Effect of ensiling treatment on secondary compounds and amino acid profile of tropical forage legumes, and implications for their pig feeding potential

Growth performance of South African Windsnyer pigs to the dietary inclusion of Amarula oil cake

Dietary inclusion of Amarula oil cake (AOC) in pig diets can ease pressure of relying on non-native feed sources and benefit the swine industry. The study was conducted to determine the growth performance of Windsnyer pigs fed increasing levels of AOC. Twenty-five clinically growing male boars with an initial body weight of 19.92 ± 8.74 kg were used in the study that lasted 6 weeks. All pigs were allocated to diets in a completely randomised design. Five experimental diets were formulated to contain 0, 50, 100, 150 and 200 g/kg DM of AOC. Average daily feed intake (ADFI), average daily gain (ADG), feed conversion ratio (FCR), scaled average daily feed intake (SADFI), scaled average daily gain (SADG) and body weight (BW) were calculated weekly. The diet affected ADFI, ADG, FCR and SADG (P < 0.05). Scaled average daily feed intake was not affected by the diet (P > 0.05). There was a significant interaction between AOC inclusion and weeks of feeding on ADFI, ADG and FCR (P < 0.05). Age of pigs decreased FCR quadratically (P < 0.001). A quadratic relationship between ADFI and increasing levels of AOC was observed (P < 0.05). Average daily gain, FCR and SADG decreased linearly with increasing AOC levels (P < 0.05). Using the broken stick analyses, the maximum inclusion of AOC was 102.17 g/kg DM. Amarula oil cake can be incorporated in diets of Windsnyer pigs up to 100 g/kg DM without constraining growth performance.

Browse silage as potential feed for captive wild ungulates in southern Africa: A review

The objective of the review was to assess the potential of indigenous browse trees as sustainable feed supplement in the form of silage for captive wild ungulates. Several attempts to use silage as feed in zoos in temperate regions have been conducted with success. Information on silage from the indigenous browse trees preferred by wild ungulates in southern Africa is scanty. The use of silage from the browse trees is of interest as it has potential to reduce or replace expensive feed sources (pellets, fruits and farm produce) currently offered in southern African zoos, game farms and reserves, especially during the cold-dry season. Considerable leaf biomass from the indigenous browse trees can be produced for silage making. High nutrient content and minerals from indigenous browsable trees are highly recognised. Indigenous browse trees have low water-soluble carbohydrates (WSC) that render them undesirable for fermentation. Techniques such as wilting browse leaves, mixing cereal crops with browse leaves, and use of additives such as urea and enzymes have been studied extensively to increase WSC of silage from the indigenous browse trees. Anti-nutritional factors from the indigenous browse preferred by the wild ungulates have also been studied extensively. Indigenous browse silages are a potential feed resource for the captive wild ungulates. If the browse trees are used to make silage, they are likely to improve performance of wild ungulates in captivity, especially during the cold-dry season when browse is scarce. Research is needed to assess the feasibility of sustainable production and the effective use of silage from indigenous browse trees in southern Africa. Improving intake and nutrient utilisation and reducing the concentrations of anti-nutritional compounds in silage from the indigenous browse trees of southern Africa should be the focus for animal nutrition research that need further investigation.

Ensiling a dry bakery by-product: effect of hydration using acid whey or water associated or not at urea

SUMMARY The objective of this study was to investigate the characteristics of silages prepared with a dry bakery by-product hydrated with acid whey or water associated or not at urea. The trial was a 3 (hydration at three moisture levels: 250, 300, and 350 mL kg−1 of by-product) × 3 (three application rates of urea: 0, 5, and 10 g kg−1 of by-product) × 2 (liquid used at hydration: acid whey or water) factorial arrangement. Mini-silos were used as experimental silos and remained closed for 30 days. Overall, silages hydrated with acid whey had higher (P<0.01) production of lactic (19.6 vs. 18.5 g kg−1 of dry matter [DM]), acetic (2.5 vs. 1.8 g kg−1 of DM) and propionic acid (8.0 vs. 5.4 g kg−1 of DM), and lower (P<0.05) fungi counts (5.35 and 5.01 cfu g−1 of fresh silage) compared to silages hydrated with water. Increased hydration led to the higher production of total acids (P<0.01), decreasing silage pH; but increased hydration reduced DM recovery (P<0.01). Silages hydrated with water and acid whey at 250 mL kg−1 and combined at 5 and 10 g kg−1 of urea exhibited higher DM recovery (P<0.05). Silages of a dry bakery by-product hydrated with acid whey had a better fermentation pattern and could represent a practical strategy to avoid discarding both by-products into environment.

Nutritive value of three tropical forage legumes and their influence on growth performance, carcass traits and organ weights of pigs

The effects of tropical forage legumes on feed intake, growth performance and carcass traits were investigated in 16 groups of two Large White × Duroc pigs. The diets consisted of a commercial corn-soybean meal diet as the basal diet and three forage-supplemented diets. Four groups of control pigs received daily 4 % of body weight of the basal diet, and 12 groups of experimental pigs were fed the basal diet at 3.2 % of body weight completed with fresh leaves of one of the three forage legumes (Psophocarpus scandens, Stylosanthes guianensis and Vigna unguiculata) ad libitum. The study lasted 90 days. The in vitro digestion and fermentation of the forage legumes were also determined. The in vitro digestible energy content of the legumes was between 0.72 and 0.77 that of the basal diet (14.4 MJ/kg dry matter (DM)). V . unguiculata was the most digestible forage legume expected for crude protein digestibility. Feeding forage legumes lowered the dry matter intake by 4.5 to 9.6 % (P < 0.05), final body weight (P = 0.013), slaughter weight, average daily gain and hot carcass weight (P < 0.05) without affecting the feed conversion ratio (FCR), dressing percentage and back fat thickness. In conclusion, using forage to feed pig could be interesting in pig smallholder production with limited access to concentrate, as FCR was not significantly affected.

Feed intake and growth performance of growing pigs fed on Acacia tortilis leaf meal treated with polyethylene glycol

The objective of the study was to determine the response in feed intake and performance of pigs fed on incremental levels of polyethylene glycol (PEG). Forty-eighty male F1 hybrid pigs were randomly allotted to six diets containing 0, 5, 10, 15, 20, and 25 g/kg of PEG, respectively. Acacia tortilis leaf meal was included at a rate of 150 g/kg. Each diet was offered ad libitum to eight pigs in individual pens. Average daily feed intake (ADFI), scaled feed intake (SFI), average daily gain (ADG), and gain to feed ratio (G:F) were determined weekly. The ADG showed a linear response to PEG (p < 0.01). The linear regression equation was y = 0.0061x + 0.6052 (R(2) = 0.64). There was a quadratic response to PEG on ADFI, and SFI (p < 0.01) and G:F (p > 0.05). The regression equations and R(2) values were as follows: ADFI y = 0.0008x(2) - 00086x + 1.2339 (R(2) = 0.96), SFI y = 0.0147x(2) - 0.2349x + 40.096 (R(2) = 0.95), and G:F ratio y = 0.0002x(2) - 0.0017x + 0.5168 (R(2) = 0.56). The ADFI, SFI, and ADG increased as weeks of feeding progressed (p < 0.01), but the G:F ratio decreased as weeks increased. It can be concluded that the relationship between PEG inclusion and performance of growing pigs fed on A. tortilis is exponential, rather than linear. The economic benefit of using PEG depend on cost of labor, availability of Acacia, costs of harvesting together with processing, and acceptability of the pork.

Forage plants as an alternative feed resource for sustainable pig production in the tropics: a review

Globally, pressure on concentrate feed resources is increasing, especially in the tropics where many countries are net importers of food. Forage plants are a possible alternative, but their use as feed ingredients for pigs raises several issues related to their higher fibre and plant secondary metabolites contents as well as their lower nutritive value. In this paper, the nutritive value of several forage species and the parameters that influence this nutritive value in relationship to the plant family, the physiological stage, the plant part and the preservation method (fresh, hay and silage) are reviewed. The influence of the breed and the physiological status of the animal on animal voluntary intake of fibre-rich ingredients, digestibility as related to gastrointestinal volume and transit time and growth performances are also discussed. The final section highlights the advantages and drawbacks of forage plants in pig diets and stresses the need for proper economic evaluation to conclude on the benefits of the use of forage plants in pig feed.