Ensiled and Dry Cassava Leaves, and Sweet Potato Vines as a Protein Source in Diets for Growing Vietnamese Large White×Mong Cai Pigs

Abstract

The aim of the present study was to evaluate the effects of replacing 70% of the protein from fish meal by protein from ensiled or dry cassava leaves and sweet potato vines on the performance and carcass characters of growing F1 (Large White×Mong Cai) pigs in Central Vietnam. Twenty-five crossbred pigs (Large White×Mong Cai) with an initial weight of 19.7 kg (SD = 0.84) were allocated randomly to five treatment groups with 5 animals per group (3 males and 2 females). Pigs were kept individually in pens (2.0× 0.8 m) and fed one of five diets over 90 days. The control diet was formulated with fish meal (FM) as the protein source while the other four diets were formulated by replacing 70% of fish meal protein by protein from ensiled cassava leaves (ECL), dry cassava leaves (DCL), dry sweet potato vines (DSPV) or ensiled sweet potato vines (ESPV). Animals were fed their diets at 4% of BW. Results showed that final BW, ADG, DMI and feed conversion ratio (FCR) among the experimental treatments were not significantly different (p>0.05). ECL or DCL and ESPV reduced feed cost per unit gain by 8-17.5% compared to the fish meal diet. There were no significant differences in carcass characters among the diets (p>0.05). Lean meat percentages and protein deposition ranged 41.5-45.8% and 40.2-52.9 g/d, respectively. Using ensiled or dry cassava leaves and sweet potato vine can replace at least 70% of the protein from fish meal (or 35% of total diet CP) without significant effects on performance and carcass traits of growing (20-65 kg) pigs. Including cassava leaves and sweet potato vines could improve feed cost and therefore has economic benefits.

Allzyme SSF supplementation improves the utilization of sweet potato (Ipomoea batatas) vine meal by growing pigs

“…Similar to our findings, Ly et al (2010) also observed no statistical effect of 20% dietary SPLM on DMI, daily weight gain (DWG) and FCR in young pigs. SPVM has a good protein quality, but its poor utilization by monogastric animals is due to the fibre content.…”

“…The lysine and methionine contents of the sweet potato leaf meal used in this study are similar to values (1.08% and 0.54%, respectively) reported in ensiled (An et al 2003), but were higher than the values 0.83% and 0.43% (Ly et al 2010); 0.62 and 0.26% (Farrell et al 2000) in dry sweet potato leaf meal. An et al (2003) and Ly et al (2010) harvested leaves from 60 d-old-sweet potato plants, whereas Farrell et al (2000) pruned the vines at regular intervals from a range of cultivars.…”

“…An et al (2003) and Ly et al (2010) harvested leaves from 60 d-old-sweet potato plants, whereas Farrell et al (2000) pruned the vines at regular intervals from a range of cultivars. Teguia et al (1997) also reported a lower (∼17%) crude fibre in dry sweet potato leaf meal than the value in the present study.…”

“…Sweet potato leaves and vines are moderate to good sources of protein ranging from 26% to 33% (Woolfe 1992;Dung 2001;An et al 2003) with the protein having a good amino acid composition (Ishida et al 2000;NCR 2012) but high in fibre content (Teguia et al 1997;Ly et al 2010). Currently, the leaves and vines from sweet potato harvest have limited use in the South Pacific region.…”

“…Currently, the leaves and vines from sweet potato harvest have limited use in the South Pacific region. There is literature on the feeding of sweet potato leaves/vines in pig diets (Phuc and Lindberg 2001;Ly et al 2010), but exogenous enzyme supplementation of sweet potato vine meal (SPVM)-based diets for growing pigs is not reported. The present study evaluated SPVM with and without Allzyme SSF ® , an enzyme product with seven enzyme activities (amylase, cellulase, phytase, xylanase, betaglucanase, pectinase and protease) for growing pigs.…”