229 Effect of Two Sources of Zinc on Growth Performance and Gut Health of Piglets with a Low or Normal Birth Weight

Abstract

Abstract Zinc (Zn) is an essential trace element for piglets. The study aimed to compare effects of two Zn sources on piglets divided into two body weight (BW) categories. At birth, piglets were weighed and divided into low BW (LBW < 1 kg) or normal BW (NBW > 1 kg). At weaning (25 days of age, d 0), 64 piglets were divided into 4 groups (8 replicates of 2 piglets/group) as follows: 1) LBW piglets fed a standard diet plus 120 ppm of Zn from ZnSO4, 2) NBW piglets fed a standard diet plus 120 ppm of Zn from ZnSO4 (CO), 3) LBW piglets fed standard diet plus 120 ppm of Zn from a potentiated Zn source (HiZox, HZ), and 4) NBW piglets fed a standard diet plus 120 ppm of Zn from a potentiated Zn source HZ. Growth performance was measured at d 0, d 9, d 14, and d 21. The fecal index was recorded daily. On d 9 and d 21, one piglet per replicate was slaughtered. Blood and gut tissue were collected to evaluate the immune and inflammatory status of the piglets. The groups were arranged using a 2 x 2 factorial design, considering the class of birth BW (LBW and NBW) and the diet (CO and HZ). For the diarrhea index, a generalized linear mixed model fitting a Poisson distribution was used. Other variables were analyzed with a linear mixed model, in which the diet, class of BW and their interaction were included as fixed factors and litter of origin was included as a random factor. Piglets from the NBW group had consistently greater BW throughout the study (P < 0.01) than LBW piglets. The treatment HZ tended to improve BW gain from d 0 to d 9 and from d 9 to d 14 (P < 0.10), and significantly influenced the G:F ratio (P < 0.05). The fecal index was decreased by HZ from d 0 to d 14, and from d 0 to d 21 (P < 0.01), particularly for LWB piglets (P-interaction < 0.01). Haptoglobin and reactive oxygen metabolites decreased from d 9 to d 21 (P < 0.01) in serum. Expression of the NFKB-2 gene was less in NBW piglets than in LBW piglets and in HZ groups. In conclusion, potentiated Zn positively influenced the growth performance of LBW and NBW piglets.