Sweet potato as a ruminant feed: Performance of sheep fed mixtures of the forage and root.

Scarcity of quality forage during the dry season poses a serious problem to ruminant production in southwest Nigeria. Dried sweet potato (SP) vine and root have the potential to bridge the gap in feed supply for ruminants during this period. In a feeding trial, fifteen male West African dwarf (WAD) sheep were used to estimate the nutritive value of SP forage and root as a basat feed for ruminants during the dry season. Experimental diets consisted of SP forage and root in the following proportions, 0:100, 25:75, 50:50, 75:25, and 100:0 (forage. root). In the first part of the trial, growing WAD sheep were fed experimental diets for twenty weeks. Dry matter (DM) intake and growth rate of the animals were measured in the second part, digestibility and nitrogen balance of sheep fed the experimental diets were measured. Intake, growth rate, digestibility and nitrogen retention improved significantly (P < 0.05) when SP forage and root were mixed in the diet. The DM intake ranged from 1.8 to 4.9% body weight; growth rate, -34.1 to 86.43 g/day; DM digestibility, 64.6 to 70.4%; and nitrogen retained, 29.5 to 51.0%. Performance, digestibility and nitrogen utilization of WAD sheep was highest when SP forage and root formed equal proportions (50:50) in the diet. Mixing SP forage and root in the diet proved beneficial to growing sheep and equal proportions of the forage and root in the diet appear to be the most appropriate combination.

A dietary assessment of colonial Cape Town’s enslaved population

There is a growing body of bioarchaeological research on eighteenth and nineteenth century colonial Cape Town, a significant node in the transportation networks of both the Indian and Atlantic oceanic slave trades, attempting to shed light on the lives of enslaved persons. Here, a preliminary archaeological isotopic dietary baseline for the colonial Cape is presented. It is apparent from the data that cattle tended to graze far inland from Cape Town in an arid C3-C4 to purely C4 biome. Sheep/goats grazed close to the settlement or some distance away in C3 to C3-C4 biomes. A qualitative comparison of the baseline data to that of enslaved persons at The Cape suggests that this population did not consume large amounts of marine protein as has been concluded in the past. The archaeological baseline data was utilised, in combination with published modern data, to create a quantitative dietary reconstruction of a subset of this population using a Bayesian multi-source diet mixing model (FRUITS). The reconstruction confirms that the Cape’s enslaved did not consume much marine protein but relied predominantly on terrestrial C3 plant protein.

Preference of Boer goats for Namibian native forage legumes and Lucerne (Medicago sativa)

The objective of this study was to determine the relative palatability of four native forage legumes (Otoptera burchellii, Crotalaria argyraea, Crotalaria podocarpa and Vigna lobatifolia) in comparison with each other and with Lucerne (Medicago sativa). Eight weaned Boer goats aged 6 months and weighing 25.2 ± 4.9 kg were grouped by sex, and then randomly allocated to individual pens. Goats were simultaneously offered 100 g of each of the four native legumes and 600 g of M. sativa (as-is basis) over a 10-day period. Grass hay (Cenchrus ciliaris), fresh water and mineralised salt licks were available at all times. Grass hay was given to allow diet mixing and possibly ameliorate any undesirable effects, such as bloat, due to feeding on legumes alone. The percentage of each species consumed of that offered was associated (P &lt; 0.001) with legume species, day and legume × day interaction. Over 95% of the O. burchellii, V. lobatifolia and Lucerne offered were consumed from Days 1 to 10. The amounts of Crotalaria spp. consumed fluctuated widely in the first 4 days, but increased thereafter to &gt;95% of that offered. This study demonstrated that hay of all the four native forage legume hays were palatable to Boer goats, with the inferred ranking being: (Lucerne, V. lobatifolia) &gt; O. burchellii &gt; Crotalaria spp. Further studies are required to investigate the productivity of goats feeding on these native forage legumes, which have potential for use in marginal lands.