2 results
Acacia saligna as a supplementary feed for grazing desert sheep and goats
- A. A. DEGEN, R. W. BENJAMIN, T. MISHORR, M. KAM, K. BECKER, H. P. S. MAKKAR, H. J. SCHWARTZ
-
- Journal:
- The Journal of Agricultural Science / Volume 135 / Issue 1 / August 2000
- Published online by Cambridge University Press:
- 01 August 2000, pp. 77-84
-
- Article
- Export citation
-
Acacia saligna, a leguminous tree, has a high crude protein content, remains green all year and can be grown in deserts using only runoff water. However, dry matter intake (DMI) by sheep and goats of A. saligna is low, presumably due to its high tannin content. It has been suggested that DMI could be increased by such methods as wilting of the forage and by neutralizing the negative effects of tannins by tannin-complexing agents. The purpose of this study was to determine DMI of supplementary A. saligna (phyllodes and small stems) by grazing sheep (∼ 50 kg) and goats (∼ 37 kg) when the animals were (1) offered wilted or fresh material (Expt 1); and (2) administered with polyethylene glycol (PEG), a tannin-binding agent (Expt 2). In this second experiment, there were three 14-day periods in which one group each of sheep and goats was on a regime of: No PEG–PEG–No PEG, whereas another group was on a regime of: No PEG–No PEG–PEG. In Expt 1, the DMI of A. saligna was statistically higher in goats than in sheep, but there was no difference in intake between fresh and wilted material. Average DMI of A. saligna, both fresh and wilted, was 124·1 g/day or 8·41 g/kg0·75 per day for goats and 94·1 g/day or 5·05 g/kg0·75 per day for sheep. Goats and sheep consuming fresh A. saligna gained more body mass than their respective controls; the difference was significantly greater in goats but not in sheep. In Expt 2, DMI of fresh A. saligna in the first period (before PEG) was 104·1 g/day or 7·16 g/kg0·75 per day for goats and 84·8 g/day or 4·51 g/kg0·75 per day for sheep. Administration of PEG during the second period resulted in an increase in DMI of 62% in goats and 83% in sheep. These animals maintained a high A. saligna intake in the third period when PEG was withdrawn. Goats and sheep that did not receive PEG in the second period had similar A. saligna intake as in the first period, but increased intake by 62% and 47%, respectively, with PEG in the third period. Overall, the two goat groups and two sheep groups consuming A. saligna lost less body mass than their respective controls; the difference was significantly less in sheep but not in goats. It was concluded that wilting A. saligna did not increase DMI. Administration of PEG increased A. saligna intake and the intake remained high after PEG was withdrawn. Offering A. saligna as a supplement had a positive effect on body mass change.
Effect of Acacia saligna with and without administration of polyethylene glycol on dietary intake in desert sheep
- A. A. Degen, T. Mishorr, H. P. S. Makkar, M. Kam, R. W. Benjamin, K. Becker, H. J. Schwartz
-
- Journal:
- Animal Science / Volume 67 / Issue 3 / December 1998
- Published online by Cambridge University Press:
- 02 September 2010, pp. 491-498
- Print publication:
- December 1998
-
- Article
- Export citation
-
The study was designed to measure (i) dry-matter intake (DMT) of sheep when diets including different tannins were offered and (ii) the effect of administration of polyethylene glycol (PEG), a tannin-binding agent, on DMI of tannin-rich diets. Acacia saligna phyllodes, a potential food for sheep, quebracho powder or tannic acid were added to a concentrate diet that served as a control and were offered to 16 ewe lambs (34·6 (s.d. 3·3) kg) that is, four lambs per diet. A. saligna has high levels of tannins; quebracho is a complex mixture of phenolic compounds in which condensed tannins predominate while tannic acid is a relatively pure example of a hydrolysable tannin. Intake was measured during four periods (I to IV) of 10 days each in which PEG was offered during periods II and IV. Food and water were available ad libitum. The DMI of the concentrate diet ranged between 925 glday and 1050 glday which was higher than for the other three diets (P < 0·05). The lambs consumed approximately 600 g dry matter (DM) of the diet that included 400 g A. saligna phyllodes per kg, and 500 g DM of the diets that included 100 glkg quebracho or 150 glkg tannic acid. With the quebracho and tannic acid diets, there was a distinct increase in intake when PEG was added and a decrease without PEG. This was not so with the Acacia diet when the intake remained high in period III without PEG and increased again in period IV with PEG. Body mass of control lambs increased in all periods and the increase was greater than in the other diets (P < 0·05). With the quebracho and tannic acid diets, there was an increase in body mass when PEG was added and a decrease without PEG. With the Acacia diet, there was a decrease in body mass in period I and an increase thereafter, even without PEG in period III.