Grazing behavior, dietary value and performance of sheep, goats, cattle and camels co-grazing range with mixed species of grazing and browsing plants

Abstract

A study was conducted to assess grazing behavior (GB), dietary value and performance of co-grazing sheep, goats, cattle and camels with initial body weights (BW) of 20.6 ± 2.09, 16.6 ± 0.97, 96.8 ± 3.43 and 162.3 ± 21.28 kg, respectively. Grazing lasted 16 weeks, using 6 growing animals per animal species. Animals co-grazed 6 ha of range containing grass, forb and browse species. GB observations for position and activity were made during day light. In weeks 4, 8 and 14 hand-plucked forages similar to that being selected by animal species were sampled for laboratory evaluation. BW was measured initially and at 28-days interval. Time allotted for feed consumption (grazing plus browsing), ruminating and idle was similar among animal species. However, camels and goats spent lower time grazing and higher time browsing than sheep and cattle. The CP content of hand-plucked forages was highest for camels (16.8%), intermediate for sheep (9.3%) and goats (10.2%) and lowest for cattle (4.5%); while NDF values took opposite trend. The IVDMD contents of forages took the trend of CP contents and were 55.8, 51.0, 43.6 and 72.8% for sheep, goats, cattle and camels, respectively. Daily BW gain was 34, 31, 94 and 358 g/day and BW change as percentage of initial BW was 19, 22, 11 and 26% for sheep, goats, cattle and camels, respectively, the former was higher for camels and the latter was lower for cattle. These results indicated reduced dietary overlap among animal species and consequently greater animal yield through co-grazing than perhaps could have achieved through mono-species grazing.