.05) in TOY-supplemented groups compared to CON. Diarrhea incidence and fecal score were lower on D 14 in TOY-supplemented groups compared with CON. Behavioural features such as ear biting and fighting were lower (p<0.05) in TOY-supplemented groups compared with CON on D 14. Tail biting was lower (p<0.05) in TOY-2 compared with CON at D 14. Conversely, at D 28, tail biting was lower (p<0.05) in TOY-4 compared with CON. The ADG improved due to the toy supplied to reduce undesirable social behaviours. We concluded that the environmental enrichment of pens with toys can help to improve the welfare in weaning pigs, leading to a greater survivability and more production thereby improving farmer incomes.

This study investigated various levels of sodium nitrite and probiotics (SNPro) combination as an alternative to zinc oxide on the growth performance, immune response, intestinal microflora, and morphology of weaned pigs. One hundred and ninety-two weaned pigs (Landrace×Yorkshire×Duroc) with an average body weight of 6.51±0.15 kg were randomly assigned to four treatments(n=6) on the basis of their initial body weight. Experimental period was divided into phase 1 and 2 (each 14 days). The dietary treatments were: 1) Basal diet (control), 2) SNPro1 (control+0.01% SNPro), 3) SNPro2 (control+0.02% SNPro), 4) SNPro3 (control+0.03% SNPro). The average daily gain when SNPro was added to the diet was 288, 309, 319, 324 g in phase 1, 355, 387, 410, 407 g in phase 2 and 321, 348, 364, 366 g in the overall. The concentration of interleukin-8 and interleukin-10 in serum when SNPro was added to the diet were 15, 13.5, 13, 12.8 ng/ml and 165, 162, 155, 145 ng/ml (p<0.05) but toll-like receptor 4 and immunoglobulin G levels in serum were no significantly different. The colonization of Escherichia coli in the ileum and Salmonella spp. in the caecum were significantly decreased as SNPro level increased (p<0.05). However, the population of Lactobacillus spp. did not differ among the groups. Although villus height and villus height to crypt depth ratio were not significantly affected by the treatments, crypt depth in the jejunum was 599, 586, 615, 599 ㎛ as SNPro level increased (p<0.05). In conclusion, SNPro had beneficial effects on growth performance, immune response, intestinal microflora and morphology weaned pigs. Therefore, SNPro not only can be considered as an alternative for the pharmacological level of zinc oxide in weaning pigs but also ideal dietary SNPro level was 0.02%.

This study was conducted to determine the effects of dietary protein level and supplementation of protease on growth performance, nutrient digestibility, gut microflora, intestinal morphology and fecal noxious gas emission in weanling pigs. A total of 240 weaned pigs (Landrace×Yorkshire×Duroc, 5.82±0.3 kg) were used during 4 weeks in 2 phases (days 0-14, phase 1; and days 15-28, phase 2) feeding program based on age and initial body weight. Pigs were allocated to 2×2 factorial arrangement, including 2 protein levels (HP, high protein; LP, low protein) and 2 protease levels (with or without protease). The average daily gain in the LP treatment (357 g/d) was increased rather than the HP treatment (339 g/d). A greater avarage daily gain was observed in dietary suppiemented protease treatment (358 vs 339 g/d). Average feed intake was greater in the LP treatment (544 g/d) rather than the HP treatment (530 g/d). A greater average daily feed intake was observed in dietary supplemented protease treatment (552 vs 523 g/d). Dry matter and crude protein digestibility were increased in dietary supplemented protease treatment (82.62% and 76.08%, respectively) rather than non-supplemented treatment (81.74% and 75.13%, respectively). Ileal Lactobacillus spp. count increased in dietary supplemented protease treatment (7.42 vs 7.32 log10CFU/g). Emission of H2S was decreased in the LP treatment (4.41 ppm) rather than HP treatment (4.78 ppm). Emission of NH3 was decreased in dietary supplemented protease treatment (10.43 ppm vs 11.76 ppm). In conclusion, the decrease of dietary protein level and supplementation of protease had beneficial effects on growth performance, nutrient digestibility, gut microflora, and noxious gas emission in weanling pigs.

The objective of this experiment was to determine the effect of supplementation of hot melt extrusion (HME) processed Zn sulfate on growth performance, nutrients digestibility, small intestinal morphology and excretion of Zn in weanling pigs. A total of 200 piglets of mixed sex randomly allotted to four treatments on the basis of initial BW (7.15±0.81 kg). There were five replicates in each treatment with 10 pigs per replicate. The experimental treatments consisted of: 1) basal diet containing ZnSO4; 2) basal diet containing Zn-Methionine (ZnMet); 3) basal diet containing low level of nano-Zn as HME (ZnHME50); 4) basal diet containing medium level of nano-Zn as HME ZnSO4 (Zn-HME75). The average daily gain was improved by the ZnMet and ZnHME75 compared with the pigs fed ZnSO4 supplemented diets (p=0.009). Moreover, ZnHME75 and ZnMet affected on the ATTD of CP during phase 2 (p=0.014). The villus height (VH) was affected by increasing when pigs fed diets supplemented the ZnHME75 (P=0.044). The pigs fed diets supplemented ZnHME50 had significantly the lowest (p=0.037) Zn content in liver compared with other treatments. The Zn content in the feces was significantly higher (p<0.001) in ZnSO4 and ZnMet compared with ZnHME50 or ZnHME75. In conclusion, it could be concluded that dietary Zn can be reduced by 25% with ZnHME without any detrimental effect on performance of weanling pigs.