32 N
.T. Mui et al. Livestock Production Science 66 2000 25 –34
significantly highest live weight gain P ,0.05, the The lower feed intake noted when the goats were
best FCR and lowest feed cost. There was an fed chopped cane stalk with the rind remaining
indication that when using 50.6 of the DM as indicates that the highly lignified outer rind has a
CWSC in the diet, i.e., replacing all GG with sugar negative effect on intake. Preston 1977 suggested
cane, the feed costs were reduced by 23 compared that the long fibres present in the rind act as a
to feeding only GG, but the lowest costs were limiting factor on intake. When the cane was chop-
obtained with 23 CWSC, which reduced the feed ped into 1–3-cm lengths these fibres were shortened,
costs by 40. which resulted in a higher intake. Slicing sugar cane
can also give the goats the possibility to select the more digestible components in the core of the stalk.
4. Discussion The animals on all the treatments consumed more
DM kg BW
than reported
by Devendra
and The harvesting time of sugar cane is concentrated
McLeroy 1982 for meat goats in the tropics 3– to 3–5 months in the dry season and the biomass
3.1, but less than was reported from India by yield is high, from 80 to 154 tonnes ha Mui et al.,
Gupta 1992, 4.35–4.42. Ashok and Wadhwani 1996. The annual biomass yield of GG varies from
1992 reported similar results, 3.05–3.66 and 3.77 60 to 150 tonnes ha depending on soil fertility and
of BW. However, the average DM intake per kg
0.75
altitude, with the majority of production in the wet W
was similar to the level recommended by
0.75
season. Although total production costs were higher AFRC 1998 for growing goats 66 g DM kg W
for sugar cane, the cost per unit of DM produced was daily, and these findings are in agreement with those
lower compared to GG Mui, 1993. With regards to of Gupta 1992, Shaer et al. 1996, Islam et al.
the period of availability and the production costs it 1997 and Shoo 1990.
is therefore interesting to look at the possibilities to Data from the digestibility trial indicated that the
replace at least part of the grass with sugar cane. average DM digestibility for the six treatments was
The results of the present studies showed that feed 65. Similar values were obtained by Gupta 1992,
intake by goats was highest when sugar cane tops Shaer et al. 1996 and Islam et al. 1997 when
and stalks were chopped into 1–3 cm. The green feeding different rations to growing goats. DCF
leaves could be fed at any length from 5 to 25 cm, declined when the level of CWSC increased in the
even whole to goats without any negative effect on diet, indicating that the fibre fraction from sugar cane
intake. These results are in agreement with findings has a lower digestibility than the fibre from GG.
in a study on cattle reported by Montpellier et al. The desired consumption levels of sugar cane
1977, where the voluntary consumption index was were not achieved but the actual levels were lower
lower when the stalks were chopped in pieces larger than planned. DM was fed in excess, more than
than 2 cm. Silvestre et al. 1976 studied treatments 200 of the consumption, and when there was a
consisting of chopping sugar cane stalk coarsely choice the goats evidently preferred the other feeds.
1–2-cm pieces or finely less than 0.5 cm and There was some difference in the intake values for
chopped cane tops into 4–5-cm lengths, and there the growth trial and the digestibility trial, but it
was a suggestion that feed intake was higher with the should be pointed out that the intake values in the
coarse chopping. The sugar cane in this experiment digestibility trial are based on fewer animals and a
was cut manually, but when a machine is used there shorter period of time than the growth trial, which
is normally a distribution of particle sizes and it may could explain the differences.
be difficult to detect the effect of chopping. Chop- The highest average daily gain, 65 g goat per day,
ping into small pieces can sometimes reduce intake was obtained with the diet including 23 of the DM
as it reduces the possibilities for selection. However, as sugar cane. These findings are in agreement with
sheep were able to select stover of higher nutritional those of Neckles 1988, who pointed out that when
value even when chopping length was short, unlike using diets of sugar cane for calves up to 150–200
cattle Osafo et al., 1997, which suggests that kg the best results should be expected at lower levels
anatomical differences between species are impor- of sugar cane, i.e., up to 30 sugar cane in the diet
tant. DM. Neckles et al. 1984 reported that using CWSC
N .T. Mui et al. Livestock Production Science 66 2000 25 –34
33 AOAC, 1985. Official Methods of Analysis, 12th Edition. As-
in beef and dairy cattle diets at 30–55 of diet DM
sociation of Analytical Chemists, Washington, DC, 957 pp.
was economically viable with regard to average daily
Ashok, M.P., Wadhwani, K.N., 1992. Feed-lot Performance of
gain and milk production. It should, however, be
Marwari Kids On Rations With Varying Proportion of Concen-
stressed that it is possible to feed a diet where the
trate and Roughages. Recent Advances in Goat Production. In: International Conference on Goats, March 1992 New Delhi, pp.
roughage consists of whole sugar cane only, but the
835–838.
growth will probably be lower even if the lack of
Castle, M.E., Retter, W.C., Watson, J.N., 1979. Silage and milk
protein is compensated for, because of the lower
production, comparisons between silages of different chopped
digestibility of the fibre in sugar cane.
lengths. Grass Forage Sci. 34, 293–301. Devendra, C., McLeroy, G.B., 1982. Nutrient requirements of
goats. In: Goat and Sheep Production in the Tropics. Longman Group, Singapore, pp. 61–68.
5. Conclusion
