Dairy cattle raising in Thailand is rapidly increasing due to government policy to support dairy extension and dairy production; for example the Dairy Extension Project for improving the structure of agricultural products; the Milk Consumption Campaign; the School Milk Program; the establishment of a dairy plants; bank loans to establish dairy farms, etc. According to statistics, the numbers of dairy farmers have increased, although even today milk production is insufficient to meet the rising demand, which is driven by population growth and the desire for a better standard of living. One of the constraints on the raw milk production is the high cost of inputs required in the production, in particular concentrate feed. Feed costs are about 70% of total operating costs, the largest being expenditure on concentrates (65 to 80 %), resulting in increasing costs of production, especially for small-holder farmers (Wanapat, 1995a). Feeding dairy cattle in the tropics is often difficult because of deficiencies in feed supply, in both quality and quantity (Wanapat and Devendra, 1992). However, using available crop residues in ruminant production to reduce the food – feed competition and build up a sustainable production system is a good strategy for development (Wanapat and Devendra, 1999; Preston and Leng, 1987).
All dairy cows in Thailand are crossbred Holstein-Friesian (HF), and most of them produce around 2,500 to 3,000 kg of milk/cow/year, with the number of cows ranging from 6 to 30 heads/farm (Chantalakhana and Skunmun, 2002). Practically 95-99% of dairy cattle in Thailand can be classified as being held by small scale or small-holder farmers under mixed crop-livestock farming systems (Wanapat, 1995b; Chantalakhana and Skunmun, 2002). Dairy operations are generally integrated with rice, sugar cane, cassava (Wanapat, 1995b), orchards, or some plantation crops (Chantalakhana and Skunmun, 2002).
Many tropical foliages or legumes contain secondary plant compounds, including crude saponins and/or condensed tannins, which have been shown to exert a specific effect against rumen protozoa, while the rest of the rumen biomass remains unaltered (Lu and Jorgensen, 1987; Getachew et al., 2000; Wang et al., 2000). Similarly, Ngamsaeng and Wanapat (2005) reported that supplementation of mangosteen peel at 100 gDM/day for cattle increased rumen bacterial and decreased protozoal populations, but maintained the fungal zoospore population. However, condensed tannins and saponins in mangosteen peel have not been investigated in lactating dairy cattle.
Local plants containing condensed tannins and/or crude saponins can be used as alternative dietary strategic supplements to improve rumen ecology and act as a defaunating sources in ruminants. Therefore, it is very important to determine the degradability and digestion of different feed resources supplemented for ruminants. However, limited information is available on the characteristics of DM and OM degradation of local feed resources for livestock in the tropics, with special reference to Thailand. In addition the combined use of sunflower oil and coconut oil in concentrates fed to dairy cows could be a way to meet their energy requirements and to improve the rumen ecology by reducing the protozoal population in rumen, as well as improving their milk yield and milk composition.
To evaluate rumen DM and OM degradabilities of local plant feed resources by using the in sacco technique.
To study the effect of mangosteen peel (Garcinia mangostana) by using sources of crude saponins and condensed tannins and sunflower oil and coconut oil as sources of fermentable energy and fat on rumen fermentation, milk yield and milk composition in lactating dairy cows.
To demonstrate strategic feed supplementation as an on-farm activity.
Chantalakahana C and P Skunmun 2002 Sustainable smallholder animal systems in the tropics. Kasetsart University Press, B.K.
Getachew G H, P S Makkar and K Becker 2000 Effect of polyethylene on in vitro degradability of nitrogen and microbial protein synthesis from tannin-rice browse and herbaceous legumes. British Journal of Nutrition. 84: 73-83.
Lu C D and N A Jorgensen 1987 Alfalfa saponins affect site and extent of nutrient digestion in ruminants. Journal of Nutrition. 117:919-927.
Ngamsaeng A and M Wanapat 2005 Effects of mangosteen peel (Garcinia angostana)
supplementation on rumen ecology, microbial protein synthesis, digestibility and voluntary feed intake in beef steers.
http://www.mekarn.org/msc2003-05/theses05/
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Wanapat M 1995b Nutrition strategies based on crop-residues to increase swam buffalo production and draft efficiency on farms. In: proceedings of an International Workshop on draft Animal Power. (Eds., M. Wanapat, S. Uriyupongson and K. Sommart). Khon Kaen University, Khon Kaen, Thailand.
Wanapat M and Devendra C 1992 Feeding and nutrition of dairy cattle in Asia. In:Proceeding of the 6th AAAP Animal Science Congress. 2, The Animal Husbandry Association of Thailand. Bangkok, Thailand. pp. 177-194.
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Wang Y, McAllister T A, Yanke L J and Cheeke P R 2000 Effect of steroidal saponin from Yucca schidigera extract on ruminal microbes. Journal of Applied Microbiology 88: 887-896.