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Articles 1 - 9 of 9
Full-Text Articles in Physical Sciences and Mathematics
Using Cuticular Wax Alkanes And Computer Simulation To Estimate Diet Selection, Herbage Intake And Nutrient Cycling In Grazing Sheep, H Dove, R J. Simpson
Using Cuticular Wax Alkanes And Computer Simulation To Estimate Diet Selection, Herbage Intake And Nutrient Cycling In Grazing Sheep, H Dove, R J. Simpson
IGC Proceedings (1997-2023)
In grazing ewes, plant cuticular wax alkanes were used as markers to estimate diet selection, herbage intake, N intake and N excretion in faeces. Pasture and animal data were then used as inputs to the decision-support system GrazFeed, which simulates grazing and digestion to predict herbage intake, N intake and N excretion. Estimated and predicted intakes agreed closely, especially for N intake, and it is concluded that, subject to further investigation of the possibility that GrazFeed slightly under-estimated faecal N excretion, the close agreement between estimated and predicted OM and N intakes suggests that this combined use of alkane methods …
Foraging Behavior Of Zebu Cattle Grazing Deciduous Forest, L Ortega, J Castillo, F Rivas
Foraging Behavior Of Zebu Cattle Grazing Deciduous Forest, L Ortega, J Castillo, F Rivas
IGC Proceedings (1997-2023)
The objective of this study was to determine whether the foraging behavior of Zebu cattle in deciduous forest was affected by time of the year. Data were recorded during the wet, nortes and dry seasons. Ten Zebu cows were used to record biting rate. Intake and bite size was estimated using three esophageally fistulated animals. Cattle browsed shrubs and trees in the wet season and ingested litter leaves in the dry season which resulted in differences of ingestive behavior. In general, bite size and intake were higher in the wet season and decreased during the nortes and dry seasons.
Intake And Diet Selection By Sheep Grazing Grass/Clover Patches, I J. Gordon, A W. Illius
Intake And Diet Selection By Sheep Grazing Grass/Clover Patches, I J. Gordon, A W. Illius
IGC Proceedings (1997-2023)
The effects of the spatial dispersion of ryegrass (Lolium perenne L) and clover (Trifolium repens L), at the feeding station scale, on diet composition and feeding behaviour were studied for sheep. There were no significant changes in diet composition with changes in the spatial dispersion of sward components. Bite size, bite rate and intake rate did increase as the species became more aggregated.
Modeling Intake Of Grazing Cows Fed Complementary Feeds, D R. Buckmaster, L A. Holden, L D. Muller, R H. Mohtar
Modeling Intake Of Grazing Cows Fed Complementary Feeds, D R. Buckmaster, L A. Holden, L D. Muller, R H. Mohtar
IGC Proceedings (1997-2023)
A model suitable for predicting intake for grazing or non-grazing dairy cows is presented. The model integrates the potentially intake limiting factors of physical fill, physiological energy demand, wet mass, herbage availability, herbage cover, and grazing time. Integration of these factors with a simple set of linear ration balancing constraints yields a model suitable for predicting supplemental feed requirements as well as potential animal production from a grazed land. The model is semi-theoretical, being descriptive in structure, but containing empirical relationships.
Intake And Quality Of Panicum Maximum (Cv. Gatton) Receiving Different Levels Of Nitrogen During Autumn, W.A. Van Niekerk, N F.G. Rethman
Intake And Quality Of Panicum Maximum (Cv. Gatton) Receiving Different Levels Of Nitrogen During Autumn, W.A. Van Niekerk, N F.G. Rethman
IGC Proceedings (1997-2023)
The objective of this study was to investigate the influence of N fertilization on the quality of Panicum maximum cv. Gatton (Panicum) and the subsequent intake thereof. Hand cut samples increased in N (1.8 - 2.7%) and NO3-N content (0.75 - 1.54%) and decreased in WSC (14.6 - 13.9 g/kg) content, but with no changes in IVDOM as N fertilization levels raised from 0 to 150 kg N/ha respectively. No changes occurred in the NDF and ADL values. The animal selected N, and IVDOM values were higher and NDF value lower than the hand cut samples, which was expected due …
Intake And Partial Digestibility Of Panicum Maximum (Cv. Gatton) At Three Stages Of Maturity During Summer, W.A. Van Niekerk, N F.G. Rethman
Intake And Partial Digestibility Of Panicum Maximum (Cv. Gatton) At Three Stages Of Maturity During Summer, W.A. Van Niekerk, N F.G. Rethman
IGC Proceedings (1997-2023)
The objective of this study was to determine the influence of stage of maturity on the intake and digestibility of P. maximum (cv. Gatton) during the active growing season. Low DM content at the young and medium growth stages (24.9 and 25.2%) did not hamper DOMI (48.8 and 44.1 g/kg W0.75/d) respectively. The N concentration of the three stages were well within the limit required for optimal rumen microbial production (1.8 - 2.0%). The high NDF value of the adult stage (59.5%) resulted in a significantly lower IVDOM value (62.3%) but the IVDOM values of all stages were on the …
Effects On Intake Of Supplementing Low-Quality Roughage With Protein-Rich Feeds, J.J. M.H. Ketelaars, G A. Kaasschieter, M Kane
Effects On Intake Of Supplementing Low-Quality Roughage With Protein-Rich Feeds, J.J. M.H. Ketelaars, G A. Kaasschieter, M Kane
IGC Proceedings (1997-2023)
Intake responses of ruminants to supplementation with protein-rich concentrates or legume hays have been related to the ratio of nitrogen (N) content and organic matter digestibility (OMD) of the basal feed. Marginal intake effect of supplements, i.e. change of organic matter intake (OMI) from the basal feed per unit OMI from supplement, decreased on average from 1.7 to 0 and -0.8 g. g-1 at N/OMD of 0.010, 0.016 and > 0.030 g. g-1, respectively. Marginal effect of supplements defined as change of total digestible organic matter intake (DOMI) per g DOMI from supplement was 2.5, 1 and 0.3 g. g-1 for …
The Effect Of Sward Height And Bulk Density On Herbage Intake And Grazing Behaviour Of Dairy Cows, C S. Mayne, D Mcgilloway, A Cushnahan, A S. Laidlaw
The Effect Of Sward Height And Bulk Density On Herbage Intake And Grazing Behaviour Of Dairy Cows, C S. Mayne, D Mcgilloway, A Cushnahan, A S. Laidlaw
IGC Proceedings (1997-2023)
The effects of sward height and bulk density on herbage intake and grazing behaviour of dairy cows during 1 hour grazing periods was investigated. Sward factors had a marked effect on dry matter (DM) intake/bite, which ranged from 0.4 to 1.1 g, and this was reflected in hourly intake rates. Intake/bite was largely influenced by sward height, reflecting increased bite depth in taller swards, with inherent differences between swards at low sward heights largely attributable to differences in bulk density (BD). The results indicate that DM intake rates up to 4.0 kg DM/hour can be achieved in short term grazing …
Intake, Relative Palatability Indices And Blood Parameters Of Vetch Varieties As A Component Of Goat Diet, N. H. Msiza, K. E. Ravhuhali, H. K. Mokoboki, Sydney Mavengahama, G. M. Chelopo
Intake, Relative Palatability Indices And Blood Parameters Of Vetch Varieties As A Component Of Goat Diet, N. H. Msiza, K. E. Ravhuhali, H. K. Mokoboki, Sydney Mavengahama, G. M. Chelopo
IGC Proceedings (1997-2023)
Therefore, the objective of this study was to assess the feed intake, relative palatability indices and blood parameters of vetch varieties as a component of goat diet. The field and palatability study was carried out at the North West University, Molelwane Farm, North West province, South Africa. Ten weaner goats (16 ±2 kg) were used in this experiment. Four feeds (Vicia sativa – common & volga vetch ), Vicia villosa Roth (haymaker plus vetch) and buffalo hay grass were used in this experiment and each goat was exposed to these treatment diets. A cafeteria feeding method was used, allowing …