This study characterized wheat straw feeding practices in smallholder farms using cross sectional survey and the results informed the design of an experiment to improve the nutritive value of wheat straw with urea and yeast culture treatment. Three diets tested in 49 days' feeding trial were farmers' rainy season feeding practice (FP), addition of urea to wheat straw at the time of feeding (USWS), and 14 days' incubation of straw with urea (UTWS). Yeast culture (15 g/day) was mixed with commercial dairy meal at the point of feeding. Survey data identified farmers' strategies in utilizing crop residues of which most important were improving storage facility (77.6%), adding molasses (54.5%), and buying a shredding machine (45.1%). On-farm feeding trial showed that intake was higher for UTWS than ( < 0.05) for USWS while milk yield was higher with FP than ( < 0.005) with UTWS or USWS but not different ( ≥ 0.05) between UTWS and USWS. Results imply that farmers feeding practices of crop residues may be improved for dairy cows' feeding and therefore UTWS could be used to support maintenance and milk production during dry season. Improving farmers feed storage facilities and training on incubation of wheat straw for dairy cattle feeding were recommended.

The study evaluated the effects of feeding urea treated/supplemented wheat straw-based diets with addition of yeast culture (YC) as a dry season feed for dairy cows. Wheat straw diets with 3.6% urea and 5.8% molasses were formulated to upgrade nonprotein nitrogen levels and fibre degradation in the rumen. Yeast culture was included at 0 and 10 g/cow/day in mixer with commercial dairy meal to improve on fibre degradation and milk yield. Two experiments were conducted. Firstly, an in sacco dry matter degradability (DMD) trial with three steers in a completely randomized design (CRD) with a 3 × 2 factorial arrangement to determine the effects on intake and rumen degradation parameters. Secondly, feeding trial with 18 lactating cows in a 3 × 2 factorial arrangement at two levels of yeast culture (0 and 10 g/cow/day) and three types of urea interventions: No intervention (WS); addition of urea to straw at the time of feeding (USWS); and 7 days incubation of straw with urea (UTWS). Yeast cultures addition had no effect on rumen pH and NH3-N, but urea intervention showed an effect on rumen pH with USWS being lowest (p < 0.05). Both urea interventions and yeast culture addition had no effect (p > 0.05) on dry matter intake, milk yield, and milk composition but they increased (p < 0.05) propionate yields.

In experiment 1, 4 treatments were prepared consisting of a mixture of chopped wheat straw in different proportions, a fixed proportion of poultry litter and 0, 15, 30 and 45% citrus pulp on a dry matter basis. The mixtures were ensiled for 60 days at room temperature in polythene bags. Ensiling (time effect) resulted in an increase (P<0.001) in titrable acidity level and a decrease in pH in the silage. In titrable acidity, there was an interaction effect (P<0.001) between the levels of citrus pulp and the ensiling time, such that there was an increase (P<0.001) in titrable acidity and a decrease (P<0.001) in pH in the 4 treatments both before and after fermentation. However, compared with the premix, there was a large increase in titrable acidity in silage following fermentation. Ensiling resulted in complete elimination of all coliforms in spite of their presence in large numbers in the mixtures before ensiling. Although the total nitrogen content was not affected, ensiling resulted in an increase (P<0.05) in the proportion of soluble nitrogen. The potential degradability of the silage dry matter ranged from 487 to 582 g/kg and increased (P<0.05) with the level of citrus pulp. In experiment 2, the daily intake of dry matter, organic matter, digestible organic matter and the digestibility of organic matter increased significantly with levels of citrus pulp in the basal silage diet, but there was no difference (P>0.05) in dry matter intake between diets containing 0, 76 and 167 g/kg citrus pulp when the intake was expressed on the basis of metabolic body weight. However, there was a decrease (P<0.001) in intake of silage and diet dry matter, organic matter and digestible organic matter when the level of citrus pulp in the basal silage diet increased from 167 to 272 g/kg. Only animals on the basal silage diet containing 167 g/kg citrus pulp had a higher (P<0.05) and positive nitrogen balance of 1.0 g/day. It is concluded that wheat straw and poultry litter can be ensiled successfully with citrus pulp to produce silage that is safe and of high fermentation quality. This silage has a medium to high feeding value in sheep, provided that the level of citrus pulp in the diet is in the range of 150–200 g/kg.

In a 4 2 factorial design, mixtures of wheat straw, poultry litter and citrus pulp with 0 and 5% molasses [T1 (75:25:0), T2 (60:25:15), T3 (45:25:30), and T4 (30:25:45)] were ensiled for a period of 60 days in 20 L laboratory silos. Inclusion of 5% molasses had no significant (P>0.05) effect on pH, neutral detergent fibre, acid detergent fibre, acid detergent lignin contents and in vitro organic matter (OM) degradability. However, molasses decreased (P<0.05) the concentration of volatile fatty acids including N-butyric acid. Coliforms were completely eliminated in all treatments, except in the silage without either molasses or citrus pulp. There was a difference (P<0.05) in titratable acidity levels between silage with 0 and 5% molasses. There was a decrease (P<0.001) in silage pH as the proportion of citrus pulp in silage increased from 0 to 30%. In vitro OM degradability increased (P<0.001) from 0.33 to about 0.56 as citrus pulp was increased from 0 and 45%. It is concluded that when silages are based on wheat straw and poultry litter, inclusion of molasses ensures favourable fermentation. However, in the presence of citrus pulp there was no additional benefit to the use of molasses.

Inadequate supply of glucose or glucogenic substrates to the body tissues can affect metabolism of absorbed acetogenic metabolites from the gut and therefore, influence feed intake in ruminants. This study investigated the effect of energy supplementation on rumen kinetics in the gut, and the acetate clearance rate in the body tissues of sheep fed low quality basal roughage. A basal diet consisting of urea-treated mixture of wheaten chaff and barley straw (3:1 DM) containing 22.2 g N/kg DM was used. Four Merino cross wethers weighing 45±4.38 kg fitted with permanent rumen and abomasal cannulae were allocated to four treatments in a 4×4 LSD. The treatments were basal diet (E 0 ), or basal diet supplemented with sucrose (112.5 g/d) administered intraruminally (E R ), abomasally (E A ), or via both routes (50:50) (E RA ). There was no difference (p>0.05) in the rumen liquid kinetics parameters between the four dietary treatments. However, there was a trend of animals supplemented with sucrose wholly or partly through the abomasum having lower faecal DM and therefore poor pellet formation, and low pH. Although the glucogenic potential of the fermentation products absorbed from the rumen was increased (p<0.001) by intra-ruminal supplementation with sucrose (E R and E RA ), there was no significant difference (p<0.05) in acetate clearance rate between the four dietary treatments.