• Asian-Australasian Journal of Animal Sciences
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• 제6권1호
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• pp.91-97
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• 1993

This experiment was carried out to examine the effects of urea-treated rice straw feeding on the growth performance of crossbred Holstein heifers under different feeding conditions. In the first experiment, the animals were given diets having 2 levels of TDN and CP and 3 levels of crude fiber (22, 30 and 36%) which were formulated with urea-treated rice straw and concentrates. Daily weight gain of heifers was not different between 22% and 30% CF diets, but the reduction of TDN or CP level to 90% of the requirements decreased the weight gain. Fiber content of 36% also reduced the body weight gain. The reduction of TDN significantly reduced DM intake and increased feed conversion ratio. Feed cost per kg weight gain was significantly increased by an increase in CF to 36%. In the second experiment, separate feeding and total mixing feeding were compared. There were no significant differences between the two feeding systems in body weight gain although the possibility of superiority in SF to TMF remained. DM intake was not affected by the feeding system, but 30% CF diet gave higher DM intake. Feed cost per kg weight gain was lower in the 30% CF diet.

• Asian-Australasian Journal of Animal Sciences
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• 제14권5호
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• pp.624-630
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• 2001

Two experiments on the effects of molasses additive on cassava tops silage quality to its feed intake and digestibility by growing Holstein$\times$local crossbred heifers were carried out. Sixteen plastic bags of one meter diameter and two meters length were allocated in a $2{\times}2$ factorial design with four replicates in the ensiling study, with and without the molasses additive and with two storage times (2 and 3 months). The silage produced in the first experiment was used in the feed intake and digestibility study. Six crossbred Holstein heifers, 160-180 kg live weight, were randomly allocated in a $3{\times}2$ change-over design to three treatments: Guinea grass ad libitum, 70% of grass ad libitum with a supplement of non-molasses cassava silage ad libitum, and 70% of grass ad libitum with a supplement of molasses cassava silage ad libitum. Ensiling was shown to be a satisfactory method for preservation of cassava tops. The HCN content was significantly reduced from $840mg\;kg^{-1}$ to 300 or $130mg\;kg^{-1}$, depending on storage period. The tannin content was not significantly changed. Molasses additive resulted in lower pH, Crude Protein (CP), NDF and higher DM content but did not otherwise affect chemical composition. The voluntary feed intake per 100 kg live weight of the heifers was 2.59, 2.65 and 2.91 kg DM of Guinea grass, non-molasses cassava tops silage and molasses cassava tops silage diet, respectively. Crude protein intake was significantly improved in the cassava tops silage diets. The apparent digestibility of DM, OM, CP, NDF and ADF decreased with the silage supplement diets. No significant difference in digestibility was found between the non-molasses and molasses silage diets. The digestibility coefficient of DM, OM, CP, NDF, ADF in non-molasses cassava tops silage and molasses cassava tops silage was 49.4, 52.1, 45.81, 36.6, 27.7 and 49.7, 51.9, 47.55, 28.1, 19.5, respectively. It is concluded that cassava tops can be preserved successfully by ensiling and that cassava tops silage is a good feed resource for cattle.

• Asian-Australasian Journal of Animal Sciences
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• 제21권1호
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• pp.66-74
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• 2008

Two experiments were conducted to assess the effect of replacing a conventional concentrate with mixed cassava (Manihot esculenta) foliage and legume (Phaseolus calcaratus) foliage. In Exp. 1, three rumen fistulated crossbred cows were used for in sacco rumen degradability studies. In vitro gas production was also studied. In Exp. 2, 11 crossbred F2 heifers (Red Sindhi$\times$Holstein Friesian), with initial live weight of $129{\pm}6kg$ and aged six months, were allocated in a Completely Randomized Design (CRD) to evaluate a mixture (ratio 3:1) of cassava and legume foliage (CA-LE feed) as a protein source compared to a traditional concentrate feed (Control) in diets based on fresh elephant grass (Pennisetum purpureum) and urea treated rice straw ad libitum. The Control feed was replaced by the CA-LE feed at levels of 0% (Control), 40% (CA-LE40), and 60% (CA-LE60) based on dry matter (DM). The in sacco degradation of CA-LE feed was higher than Control feed (p<0.05). After 48 h incubation the degradation of CA-LE feed and Control feed was 73% vs. 58% of DM and 83% vs. 65% of CP, respectively. The gas production of CA-LE feed was also significantly higher than of Control feed during the first 12 h of incubation. The results of the performance study (Exp. 2) showed that the level of CA-LE feed in the concentrate had no effect on total dry matter intake (p>0.05), but live weight gains (LWG) in CA-LE40 and CA-LE60 were significantly higher (551 and 609 g/d, respectively) than in the Control group (281 g/d). The intake of CP was higher (p<0.05) for the treatments CA-LE40 and CA-LE60 (556 and 590 g/d, respectively) compared to that of Control (458 g/d), while there was no significant difference in ME intake. The feed conversion ratio was 16.8, 9.0 and 7.9 kg DM/kg LWG in Control, CA-LE40 and CA-LE60, respectively. The feed cost of CA-LE40 and CA-LE60 corresponded to 43% and 35%, respectively, of the feed cost of Control feed. The best results were found when CA-LE feed replaced 60% of DM in Control feed and considerably decreased feed cost. It is concluded that feeding cassava foliage in combination with Phaseolus calcaratus legume as a protein supplement could be a potentially valuable strategy which leads to reduced feed costs and a more sustainable system in smallholder dairy production in Vietnam.