Effects of different inorganic:organic zinc ratios or combination of low crude protein diet and feed additives in weaned piglet diets
Received: Aug 23, 2021; Revised: Oct 06, 2021; Accepted: Oct 20, 2021
Published Online: Oct 25, 2021
Thirty-six weaned piglets with an initial body weight of 8.43±0.40kg (28 days of age, LYD) were randomly assigned to 6 treatments for a 2-week feeding trial to determine the effects of different inorganic (IZ), organic zinc (OZ) or combination of low crude protein diet (LP) and feed additives (MFA) on diarrhea score, nutrient digestibility, zinc utilization, blood profiles, organ weight, and fecal microflora in weaned piglet diet. The pigs were individually placed in 45×55×45 cm stainless steel metabolism cages in an environmentally controlled room (30±1℃). The dietary treatments included a negative control (NC), positive control (PC; Zinc Oxide, 1,000 mg/kg), T1 (IZ:OZ, 850:150), T2 (IZ:OZ 700:300), T3 (IZ:OZ, 500:500), and T4 (LP + MFA [0.1% Essential oils + 0.08% protease + 0.02% Xylanase]). The daily feed allowance was adjusted to 2.7 times the maintenance requirement for digestible energy (2.7 × 110 kcal of DE / kg BW<sup>0.75</sup>). This allowance was divided into two equal parts, and the piglets were fed at 08:30 and 17:30 each day. Water was provided <italic>ad libitum</italic> through a drinking nipple. The diarrhea score was significantly decreased (<italic>p</italic> < 0.05) in NC treatment compared with other treatments. The apparent total tract digestibility (ATTD) of dry matter (DM), nitrogen (N), and gross energy (GE) was significantly increased (<italic>p</italic> < 0.05) in the T2 treatment compared with the PC and NC treatments at one week. At two weeks, the ATTD of DM, N, and GE was significantly decreased (<italic>p</italic> < 0.05) in the NC treatment compared with other treatments. The T3 treatment had significantly higher (<italic>p</italic> < 0.05) ATTD and apparent ileal digestibility of zinc than the PC and T1 treatments. The <italic>E.coli</italic> concentration in feces was significantly decreased in the T4 treatment compared with the NC and T2 treatments. The <italic>Lactobacillus</italic> concentration in feces was significantly increased in the T4 and T1 treatment compared with the T2 and T3 treatments. In conclusion, IZ:OZ 500:500 levels could improve nutrient digestibility and zinc utilization in weaned piglets, Moreover, MFA in LP diets could be used as a zinc alternative.