Increasing smallholder pig farmers' adaptive capacity: Low-cost balanced diets for East African pigs using livestock and plant co-products

By acquiring livestock poor farmers can ascend out of poverty. Pigs require minimal inputs and raising them is often within disadvantaged members of society’s means. In East Africa, 2.2 million pigs are raised by resource-poor, subsistence farmers most with under 2 hectares of cropland. They typically raise 1–4 pigs to pay for school, medical costs, food, and seeds, but pig productivity is low. Lack of feed, seasonal feed shortages and unbalanced diets contribute to slow growth, resulting in compromised earnings from pig-raising. We estimated East African pig feedstuff nutrient composition through nutrient analysis and from literature. Seasonal availability was identified by local experts. Performance results from local-breed pig feeding trials were used to adjust the NRC (2012) nutrient requirement model for growing-finishing pigs. Local pigs’ nutrient requirements under typical management conditions (intestinal parasites present and free-ranging) were estimated. A least-cost diet formulation programme was used to generate diets minimising cost and human/pig competition for food, maximising agricultural co-products and forages use, considering seasonal availability, and satisfying minimal requirements for digestible energy 2960 kcal per kg of dry matter [DM]), calcium, standardised total tract digestible phosphorous, standardised ileal digestible crude protein and lysine (0.28, 0.13, 8.5, and 0.58% of DM respectively) Feedstuffs availability differed between November-February; June-August; and March-May plus September-October. Estimated growth performance potential of local pigs is less when free-ranging, or intestinal parasite infected, than when restrained and non-infected (80; 217; and 259 g per day respectively) A typical least-cost diet for June-August (all as % of DM) is: maize flour 20.6; cassava leaf 20.0; sweet potato vine 19.2; ripe avocado 15.0; Bidens pilosa 7.9; limestone 7.7; molasses 5.0; cattle blood 3.9; Amaranthus spinosus 0.3; table salt 0.24; premix 0.10. Sun-dried fish (Rastrineobola argentea) and grist mill waste are available all year as substitutes for seasonably available ingredients e.g avocado and sweet potato vine. Use of such diets will enable continuous pig feeding during all seasons, thereby increasing farmer resilience. Their use will improve pig performance resulting in increased farmer income, enabling poverty alleviation, improved food security, human health and nutrition, and investment in other livelihood ventures to further increase resilience

Influence of dietary methionine to methionine plus cysteine ratios on nitrogen retention in gilts fed purified diets between 40 and 80 kg live body weight

The relationship between the ratio of available methionine (MET) to methionine plus cysteine (TSAA) intake and wholebody protein deposition (PD) was established using the nitrogen (N) balance technique in gilts between 40 and 80 kg live body weight (BW), according to a repeated 5 × 5 Latin square design. Pigs were fed casein- and cornstarch-based diets that supplied equal moles of TSAA supporting a PD of approximately 80% of the gilts’ PD potential. On a weight basis, the target ratios of MET to TSAA were 42, 47, 52, 57 and 67% for the five experimental diets, respectively. This calculated to 37, 42, 47, 52 and 62.5% on a molar basis. Total N excretion (urine plus feces) was reduced (linear; P 0.05) when the MET to TSAA ratio was further increased. A number of statistical models were fitted to the data to establish the best fit of the model parameters. The greatest proportion of the variation (R2 = 0.990) was explained with an asymptotic model; based on this model the optimum available MET to TSAA ratio (supporting 90% of the asymptotic value for PD) was 55% on a weight basis or 50.5% on a molar basis. The results indicate that the minimum contribution of available MET to TSAA requirements of growing pigs is higher than the value currently suggested by the National Research Council (46 to 48% on a weight basis)

Body weight gain and nutrient utilization in starter pigs that are liquid-fed high-moisture corn-based diets supplemented with phytase

A total of 384 starter pigs were used to examine the application of exogenous phytase in high-moisture corn (HMC)-based liquid diets. Pigs were randomly assigned to 24pens in six blocks. Pens were randomly assigned one of four HMC-based diets formulated to vary in total phosphorus (P) content (Low, Medium and High), with phytase added to only the Low P diet (Phy). Body weight gain and feed intake were monitored until body weight exceeded 20 kg. Apparent total tract digestibility of crude protein and P were measured on day 21 (Phase II) and day 42 (Phase III). At the end of the trial, two pigs from each pen were sacrificed for analysis of carcass composition and evaluation of metacarpals. Pigs fed the Phy treatment had increased digestibility of crude protein (P0.05). In conclusion, performance of starter pigs fed liquid HMC-based diets was maintained at dietary P levels below established requirements, but addition of phytase improved bone strength and mineralization. This study provides evidence for the effectiveness of phytase, and that P requirement for maximum rate of weight gain in pigs is not sufficient for maximum skeletal development