Korean Journal of Agricultural Science (농업과학연구)

Institute of Agricultural Science, CNU (충남대학교 농업과학연구소)
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Determination of dietary Ca and P levels and their equivalence values of phytase and vitamin D3 for improved growth performance in weanling pigs

  • Ogola, Oketch Elijah (Department of Animal Science and Biotechnology, Chungnam National University) ;
  • Choi, Jun Seung (Department of Animal Science and Biotechnology, Chungnam National University) ;
  • Hong, Jun Seon (Department of Animal Science and Biotechnology, Chungnam National University) ;
  • Kim, Yu Bin (Department of Animal Science and Biotechnology, Chungnam National University) ;
  • Nawarathne, Shan Randima (Department of Animal Science and Biotechnology, Chungnam National University) ;
  • Yu, Myunghwan (Department of Animal Science and Biotechnology, Chungnam National University) ;
  • Heo, Jung Min (Department of Animal Science and Biotechnology, Chungnam National University)
  • Received : 2021.05.14
  • Accepted : 2021.06.17
  • Published : 2021.09.01
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Abstract

In Experiment 1, the impact of using diets sufficient in P on the performance of weaned piglet growth with or without a super dose of phytase was investigated. One hundred and twelve piglets were randomized into four treatments with 7 replicates (4 piglets·cage-1). Bodyweight (BW), daily gain (ADG), daily intake (ADFI) and feed conversion ratios (FCR) were measured over three weeks. Treatments included a positive control (PC) with a Ca : P ratio of 0.80 : 0.50%. and the negative control (NC) had a Ca : P ratio of 0.60 : 0.50%. The PC plus phytase was denoted as PC+, and the NC with the phytase diet was designated as NC+. The PC diet was formulated to meet or exceed the NRC (2012) standards for pigs weighing 7 - 25 kgs. Better results were obtained with the PC diet (p > 0.1) compared to the NC diet. The super dose of phytase in the PC+ diet significantly improved the overall FCR (p < 0.1). For Experiment 2, the impact of different calcium (Ca)/phosphorous (P) ratios with or without supplementation of vitamin D3 was determined. Ninety-six piglets were randomized into four treatments with 6 replicates (4 piglets·cage-1). The PC, NC1 and NC2 diets had ratios of 0.80 : 0.50, 0.80 : 0.45, and 0.60 : 0.45%, respectively. The fourth diet (PCV) was the PC diet fortified with vitamin D3. Improved results were observed with the PC diet (p > 0.1) compared to the NC diets. Supplementing dietary 25-OH-D3 in the PCV diet led to numerically higher ADG and ADFI scores with lower FCR values at the early nursery stage (p = 0.0044), but the vitamin supplement did not significantly influence the growth.

Keywords

Acknowledgement

The authors acknowledge the support provided by Dodram Pig Farmer's Service CO., Ltd., South Korea.

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