P.O. Osuji

The effect of supplementing teff (Eragrostis tef) straw with graded levels of cowpea (Vigna unguiculata) and lablab (Lablab purpureus) hays on degradation, rumen particulate passage and intake by crossbred (Friesian × Boran (zebu)) calves

This study characterized the degradability of cowpea (Vigna unguiculata) and Dolichos lablab (Lablab purpureus) hays (trial 1) and the effect of these legumes on rumen ammonia concentration (RAC), particulate passage rate (k1) and intake (trial 2) and the degradability of teff (Eragrostis tef) straw (trial 3). Trials 1 and 3 were conducted using ruminally cannulated crossbred (Friesian × Boran) cows. In trial 1, cows were fed native pasture hay ad libitum plus 2.45 kg cottonseed cake head−1 day−1. In trial 2, calves were fed ad libitum teff straw alone or supplemented with three levels (0.5, 1 and 1.5% of body weight) of either cowpea or lablab hay. In trial 3, cows were fed teff straw ad libitum supplemented with either cowpea or lablab hay at 1% of body weight. Cowpea had similar degradation characteristics to lablab. Supplementation increased RAC (154–218 vs. 48 mg/l; P < 0.01), rate of degradation of teff straw (0.0257–0.0274 vs. 0.0138/h; P < 0.05), rumen outflow rate (k1) (1.48–2.09 vs. 1.18%/h; P < 0.05) and decreased the mean retention time (MRT; 72.8 vs. 109 h; P < 0.01). Total dry matter intake (DMI) increased with increasing level of supplementation. Cowpea and lablab had similar RAC, rate of degradation of teff straw, k1, MRT and DMI. It was concluded that both herbaceous legumes are equally efficient in alleviating nutrient deficiencies incurred when teff straw is fed to calves.

The degradability by sheep of fruits of Acacias and leaves of Sesbania sesban and the effects of supplementation with mixtures of browses and oilseed cake on the utilization of teff ( Eragrostis tef ) straw

This study was aimed at evaluating (1) the dry matter (DM) and nitrogen (N) degradabilities (by sheep) of Sesbania sesban leaves, Acacia albida (Faidhabia albida), A. siberiana and A. tortiris frazfs and (2) the effect of feeding a mixture of oilseed cake and tanniferous browses on the degradability of teff (Eragrostis tef) straw and oilseed cake and on particulate and liquid passage rates. Thirteen rumen cannulated sheep in a randomized complete-block design experiment were given teff straw ad libitum supplemented (DM per day) with 155 g oilseed cake (50: 50 mixture of noug (Guizotia abyssinica) and groundnut cake; oilseed cake diet) or with 92 g oilseed cake plus either 118 g S. sesban (sesbania diet) or 179 g A. albida fruits (albida diet). Diets were formulated to supply 10·5 g supplementary N per day. Sesbania had the highest DM washing loss, potential degradability and fastest DM degradation rate compared with the acacias. The N washing loss (g/kg) was highest for A. siberiana (500) followed by A. albida (431), A. tortilis (431) and sesbania (241). The potential N degradability (g/kg) was greater (P

Influence of feeding sheep on oilseed cake following the consumption of tanniferous feeds

This study evaluated the synergism between oilseed [50:50 noug (Guizotia abyssinica) and groundnut] cake (OSC) and tanniferous feeds (pods of Acacia albida and Sesbania sesban leaves) in two experiments. S. sesban has a lower content of soluble phenolics than A. albida pods (196 vs. 270 g/kg). Dietary treatments during trial 1 comprised teff (Eragrotis tef) straw given ad libitum supplemented per day with the following: 168 g of OSC alone (T1), or 100 g of OSC plus 135 g of sesbania leaves (T2) or 100 g of OSC plus either 50 (T3),100 (T4) or 200 g (T5) of acacia pods. During trial 2 dietary treatments comprised T1, T2, T5 and an additional treatment comprised 100 g sesbania leaves plus 200 g pods which were fed to sheep as a mixture. One strategy (sequence) was to give the OSC following complete consumption of either sesbania leaves or acacia pods while the other strategy (mixture) was to mix OSC with either of these forages before feeding. The sequence strategy was used in trial 1 while both strategies were used in trial 2. Each experiment used 30 sheep in a RCB design. During trial one incremental intake of pods resulted to linear increases (P 0.05) and substantial using the sequence strategy (23 g/day; P 0.05) for the sesbania and large (15 g/day; P<0.05) for the acacia diets. A comparison between the OSC–acacia mixture and acacia–sesbania mixture suggested that sesbania leaves could replace OSC with rather marginal increases in LWG. The discussion was structured to explain why the sequence strategy could offer a greater chance of interaction between tannin and OSC–protein than the mixture strategy and why such interaction was most probable with A. albida pods than with S. sesban. It was concluded that it is beneficial to feed sheep on OSC following the intake of tanniferous feeds as this could support superior LWG.

Integration of forage legumes with cereal crops. I. Effects of supplementation with graded levels of lablab hay on voluntary food intake, digestibility, milk yield and milk composition of crossbred cows fed maize–lablab stover or oats–vetch hay ad libitum

This study examined the effect of lablab hay supplementation of crossbred cows fed forages from cereal+forage legume intercropping (maize–lablab (ML) stover or oats–vetch (OV) hay) basal diets on feed intake, apparent digestibility, milk yield and milk composition of crossbred cows. Forty eight multiparous (parity 2–4) cows approximately 60 days prepartum and mean live weight 445 S.D.±57 kg at the beginning of the experiment were used in the study. The experiment lasted 200 days each cow, covering 60 days prepartum and 140 days postpartum. Lablab hay supplementation significantly (P 0.05) difference in total DM intake among the supplemented cows. Cows fed ML stover or OV hay supplemented with lablab hay had improved rumen environment as reflected in the rates of DM, OM, N and NDF degradation greater than 0.03 (i.e. 3%) per h. The degradation parameters; a, b, c and the effective degradability (ED) were higher (P 0.05) affect K intake in both ML stover and OV hay diets. OV hay and ML stover basal forages fed to unsupplemented crossbred cows resulted into average milk yields of 6.82 and 8.25 kg/cow per day, respectively, over a lactation period of 140 days after calving. Supplementation with lablab hay significantly (P<0.001) increased milk yield of crossbred cows fed OV hay but for ML stover based diets, supplementation was only significant (P<0.05) at the lowest level (0.4% BW) of lablab offer. For ML stover based treatments, the highest daily milk yield (9.5 kg/head) was obtained at 0.4% of body weight (BW) lablab hay supplementation, while for OV hay treatments, the highest milk yield of 9.7 kg/head was obtained at 1.2% BW lablab hay supplementation. Mean concentrations of milk fat, protein and total solids were similar for both ML stover and OV hay diets fed alone but lablab hay supplementation did not significantly affect the concentration of milk components of cows fed both forages. It was concluded that for optimum milk production from crossbred cows fed ML stover and OV hay basal diets, supplementation should be at 0.52 and 0.85% of BW level of lablab hay, respectively. The lack of response to higher levels of lablab hay supplement despite the increased protein intake was interpreted as resulting from a deficit of dietary energy.

Inoculation with adapted microbes versus addition of polyethylene glycol as methods to alleviate toxicity of Acacia angustissima leaves in sheep

Methods to alleviate the toxicity of Acacia angustissima (acc. no 15132) were evaluated in vitro and in vivo at ILRI Debre Zeit Research station in Ethiopia in 1997-1998. In an in vitro evaluation, A. angustissima leaves were incubated for 120 h with rumen fluid from Borana steers consuming native hay and cotton seed cake or from free ranging goat and sheep. Addition of polyethylene glycol (PEG, molecular weight (MW) 4000) increased gas production (4.9 v. 13.9 ml/100 mg dry matter (DM)), ammonia concentration (5.2 v. 9.7 mmol/l) and neutral detergent fibre (NDF) digestibility (380 v. 540 g/kg DM). In an in vivo experiment, Ethiopian highland sheep fed native hay and A. angustissima as a supplement (200 g/d) were inoculated with mixed rumen content from sheep gradually adapted on A. angustissima or were given PEG (MW 4000, 100 g/kg supplement) as methods to alleviate toxicity induced by A. angustissima. Sesbania sesban (acc. no 10865) with and without PEG were fed as a control. Effects on intake, apparent digestibility and nitrogen balance were studied in a 5 × 5 Latin square experiment. DM intake was increased by all the supplements (P < 0.001) even though hay intake was slightly reduced compared to hay only (P < 0.05). PEG increased intake of A. angustissima compared to inoculation. There were no significant differences in apparent DM or OM digestibility. Apparent nitrogen digestibility tended to be higher with S. sesban than with A. angustissima (P < 0.10) and addition of PEG increased it with A. angustissima (P < 0.05). Supplements increased ammonia and VFA concentrations and molar proportion of propionate (P < 0.05). Supplements tended to increase microbial nitrogen supply (P < 0.10) but there were no significant differences in efficiency of microbial synthesis. Supplements increased nitrogen retention (P < 0.01) but due to short periods there were no significant differences in the live weights of sheep. All the animals remained healthy during the experiment suggesting that both methods used alleviated the toxicity of A. angustissima. Addition of PEG was more effective than inoculation in increasing intake and nutritive value of A. angustissima.

Effect of fasting on the urinary excretion of nitrogen and purine derivatives by Zebu (Bos indicus) and crossbred (Bos indicus X Bos taurus) cattle

Abstract Osuji, P.O., Nsahlai I.V. and Khalili, H. 1996. Effect of fasting on the urinary excretion of nitrogen and purine derivatives by zebu (Bos indicus) and crossbred (Bos indicus x Bos taurus) cattle. J. Appl. Anim. Res., 10: 39–47. Six cattle [3 Boran (Bos indicus) and 3 crossbred (Bos indicus x Bos taurus)] were fasted for 20 days to estimate the effect of fasting on the excretion of nitrogen (N) and purine derivatives (PD) in the urine. PD excretion (y) for each genotype was related to time (t in days) by means of an exponential model: F=A+Be−kt where A is the endogenous excretion, k the fractional rate of excretion of exogenous PD B. The equations relating y to time (t) were: y = 0.172+0.178e−0.392t, R2 = 0.86; and y = 0.108 + 0.146e−0.108t R2 = 0.61 for the zebu and crossbred cattle, respectively. The daily fasting urinary nitrogen (N g/kg W0.75) was related to total daily PD excretion (y mmol/kg W0.75) by the equations: y = 0.00294 + 0.7285 ± 0.136 N, Adj R2 = 0.75 (crosses) y = 0.01099 + 0.922...

Integration of forage legumes with cereal crops. II. Effect of supplementation with lablab hay and incremental levels of wheat bran on voluntary food intake, digestibility, milk yield and milk composition of crossbred cows fed maize-lablab stover or oats-vetch hay ad libitum

Abstract This study examined the effects of lablab hay and graded levels of wheat bran supplementation on feed intake, feed degradation characteristics, apparent digestibility, milk yield and milk composition of crossbred cows fed forages from cereal crops+legume intercropping (maize/lablab (ML) stover or oats/vetch (OV) hay). Forty eight multiparous crossbred cows arranged in a randomised complete design with eight dietary treatments and six animals per treatment were used in the study. The dietary treatments comprised of either ad libitum ML stover+0.5% BW lablab hay or ad libitum OV hay+0.9% BW lablab hay, each supplemented with 0, 1.25, 2.50, and 3.75 kg DM of wheat bran. The combination of wheat bran and lablab hay as supplements to cows fed ML stover and OV hay basal diets significantly improved DM digestibility (P

The effect of feeding cottonseed cake, sesbania or leucaena with crushed maize as supplement to teff straw

Abstract This study was aimed at determining the effects of feeding an energy source on nitrogen utilization by Ethiopian Menzrams. Intake, digestibility, teff straw degradation, rumen pH and ammonia-nitrogen, nitrogen balance and purine derivatives were measured in the digestibility and nylon bag studies. All experimental sheep were offered teff straw basal diet ad libitum (unrestricted). With the exception of sheep fed the control diet, others received diets supplemented with either cottonseed cake (19.56), sundried sesbania and sundried leucaena (22 g dry matter kg −0.75 weight day −1 ) in addition to 45.5 g dry matter head −1 day −1 crushed maize. The supplemented diets improved ( P P P > 0.05). Cottonseed cake and sesbania seem to combine better with maize in terms of roughage intake and nitrogen utilization, respectively than with leucaena. The need to feed supplemented diets to ruminants was confirmed in this study.

Complementarity of bird-resistant and non-bird-resistant varieties of sorghum stover with cottonseed cake and noug (Guizotia abyssinica) cake when fed to sheep

A study was conducted to examine whether oilseed cakes (cottonseed cake (CSC) or noug (Guizotia abyssinica) cake (NSC)) are complementary to the bird-resistant (BR) and non-bird-resistant (NBR) varieties of sorghum stover and whether sheep select against morphological fractions containing high concentrations of tannins or proanthocyanidins (PA). Either 24 (growth study) or 16 (metabolism study) Ethiopian Menz sheep were used in a randomized complete block design to study the interaction of variety of sorghum stover with type of oilseed cake on feed selection, intake, digestibility, microbial protein synthesis, nitrogen (N) retention and growth. The degradability of the feeds and refusals was also determined. The NBR variety was more degradable than the BR variety during the early hours of incubation. NSC degraded faster, although to a lesser extent than CSC. Stover variety had no effect on ruminal ammonia concentration (RAC) while CSC induced a higher RAC than NSC did. Sheep given the NBR variety had more dust, less heads, less leaf, less sheath and more stem in their ingesta than those fed on the BR variety. It was seen that the sheep discriminated against the stems, since the ratio of stem in ingesta to stem on offer was < 1. Since PA are more highly concentrated in the sheath than in any of the other plant fractions, it appears that the choice of the morphological composition of the ingesta by sheep was not determined by PA. Sheep selected a diet which was 2-5% or or 5-11% more degradable than the offered or refused feeds, respectively. Relative to NSC, CSC enhanced the intake of N, N bound to neutral detergent fibre (NDF), digestibility and N retention and tended to increase (P < 0.06) liveweight gain (LWG) and organic matter (OM) intake but had no effect on microbial protein synthesis. Compared with the NBR variety, the BR variety depressed N digestibility and N retention, had no effect on microbial protein synthesis and on LWG, but depressed the efficiency of LWG by c. 30 %. Sheep given the BR + NSC diet had the lowest daily gain but excreted copious amounts of urine, probably in an attempt to eliminate toxic waste substances. Since sorghum is a crop of the semi-arid regions, it is quite likely that, although the bird resistance trait increases crop yield, it has resulted in a feed that is rather less suitable for livestock in this production environment, where water shortages are frequent. In-depth studies on the consequences of water shortage on the utilization of bird-resistant sorghum stover are required.

Digestible Organic Matter Requirements of Ethiopian Menz Sheep: Model and Application

Abstract Nsahlai, I.V., Osuji, P.O. and Umunna, N.N. 1997. Digestible organic matter requirements of Ethiopian Menz sheep: Model and application. J. Appl. Anim. Res., 11: 83–100. A static model for predicting either the growth rates or digestible organic matter (DOMI) required to meet predetermined levels of growth is developed. Parameters in the model were derived using data collected in ILRI-DZ laboratory from 6 growth studies (involving a total of 242 Ethiopian Menz sheep) supported by metabolism studies. DOMI = a W0.75 + WG/[Emax.e−k1w.f(WG)]; f(WG) = ek2.KW where a = 28.20 = Maintenance DOMI/kg W0.75 Emax = 0.949 = is the maximum WG that can be achieved per unit DOMI k1 = 0.0241 = fractional decline rates of the efficiency with increasing W k2 = 0.0070 = fractional decline rates of the efficiency with increasing WG W and WG = live weight and live weight gain, respectively. The performance of the model was tested using published data, There was a good agreement between the observed and predicted requi...