A B S T R A C T Title: The relationship between histological structure and chemical composition i... more A B S T R A C T Title: The relationship between histological structure and chemical composition in leaves of forage grasses and legumes A study was conducted to determine the relation- ship between histological structure and chemical composition in leaf blades of the forage grasses Bouteloua repens and Bothriochloa pertusa and of the legumes Stylosanthes scabra, Desmodium barbatum and
Six adult African-type hair sheep (BW = 40.3 ± 6.3 kg) fitted with ruminal and duodenal cannu- la... more Six adult African-type hair sheep (BW = 40.3 ± 6.3 kg) fitted with ruminal and duodenal cannu- las were subjected to four treatments. Sheep were of- fered basal diets at a rate of 80 g of DM/kg of metabolic BW (equivalent to ad libitum access) consisting either of a low-quality grass hay (Brachiaria dictyoneura, 3.7% CP, DM basis) alone or
This study determined the nitrogen balance in two types of template pastures: a mixed pasture of ... more This study determined the nitrogen balance in two types of template pastures: a mixed pasture of two grass kikuyu (Pennisetum clandestinum) and tall fescue (Festuca arundinacea) pasture and the associated tall fescue grass and legume bird foot trefoil (Lotus uliginosus), in an area of 1 ha, with a completely randomized design with cow as the experimental unit and pasture treatment.
A B S T R A C T Title: Microbial in situ degradation of grasses and legumes leaf tissues and its ... more A B S T R A C T Title: Microbial in situ degradation of grasses and legumes leaf tissues and its realtionship with nutritional quality and precipitation A study was conducted to measure the in situ de- gradation of plant tissues and its relationship with forage chemical composition in leaves of the grasses Bouteloua repens and Bothriochloa pertusa and of
ABSTRACT The changes in the concentration of trans-vaccenic (C18:1 t-11) and rumenic (C18:2 c-9,t... more ABSTRACT The changes in the concentration of trans-vaccenic (C18:1 t-11) and rumenic (C18:2 c-9,t-11) acids in the milk from cows grazing on Pennisetum clandestinum, fed a supplement containing palm oil, rice bran or whole cottonseed were evaluated. Three supplements were assessed: one control supplement containing palm oil (C), with a low concentration of linoleic acid mainly from palm oil, and two supplements containing rice bran (RB) or whole cottonseed (CS) as the main source of linoleic acid. Six Holstein cows (4.2±1.7 years of age, 532.5±50.7 kg BW, 125±29 days in milk and a milk yield of 21.7±5.8 kg d −1 ; Mean±SD) were assigned to each treatment using a double 3 × 3 × 3 Latin Square Design. Compared with treatment C, the milk fat concentrations of trans-vaccenic acid (31.1 and 23.8 g kg −1 of fatty acids for RB and C, respectively), rumenic acid (14.1 and 11.3 g kg –1 of fatty acid for RB and C, respectively) and unsaturated fatty acids (348.7 and 325.4 g kg −1 of fatty acid for RB and C, respectively) were higher for RB. Compared with C and CS treatments, the Δ 9 -desaturase index was higher for RB (0.37, 0.35 and 0.34 for RB, C and CS, respectively) and the thrombogenicity index was lower (3.09, 3.43 and 3.50 for RB, C and CS, respectively). The atherogenicity index was lower for RB treatment compared with C, but not compared with CS (1.85, 2.03, 1.97 for RB, C and CS, respectively). Supplementing rice bran to grazing dairy cows is a good alternative for producing a kind of milk beneficial to human health, due to its higher concentrations of trans-vaccenic and rumenic acids, unsaturated fatty acids and lower thrombogenicity and atherogenicity indexes.
The effects of the offer of kikuyu grass and oats silage on production and compositional quality ... more The effects of the offer of kikuyu grass and oats silage on production and compositional quality of milk was evaluated using 18 Holstein cows in early and mid lactation, between 2 and 4 births, with a live weight (LW) of 585 kg and a milk production of 22.0 L/d. The experiment was carried out at Marengo Agricultural Center of the National University of Colombia. Three offers of silage (dry matter, DM); 0%, 0.7% y 1.4% of LW) were evaluated complemented with kikuyu grass in grazing to reach a total offer of 4%. The animals were supplemented daily with a balanced supplement. Kikuyu grass intake was estimated using chromium (external marker) and acid detergent indigestible fiber (internal marker). Kikuyu intake decreased (p < 0.001) to increase the proportion of silage in early and mid lactation cows. The milk production was affected by interaction kikuyu-silage offer, lactating stage and time of sampling (p < 0.01). Protein (0.2 units) (p < 0.05) and casein (0.35 units) conce...
A B S T R A C T Title: The relationship between histological structure and chemical composition i... more A B S T R A C T Title: The relationship between histological structure and chemical composition in leaves of forage grasses and legumes A study was conducted to determine the relation- ship between histological structure and chemical composition in leaf blades of the forage grasses Bouteloua repens and Bothriochloa pertusa and of the legumes Stylosanthes scabra, Desmodium barbatum and
Six adult African-type hair sheep (BW = 40.3 ± 6.3 kg) fitted with ruminal and duodenal cannu- la... more Six adult African-type hair sheep (BW = 40.3 ± 6.3 kg) fitted with ruminal and duodenal cannu- las were subjected to four treatments. Sheep were of- fered basal diets at a rate of 80 g of DM/kg of metabolic BW (equivalent to ad libitum access) consisting either of a low-quality grass hay (Brachiaria dictyoneura, 3.7% CP, DM basis) alone or
This study determined the nitrogen balance in two types of template pastures: a mixed pasture of ... more This study determined the nitrogen balance in two types of template pastures: a mixed pasture of two grass kikuyu (Pennisetum clandestinum) and tall fescue (Festuca arundinacea) pasture and the associated tall fescue grass and legume bird foot trefoil (Lotus uliginosus), in an area of 1 ha, with a completely randomized design with cow as the experimental unit and pasture treatment.
A B S T R A C T Title: Microbial in situ degradation of grasses and legumes leaf tissues and its ... more A B S T R A C T Title: Microbial in situ degradation of grasses and legumes leaf tissues and its realtionship with nutritional quality and precipitation A study was conducted to measure the in situ de- gradation of plant tissues and its relationship with forage chemical composition in leaves of the grasses Bouteloua repens and Bothriochloa pertusa and of
ABSTRACT The changes in the concentration of trans-vaccenic (C18:1 t-11) and rumenic (C18:2 c-9,t... more ABSTRACT The changes in the concentration of trans-vaccenic (C18:1 t-11) and rumenic (C18:2 c-9,t-11) acids in the milk from cows grazing on Pennisetum clandestinum, fed a supplement containing palm oil, rice bran or whole cottonseed were evaluated. Three supplements were assessed: one control supplement containing palm oil (C), with a low concentration of linoleic acid mainly from palm oil, and two supplements containing rice bran (RB) or whole cottonseed (CS) as the main source of linoleic acid. Six Holstein cows (4.2±1.7 years of age, 532.5±50.7 kg BW, 125±29 days in milk and a milk yield of 21.7±5.8 kg d −1 ; Mean±SD) were assigned to each treatment using a double 3 × 3 × 3 Latin Square Design. Compared with treatment C, the milk fat concentrations of trans-vaccenic acid (31.1 and 23.8 g kg −1 of fatty acids for RB and C, respectively), rumenic acid (14.1 and 11.3 g kg –1 of fatty acid for RB and C, respectively) and unsaturated fatty acids (348.7 and 325.4 g kg −1 of fatty acid for RB and C, respectively) were higher for RB. Compared with C and CS treatments, the Δ 9 -desaturase index was higher for RB (0.37, 0.35 and 0.34 for RB, C and CS, respectively) and the thrombogenicity index was lower (3.09, 3.43 and 3.50 for RB, C and CS, respectively). The atherogenicity index was lower for RB treatment compared with C, but not compared with CS (1.85, 2.03, 1.97 for RB, C and CS, respectively). Supplementing rice bran to grazing dairy cows is a good alternative for producing a kind of milk beneficial to human health, due to its higher concentrations of trans-vaccenic and rumenic acids, unsaturated fatty acids and lower thrombogenicity and atherogenicity indexes.
The effects of the offer of kikuyu grass and oats silage on production and compositional quality ... more The effects of the offer of kikuyu grass and oats silage on production and compositional quality of milk was evaluated using 18 Holstein cows in early and mid lactation, between 2 and 4 births, with a live weight (LW) of 585 kg and a milk production of 22.0 L/d. The experiment was carried out at Marengo Agricultural Center of the National University of Colombia. Three offers of silage (dry matter, DM); 0%, 0.7% y 1.4% of LW) were evaluated complemented with kikuyu grass in grazing to reach a total offer of 4%. The animals were supplemented daily with a balanced supplement. Kikuyu grass intake was estimated using chromium (external marker) and acid detergent indigestible fiber (internal marker). Kikuyu intake decreased (p < 0.001) to increase the proportion of silage in early and mid lactation cows. The milk production was affected by interaction kikuyu-silage offer, lactating stage and time of sampling (p < 0.01). Protein (0.2 units) (p < 0.05) and casein (0.35 units) conce...
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