Abstract
In order to evaluate the nutritional levels of feedstuffs suitable for fattening of Kagoshima Berkshire swine, simple feeding was conducted in the present study with the swine since their live body weight of 30kg in cage-type pigpens.
In the feeding test, self-compounded feedstuffs with varying TDN levels of 63, 68, 73, and 76.5 and with an almost fixed level of proteins (DCP 11.5-12.0) were kept fed up until their body weights of 50-90kg so as to comparatively evaluate their growths, utility of feedstuffs, results of performances with carcass evaluation, economy, and meat quality (PSE pork). The results were as summarized hereunder.
1. With the feed of a TDN of 63, the growths of the swine were slower and the back fat layer was thinner. The results of grading of their carcass were also lower, but the meat quality (firmness and exudative) tended to be better.
2. With the feed of a TDN of 76.5, the results of the growth (weight gain and feed conversion rate) were better than the counterparts of the feedstuffs with TDNs of 63, 68 and 73, but the back fat layer in this group was thicker and the result of rating of their carcass of undergrade was 15.4%, which was higher than that of the group with a feed of TDN of 73 (7.1%).
3. With the feed of a TDN of 73, a case of PSE pork of a light degree was noted, which was, however, of such an extremely low ratio of 0.02%. It was, however, suggested that there may be incidents of PSE pork if the rate of growth is accelerated in Kagoshima Berkshire swine.
4. With the feed of a TDN of 68, the mean daily weight gain (50-90kg) was approx. 545g and the feed conversion rate was approx. 4.1, which was the standard in Kagoshima Berkshire. The results of grading of carcass were the best in this group and the swine in this group demonstrated superior economy and meat quality.
5. From the results of these findings, it can be assumed that the levels of nutrition for the feedstuffs suitable for fattening of Kagoshima Berkshire swine would be a TDN of 68-73 and a DCP of approx. 11.5.
