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The study evaluated the effects of feeding incremental levels of sericea lespedeza (SL; 0, 62.5, 125, 187.5 and 250 g/kg diet) substituted for lucerne on meat production, quality, and oxidative shelf-life of feedlot lambs infected or non-infected with Haemonchus contortus. There were no diet × infection status, and diet × retail display period effects for all the tested parameters (P 0.05). Relative to the other diets, the 250 g/kg SL diet decreased (P ≤ 0.05) lamb growth performance and carcass yield. The SL diets experienced less (P ≤ 0.05) meat lipid oxidation than the control diet. Worm infection reduced (P ≤ 0.05) carcass yield and income-over-feed-costs without affecting meat quality (P 0.05). Feeding SL had no effects on meat physicochemical, fatty acid, colour, and protein shelf-life profiles (P 0.05). Overall, substituting lucerne with SL up to 187.5 g/kg in lamb feedlot diets has no effects on meat production and quality but enhances lipid stability regardless of infection.

The Department of Science and Technology-National Research Foundation (DST-NRF) Centre of Excellence (CoE) in Food Security (grant number: 140102).

Water scarcity is among key the challenges facing sheep production in the arid and semiarid areas, and is predicted to worsen in future. Despite sheep in dry areas being capable of surviving relatively long periods with little water, deficiency of this essential nutrient produces lightweight carcasses and dark, dry and less tender meat. Responses to impacts of water scarcity have often been reactive rather than proactive, focusing on crisis rather than risk management. To effectively minimise the impact of water scarcity on dryland sheep meat production and quality, water-scarce countries should adopt a new paradigm for water management aimed at risk reduction. This entails identification and adoption of a menu of local recovery and resilience interventions spanning the spectrum from management of water, feed and animals to human resources capacitation. Most of the existing recovery and resilience strategies in water-scarce sheep producing countries have, however, not been widely adopted due to lack of evidence, resources, and adaptive capacity. The current review, therefore, discusses the impacts of water scarcity on sheep meat production and quality, and identifies a portfolio of local recovery and resilience strategies for adoption by dryland countries.

Beef production in the smallholder sector of South Africa is constrained by low feed quantity and quality, particularly protein during the dry season. The objective of the study was to evaluate the effect of replacing Glycine max in a complete finisher beef cattle diet with either Acacia mearnsii leaf meal or Medicago sativa hay on growth performance, carcass traits and meat quality of steers. Thirty-six, 12-months old non-descript crossbred steers (157.9 ± 31.37 kg body weight) were randomly allocated to three dietary treatments (12 animals/treatment), with A. mearnsii and M. sativa replacing G. max (control diet) at 500 g/kg dry matter (DM) of diet. Steers fed the A. mearnsii diet had lower (P ≤ 0.05) DM intake, average daily gain, feed efficiency and carcass weights than those fed G. max and M. sativa diets with no difference found between G. max and M. sativa treatments (P > 0.05). Diet had no influence on any of the measured meat physicochemical traits (P > 0.05). Overall, steers fed the M. sativa and G. max diets had similar growth performance and meat yield, but higher (P ≤ 0.05) than that of steers fed the A. mearnsii diet. Current results suggest that M. sativa is a better alternative protein source to G. max for smallholder beef cattle compared to A. mearnsii.

The present study compared the effects of feeding dried grape pomace (DGP) or citrus pulp (DCP) at 150 g/kg dry matter compared to a control diet on major polyunsaturated fatty acids (PUFA), volatile and sensory profiles of beef. Feeding DGP or DCP diets to Angus steers for 90 d increased the proportions of C18:2n-6, C20:4n-6, C18:3n-3, total conjugated linoleic acid (CLA), n-3 and n-6 PUFA in muscle. Control-fed beef had greater concentrations of C18:1n-9, total aldehydes, ketones, and alcohols compared to DCP and DGP. Feeding DGP and DCP diets produced less tender beef than control. Overall, finishing steers on diets containing DGP or DCP compared to control increased proportions of total CLA, n-3 and n-6 PUFA, and reduced concentrations of aldehydes, ketones, and alcohols, but did not affect beef sensory attributes except for a slight reduction in tenderness.

Small ruminants significantly contribute towards livelihood, food and nutrition security for people living in semiarid low-to-middle-income countries. However, their productivity is largely constrained by feed shortages, prevalence of gastrointestinal nematodes (GIN) and postharvest meat losses. The current review explores the possibility of using sericea lespedeza (Lespedeza juncea var. sericea) as a natural helminth suppressant, feed ingredient and meat preservative for improving small ruminant health, meat production and shelf life. Sericea lespedeza has moderate contents of crude protein, fibre, minerals, vitamins, amino acids, and diverse composition of physiologically active substances such as condensed tannins, sterols and flavanols from which it derives nutritional, anti-bloat, helminth suppressant, antimicrobial and antioxidative properties. Overall, the present review demonstrates the potential of feeding sericea lespedeza to small ruminants as a sustainable means of controlling GIN and enhancing meat production and shelf life, while also reducing greenhouse gas (GHG) emissions. However, more research is required to determine optimal feeding strategies and doses for reducing GHG emissions while improving health, meat production and quality of small ruminants.

The process of consulting stakeholders, particularly farmers, in developing appropriate indicators for sustainability evaluation of low-input ruminant systems is often compromised by limited awareness and understanding of the sustainability concept by farmers in developing countries. Insights from farmers’ challenges present useful prospects for developing context-specific sustainability evaluation indicators for low-input ruminant systems. In the present review, a meta-analysis was used to develop farmer challenge-derived indicators for the sustainability evaluation of low-input ruminant farming system in sub-Saharan Africa. Key ecological challenges reported were low forage quality, poor soil quality, feed shortages and; economic challenges were low poor marketing structure, high cost of labour, and poor transport network, poor marketing infrastructure; and social challenges were rural to urban migration, lack of animal breeding management and inadequate access to information. The corresponding derived ecological indicators were biomass quality, soil quality, high winds; economic indicators were available marketing infrastructure, labour costs, transport networks; and social indicators were rural to urban migration, animal management training and access to information. The review shows that farmers’ challenges can be transformed to indicators for assessing the sustainability of the low-input ruminant farming system in sub-Saharan Africa.

As a complex and dynamic concept that requires understanding from an ecological, economic and socio-cultural perspective, sustainability of agriculture and food systems is currently being strongly promoted by many governments and rural development practitioners. However, advances in monitoring and evaluating the sustainability of low-input ruminant farming are hindered by a lack of tools that simultaneously consider the interrelationships and dynamic behaviour of the different components of the system. Here we report on the application of a system dynamics model to evaluate the sustainability of low-input ruminant farming systems. This draws on nine indicators grouped as ecological; (soil organic matter, water availability and biomass supply), economic; (livestock productivity, labour supply and household income, and social: (farmer training, credence attributes of ruminant grazing systems and gender equality) to describe system behaviour over a ten-year period. The outputs from model simulations were used to compute index values for each of the indicators and the indices were subsequently used to evaluate sustainability of low-input ruminant farming systems. Household income, gender equality and farmer training had the highest sustainability indices whereas, soil organic matter and biomass supply recorded the lowest values. Overall, the low-input ruminant farming system was found to be moderately sustainable.

The objective of the study was to determine growth performance, carcass characteristics and fatty acid composition of pigs fed on graded levels of Vachellia tortilis leaf meal (VTLM) diets. Forty-eight male Large White × Landrace finishing pigs with a mean (±standard deviation) body weight of 63.6 ± 0.73 kg (mean ± SD) aged 14 weeks were used. Pigs were allocated to individual pens in a completely randomized design and were assigned to six experimental diets containing 0, 30, 60, 90, 120, and 150 g/kg dry matter of VTLM. Each diet was offered ad libitum with fresh water to eight pigs in individual pens. There was a linear increase (P

The shelf-life of beef was compared from 7-months old Angus steers (281 ± 15.4 kg initial body weight) fed 150 g/kg DM dried citrus pulp (DCP) or grape pomace (DGP) for 90 days. The antioxidant activity, bacterial load, and lipid and protein oxidation were evaluated on the longissimus lumborum subjected to air-permeable packaging at days 1, 3, 5, 7 and 9 post-slaughter. Beef antioxidant activity was DGP > DCP > control (P ≤ 0.05). Beef from steers fed DGP or DCP had higher L* values (P ≤ 0.05) and fewer (P ≤ 0.05) coliform counts than steers fed the control diet. Beef antioxidant activity was DGP > DCP > control (P ≤ 0.05). Beef TBARS and carbonyl contents were DGP

Polyunsaturated fatty acids typically found in cattle feed include linoleic (LA) and α-linolenic acid (ALA). In the rumen, microbes metabolize these resulting in the formation of biohydrogenation products (BHP), which can be incorporated into meat and milk. Bioactivities of LA-BHP, including conjugated linoleic acid (cis (c) 9,trans (t) 11-18:2 and t10,c12-18:2) and trans fatty acid isomers (t9-, t10- and t11-18:1) have been investigated, but effects of several BHP unique to ALA have not been extensively studied, and most ALA-BHP are not commercially available. The objective of the present research was to develop methods to purify and collect ALA-BHP using silver ion (Ag(+)) chromatography in sufficient quantities to allow for convenient bioactivity testing in cell culture. Fatty acid methyl esters (FAME) were prepared from perirenal adipose tissue from a cow enriched with ALA-BHP by feeding flaxseed. These were applied to Ag(+)-solid phase extraction, and eluted with hexane with increasing quantities of acetone (1, 2, 10, 20%) or acetonitrile (2%) to pre-fractionate FAME based on degree of unsaturation and double bond configuration. Fractions were collected, concentrated and applied to semi-preparative Ag(+)-high performance liquid chromatography (HPLC) for the isolation and collection of purified isomers, which was accomplished using isocratic elutions with hexane containing differing amounts of acetonitrile (from 0.015 to 0.075%). Purified trans-18:1 isomers collected ranged in purity from 88 to 99%. Purity of the ALA-BHP dienes collected, including c9,t13-18:2, t11,c15-18:2 and t10,c15-18:2, exceeded 90%, while purification of other dienes may require the use of other complementary procedures (e.g. reverse phase HPLC).

The study evaluated shelf-life and sensory quality of meat from lambs fed finisher diets containing increasing levels of grape pomace (GP; 0, 5, 10, 15 and 20% GP/kg DM). Color, antioxidant activity and lipid oxidation of the longissimus lumborum were evaluated on different storage times (days 1, 3, 5, 7 and 9) post-slaughter using overwrapped air-permeable packaging. Treatments 0, 10 and 20% GP/kg DM were used for evaluation of protein oxidation and microbial counts on days 1, 5 and 7, while a trained panel assessed the sensory quality on day 1. Diet neither influenced meat color nor sensory quality. Diet × day interactions were observed for antioxidant activity, lipid and protein oxidation. Overall, the 20% GP/kg-diet finished lamb meat had the highest antioxidant activity and the lowest total viable bacterial counts, lipid and protein oxidation values during the shelf-life period. The 20% GP/kg DM in lamb diets, therefore, improved lamb meat shelf-life without negatively affecting sensory quality.

The current study examined the effects of inclusion of flaxseed in a red clover silage diet on growth, carcass quality, adipose tissue and muscle fatty acid (FA) profiles of beef steers. Twelve British×Continental crossbred steers (363±26.5 kg) were randomly assigned to two pens and fed diets containing 70% red clover silage, 15% steam rolled barley/vitamin–mineral supplement and either additional 15% steam rolled barley or 15% triple rolled flaxseed (all DM basis) for 215 d. Diet had no effect (P>0.05) on average daily gain or carcass quality atributes. Overall, FA profiles in all tissues followed similar trends when flaxseed was added to the diet but intramuscular fat had the highest proportions of n-3 and n-6 polyunsaturated FA (PUFA) while subcutaneous fat had largest proportions of conjugated linoleic acids (CLA) and perirenal fat had the highest proportions of trans-18:1 isomers, particularly vaccenic acid (VA). Feeding flaxseed increased (P

This study was conducted to determine fatty acid, amino acid and mineral composition of milk from Nguni and crossbred cows in South Africa. Milk samples from 8 Nguni and 8 crossbred cows grazing on rangeland were collected once per lactation phase, i.e. early lactation (January), mid lactation (April) and late lactation (June) in 2009 for milk composition analyses. Nguni cows had higher (P < 0.05) protein content, methionine, threonine, tyrosine, glycine and proline levels and n-6:n-3 ratio, and lower (P < 0.05) milk yield, fat and total solids content, potassium levels and total mono-unsaturated fatty acids (MUFA) than crossbred cows. Phosphorus levels were higher (P < 0.05) in milk from Nguni cows in the early lactation compared to crossbreds. In the early and mimd lactation stages, milk from Nguni cows had higher (P < 0.05) essential amino acids (arginine, phenylalanine, histidine, isoleucine and leucine), calcium levels and polyunsaturated fatty acids to saturated fatty acids (PUFA/SFA) ratios compared to crossbreds. Milk from crossbred cows in the mid and late lactations had higher (P < 0.05) C12:0, C14:0, C16:0 and C18:0 levels than Nguni cows. It was concluded that milk composition of Nguni cows is more desirable for the calf and human consumption, especially in the early-to-mid lactation compared to that of crossbreds.

The objective of this study was to determine fatty acid composition of beef from Nguni cattle supplemented with Acacia karroo leaf-meal. Thirty 19-month-old steers were randomly assigned to A. karroo leaf-meal (AK), sunflower cake (SF) and the control with no supplement (CN) diets. The m. longissimus thoracis et lumborum was sampled for analyses. Highest α-linolenic acid and docosapentaenoic acid, and lowest n −6/ n −3 ratios were recorded in beef from steers that received AK diet ( P P n −3 PUFA proportions were higher ( P P A. karroo in cattle diets can improve fatty acid composition of beef from a human health perspective.

Acacia karroo is one of the most widespread and abundant indigenous tree legume species in Southern Africa. The tree possesses positive attributes such as high growth rates, drought tolerance, adaptation to acidic infertile soils and resistance to large temperature variations. In the recent past, A. karroo was deemed to be a severe encroacher, which adversely affected land utilisation and rangeland productivity. Research attention has been diverted from its riddance as a weed to its utilisation as an animal feed. Widespread adoption of feeding strategies based on A. karroo was mainly impeded by the presence of thorns and tannins. Opportunities to minimise the adverse effects of these anti-quality factors are now well documented. A. karroo leaves have desirable fatty acid profiles, high N and mineral concentrations. At present, utilisation of A. karroo for beef production on rangelands is restricted by limited evidence regarding its feeding value. The current paper, therefore, demonstrates the potential of A. karroo to reduce worm burdens, and improve growth rates, carcass traits, beef quality and fatty acid profiles of cattle on rangeland. Economics of feeding A. karroo, strategies for incorporating it into feeding regimes for beef cattle and its relevance to sustainable livelihoods in low input production systems are outlined.

The objectives of the current study were to determine the effect of supplementing Acacia karroo leaf-meal on growth performance, blood chemistry and carcass characteristics of Nguni steers. Thirty 19-month old Nguni steers (241.5 ± 14.62 kg) were randomly allotted to three dietary treatments: A. karroo leaf-meal (AK), sunflower cake (SF) and control with no supplement (CN). Steers on the AK and SF diets were offered additional 150 g of protein through A. karroo and sunflower cake per day for 60 days. Serum concentrations of nutritionally-related blood metabolites were measured every fortnight. Steers that were given supplementary diets had higher (P 0.05) gross margins. It was concluded that A. karroo improves the nutritional status, growth performance, and carcass traits of Nguni steers reared on natural pasture.

A total of 218 structured questionnaires were administered to determine the influence of production and socioeconomic factors on Nguni cattle farmers' constraints in the smallholder areas of South Africa. Cattle were mainly used for cash, milk and ceremonies. Cattle herd sizes were higher ( P P P

Monitoring cattle inflows and outflows over time is a good indicator of herd productivity. In this study, ninety households were monitored for a year to determine the effect of season, rangeland type and herd size on births, purchases, sales, deaths, off-take, cattle production potential (CPP) and cattle production efficiency (CPE) in the sweet and sour rangelands of South Africa. Most births were recorded in large herds in the sour rangelands during the hot-wet season ( P P