Effect of protein supplementation and urea treatment on utilization of maize stover by Red Maasai sheep

Six Red Maasai sheep were used to investigate the effects of urea treatment and cotton seed cake supplementation of maize stover on intake, digestibility and rumen fermentation parameters. The basal feeds were Rhodes grass (Chloris gayana) hay (H), untreated maize (Zea mays) stover (US) and treated maize stover (TS), each of which was supplemented with 100 g of cotton seed cake (CSC) to make H+CSC, US+CSC and TS+CSC. These were offered over four feeding periods in a completely randomized block design, with periods serving as blocks. Hay and US treatments had similar intakes, digestibility, ruminal fluid volatile fatty acid (VFA) concentrations and pH. Urea treatment of the stover increased the digestibility of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fibre (NDF) and cellulose as well as the rumen ammonia nitrogen (AN) concentration. Cotton seed cake supplementation increased DM, OM and CP digestibility in US from 445 to 614 g/kg, 475 to 633 g/kg and 308 to 604 g/kg, respectively and VFA concentration in the rumen from 31 to 196 mmol/L. Supplementation of treated stover, increased the AN concentration (137 vs. 234 mg/l) rumen in the rumen content with no effect on nutrient digestibility and VFA concentration. The pH of the ruminal content for the diets ranged from 6.83 to 7.12. The trends of rumen AN and VFA for supplemented diets showed a gradual rise to a maximum three hours post-feeding, followed by a decrease in their respective concentrations. It was concluded that urea treatment and CSC supplementation of stover increased its utilization but supplementation of treated stover with CSC was not effective. Key Words: Sheep, Ruminal fermentation, Maize stover, Urea treatment SA Jnl Animal Sci Vol.34(1) 2004: 23-3

The role of dietary fibre in pig production, with a particular emphasis on reproduction

Abstract Fibres from a variety of sources are a common constituent of pig feeds. They provide a means to utilise locally-produced plant materials which are often a by-product of the food or drink industry. The value of a high fibre diet in terms of producing satiety has long been recognised. However the addition of fibre can reduce feed intake, which is clearly detrimental during stages of the production cycle when nutrient needs are high, for example in growing piglets and during lactation. More recently, fibre has been found to promote novel benefits to pig production systems, particularly given the reduction in antimicrobial use world-wide, concern for the welfare of animals fed a restricted diet and the need to ensure that such systems are more environmentally friendly. For example, inclusion of dietary fibre can alter the gut microbiota in ways that could reduce the need for antibiotics, while controlled addition of certain fibre types may reduce nitrogen losses into the environment and so reduce the environmental cost of pig production. Of particular potential value is the opportunity to use crude fibre concentrates as ‘functional’ feed additives to improve young pig growth and welfare. Perhaps the greatest opportunity for the use of high fibre diets is to improve the reproductive efficiency of pigs. Increased dietary fibre before mating improves oocyte maturation, prenatal survival and litter size; providing a consumer-acceptable means of increasing the amount of saleable meat produced per sow. The mechanisms responsible for these beneficial effects remain to be elucidated. However, changes in plasma and follicular fluid concentrations of key hormones and metabolites, as well as effects of the hypothalamic satiety centre on gonadotrophin secretion and epigenetic effects are strong candidates