Tên luận án: Phụ phẩm từ sắn là nguồn thức ăn tiềm năng trong chăn nuôi bò ở Cộng hoà dân chủ nhân dân Lào

Ngành: Chăn nuôi

Mã số: 9620105

Họ và tên nghiên cứu sinh:  Phanthavong Vongsamphanh

Giảng viên hướng dẫn:

- PGS.TS. Nguyễn Xuân Bả;

- TS. Đinh Văn Dũng

Đơn vị đào tạo:

Trường Đại học Nông Lâm, Đại học Huế

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THE NEW CONTRIBUTION OF THE DISSERTATION

Dissertation title: Cassava by-product as potential feed source for yellow cattle in Lao PDR

Major: Animal Sciences

Code: 9620105

Author name: Mr. Phanthavong Vongsamphanh

Supervisors:

- Associate Professor Dr. Nguyen Xuan Ba

- Dr. Dinh Van Dung

Institutions:  University of Agriculture and Forestry, Hue University

Contribution of the dissertation:

The research study was aim to improve utilisation of cassava byproducts in development of sustainable cattle feeding regimes in Lao PDR and other countries with similar conditions. There were four experiments presented on the dissertation. Experiments I, was evaluatr by test for finding the potential of feeding value of the storage cassava pulp in an open pit. Experiment II was study of intake, growrate in local yellow cattle by measure the response of cattle performance on bitter cassava foliage or/and brewers’ grains as a source of bypass protein and fiber supplements to cassava pulp-urea basal diet. Experiment III was to study gas and methane production in an in vitro rumen fermentation by evaluate the effect of different varieties of cassava leaves and supplementation with brewers' grains (0 or 4%) on methane production in an in vitro production of cassava pulp-urea as the main substrate and finally, experiment IV was to study the growth rate and to find out the most efficient/economic methodology for incorporating bitter cassava foliage as the protein-fiber source in the cassava pulp for a cattle fattening system. This is the first series of studies and the first scientific information in Lao PDR on utilizing locally available feed resources to manipulate rumen fermentation and thus to improve cattle performance.

Cassava pulp in open pit from cassava starch factory can be high potential feed interm of nutrition value and production for fattening cattle in Lao condition and could be used as basal diet.

The bypass protein and fiber source can be provide in the form of either: i) brewers’ grain or ii) bitter cassava foliage combine with brewers’ grain (50:50) give good performance supported the same growth of cattle.

In vitro rumen incubation of substrate of cassava pulp showed that methane production was decreased by supplementation with cassav leaves or bitter than sweet varieties; and by the addition of lower level of brewers’ grain of 4%.

Cassava pulp through various methologies such as separate, fermented and ensilage feed was shown to have poteintal for developing intensive fattening of cattle in feedlot and also in smallholders in Lao PDR.