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The aim of the study was to compare chemical composition and quality attributes of meat between male long fat tailed sheep (n = 17) and Small East African goats (n = 17) existing in Tanzania. Animals of 1.5 to 2 yrs in age and live body weight of 22.59±0.50 kg were purchased from livestock auction markets. Animals were fasted for 18 h and slaughtered according to standard halal procedure. Left carcasses were dissected into muscles, fat and bone and the muscle and fat were mixed together and chemically analysed. Meat quality attributes were measured based on Muscle longissimus thoracis et lumborum excised from right sides of carcasses. Goat carcasses had significant higher (p = 0.0302) moisture content (70.65% vs 66.96%) and lower (p = 0.0027) ether extract (2.49% vs 5.82%) than sheep but there was no significant species differences in protein and ash content. Sheep had lower (p = 0.0157) ultimate pH (5.74 vs 5.88) and higher (p = 0.0307) temperature (3.77°C vs 3.15°C) than goat carcasses. Sheep meat had lower (p = 0.0021) shear force values (29.83 N vs 34.07 N) than goat. Within species, at day 9 of ageing, meat tenderness improved (p = 0.0001) by 44.63% and 34.18% for sheep and goat. Pooled data showed that at d 9 of ageing, meat tenderness improved (p = 0.0001) by 39.25% (from 39.54 N to 24.02 N) compared to tenderness of meat which was not aged at day one of slaughter. The present study demonstrated the differences in chemical composition and quality attributes of meat existing between sheep and goats originated from East Africa.

An experiment using twenty-five bulls aged between 1 and 1·5 years and weighing 117 to 209 kg was carried out to estimate voluntary dry-matter intake (DMI), digestible dry-matter intake (DDMI), dry-matter apparent digestibility (DMD) and growth rate when the bulls were given 18 foods available from smallholder dairy farms on the slopes of Mount Kilimanjaro, Tanzania. The animals were randomly allocated to five groups of five animals each. Foods were then randomly allocated to the five groups for four periods of 60 days each during which DMI was measured. A digestion trial was made at the completion of each measurement. Outflow rates of solids from the rumen were determined by giving the animals 200 g Cr-mordanted fibre of each food and grab faecal samples were obtained. Dry matter (DM) degradation characteristics of the foods were determined in sacco in the rumen of three Boran steers fed on guatemala grass and the water soluble fraction (A) was measured. DMI varied from 2·2 kg for banana pseudostem to 4·77 kg/day for urea-treated maize stover. DMD ranged from 549 for untreated maize stover to 767 g/kg DM for banana pseudostem and growth rate ranged from 72 for banana leaves to 275 glday for urea-treated maize stover. Potential degradability (defined by A + B) (where B is the insoluble fraction degradable with time) for the DM ranged from 617 g for banana leaves to 874 g/kg DM for banana pseudostem and the degradation rate (c) ranged from 0·0168 for banana leaves to 0·0440 per h for green maize stover. The separate use of degradation characteristics A, B and c in multiple regression to predict DMI, DDMI, and growth rates gave better results than when A + B or (A + B) + c were used. Multiple correlation coefficients between degradation characteristics and DMI, DDMI and group rate were r– 0·90, 0·93 and 0·93 respectively. The results indicate that DMI, DDMI and growth rates by cattle fed on crop residues and forages could be predicted well using the rumen degradation characteristics of the foods.

SUMMARYIn previous work, administration of a commercial tannin preparation, quebracho, as oral drench was shown to reduce significantly faecal egg counts (FEC) and worm burdens of temperate sheep with experimental Haemonchus contortus infection. In the current work carried out in Morogoro, Tanzania, three separate animal trials were carried out to investigate the effect of drenches of wattle tannin (WT), a similar tannin preparation that is readily available in the tropics, on nematodes of tropical goats and sheep. In the first trial, 36 young Small East African (SEA) goats were experimentally infected with a single dose of mixed nematode larvae and FEC were monitored regularly. On day 30 post-infection (p.i.), the animals were blocked on the basis of their FEC and randomly assigned into three equal groups (n=12). For 3 consecutive days, two groups received low and high doses of drench at a rate of 1·2 and 2·4 g WT/kg bodyweight, respectively, whereas the third group received a placebo drench (i.e. water). All goats were humanely slaughtered on day 42 p.i. and their worm burdens were assessed. Neither FEC nor worm burdens were significantly reduced by the administration of the low or high dose of WT. The second trial had an identical design but two groups (n=14) of growing Black Head Persian (BHP) sheep were used instead. One group received the drench at 1·5 g WT/kg body wt for 3 consecutive days, whereas the other group received a placebo. Unlike in goats, worm burdens and FEC were significantly reduced (P<0·001) by the drench administration. In the third trial, the effect of WT drench against a naturally acquired nematode infestation in a flock of 34 BHP sheep was determined. FEC were examined three times in a 2-week period and the egg counts were used to block the sheep before being randomly assigned into two groups (n=17). The treated group received the drench at 1·0 g WT/kg bodyweight for 3 consecutive days, while the remaining half was given a placebo. The two groups continued to graze together as FEC were being monitored. Results indicated a significant (P<0·001) reduction in egg counts, which remained low for at least 3 weeks after the drench. The current study demonstrated that the WT drench had significant anthelmintic activity against important nematodes in sheep but not in goats, suggesting an existence of species differences between the two hosts. It was concluded that WT drenches could be used in combination with other worm control strategies to reduce or control nematode infections, at least in sheep.

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