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Nigam S.N.,Indian International Crops Research Institute for the Semi Arid Tropics | Blummel M.,International Livestock Research Institute
Animal Nutrition and Feed Technology | Year: 2010

A total of 860 cultivars and breeding lines of groundnut grown in the off (Rabi) season of 2001/02 post rainy season at ICRISAT centre head quarter in India were investigated for haulm fodder quality traits and relationships between haulm traits and pod yields. Haulm fodder quality traits chosen were nitrogen (N x 6.25 equals crude protein), in vitro digestibility and in vitro metabolisable energy content. The haulm fodder quality traits were analyzed by a combination of conventional laboratory techniques and Near Infrared Reflectance Spectroscopy (NIRS). Significant (P<0.0001) and livestock nutritionally important cultivars differences were found for all three traits. Thus haulm nitrogen content ranged from 1.2 to 2.3%, in vitro digestibility ranged from 51.7 to 61.1%, and in vitro metabolisable energy content ranged from 6.9 to 8.8 MJ/kg. No inverse relationships were observed between any of the haulm fodder quality traits and pod and haulm yields. Haulm fodder quality analysis was repeated for 12 check cultivars in 2002 and over the two years broad sense heritabilities (h2) for nitrogen, in vitro digestibility and in vitro metabolisable energy content were 0.72., 0.72 and 0.67, respectively. The findings of the present study suggest that pod yield, haulm yield and haulm fodder quality traits can be simultaneously improved to develop better dual purpose groundnut varieties. Source

Favreau A.,French National Institute for Agricultural Research | Baumont R.,French National Institute for Agricultural Research | Duncan A.J.,International Livestock Research Institute | Ginane C.,French National Institute for Agricultural Research
Journal of Animal Science | Year: 2010

Previous work has shown that herbivores successfully learn to associate food sensory characteristics with postingestive consequences when the conditioning procedure is simple, whereas this ability breaks down when the learning task is made more complex. We hypothesized that sensory characteristics could act as indicators of postingestive consequences and that the presence of preingestive cues would improve the food learning of sheep in situations varying in complexity. Sixteen sheep were subjected to a first conditioning phase to associate 2 flavors added to alfalfa hay with either a positive or a negative consequence, induced by intraruminal administration of starch (330 mg/g of DMI) or LiCl (5 mg/g of DMI). Sheep progressively decreased their choice of the flavored hay associated with the negative consequence (P < 0.05). This procedure provided sheep with experience with postingestive consequences associated with the different flavors. In a second conditioning phase, the experienced sheep and 16 naïve sheep were divided into groups of 8 and subjected to either a simple or a complex conditioning procedure [i.e., the 2 flavors were offered on separate days (simple conditioning) or simultaneously within a day (complex conditioning)]. The 2 flavors applied to grass hay were associated with either positive (starch, 330 mg/g of DMI) or negative (LiCl, 10 mg/g of DMI) consequences. As hypothesized, sheep in the simple conditioning group expressed a greater aversion to the flavored hay associated with the negative consequence than did those in the complex conditioning group (0.303 ± 0.035 vs. 0.474 ± 0.035 respectively; P < 0.01). Experienced sheep rejected the flavor associated with the negative consequence more strongly than did naïve sheep, regardless of the conditioning procedure (0.304 ± 0.029 vs. 0.470 ± 0.041 respectively; P < 0.05). The initial increased preference for aniseed (0.80 ± 0.04), however, greatly influenced food learning because sheep negatively conditioned on this flavor expressed less avoidance than those negatively conditioned on orange (0.53 ± 0.04 vs. 0.25 ± 0.03 respectively; P < 0.01). In conclusion, the simultaneous scenario was actually perceived as complex by all sheep, and experienced sheep were more efficient in food learning than naïve sheep in both the simple and complex learning contexts. The sheep were thus able to generalize the association between sensory cues and postingestive consequences, especially in a complex environment, and then to use these sensory cues as indicators of postingestive consequences. © 2010 American Society of Animal Science. Source

Yayneshet T.,International Livestock Research Institute | Treydte A.C.,University of Hohenheim
Journal of Arid Environments | Year: 2015

Extensive livestock grazing is one of the most common and widespread forms of land uses in sub Saharan Africa (SSA). Studies assessing the effects of extensive livestock grazing on vegetation and soils in SSA are inconsistent in the direction and magnitude of study outcomes. We applied meta-analysis to identify whether studies so far conducted in the rangeland systems of SSA have detected significant rangeland degradation as approximated by changes in vegetation attributes (reduction in species diversity and richness; decreased biomass and ground cover; increased woody species density and canopy cover) and soil properties (Decreased soil OC, N and P). We quantified results of the included studies using the response ratio, which is the log proportional change in the means of a treatment and a control group. Four moderator variables (elevation (<1500 and ≥1500m above sea level); plant life form (herbaceous and woody), rainfall amount (<600mm and ≥600mm), rainfall modality (mono and bimodal), and soil texture (Loam, sandy, sandy loam)) appeared to affect the response of species diversity and richness patterns to different grazing regimes, i.e., communal grazing systems, exclosures, livestock ranches and game reserves. Species diversity and richness values were generally lower in the communal grazing systems compared to the other grazing regimes. Only three moderator variables (rainfall amount and modality, and soil texture) affected the herbaceous basal cover response. Differences in soil OC were highest between communal and exclosure areas, visible at high elevations and under high rainfall. Soil N was influenced by rainfall modality and soil texture. We conclude that the effects of grazing regimes onto the environment cannot be generalized but are specific across vegetation and soil variables and differ considerably with rainfall and elevation. © 2015 Elsevier Ltd. Source

Smajgl A.,CSIRO | Brown D.G.,University of Michigan | Valbuena D.,Wageningen University | Valbuena D.,International Livestock Research Institute | Huigen M.G.A.,University of Hohenheim
Environmental Modelling and Software | Year: 2011

Agent-based modelling has become an important tool to investigate socio-ecological processes. Its use is partially driven by increasing demand from decision makers to provide support for understanding the potential implications of decisions in complex situations. While one of the advantages of agent-based modelling is the ability to simulate the implications of human decision-making processes explicitly, methods for providing empirical support for the representation of the behaviour of human agents have not been structured systematically. This paper develops a framework for the parameterisation of human behaviour in agent-based models and develops twelve distinct sequences for the characterisation and parameterisation of human behaviours. Examples are provided to illustrate the most important sequences. This framework is a first step towards a guide for parameterisation of human behaviour in ABM. A structured discussion within the agent-based community is needed to achieve a more definitive guideline. © 2011 Elsevier Ltd. Source

Havlik P.,Kenya International Livestock Research Institute | Valin H.,International Institute For Applied Systems Analysis | Mosnier A.,International Institute For Applied Systems Analysis | Obersteiner M.,International Institute For Applied Systems Analysis | And 4 more authors.
American Journal of Agricultural Economics | Year: 2013

The livestock sector accounts for 30% of global land area and is a major driver of land use change. The price reductions generated by crop yield increases should, ceteris paribus, encourage farmers to replace some of the grass in ruminant rations with crops. This would lead to land sparing and related carbon dioxide emission reductions in regions where the feed productivity per unit of area is higher for cropland than for grassland. Six land cover types are distinguished in GLOBIOM: cropland, grassland, short rotation tree plantations, managed forest, unmanaged forest and other natural vegetation. Depending on the relative profitability of the individual activities, and on the inertia constraints, the model can switch from one land cover type to another. Comprehensive greenhouse gas accounting for agriculture and land use change is implemented in the model. Crop yield development will play a critical role in future land use dynamics. Indeed, it will determine the requirements for additional cropland, and also have a strong impact on grassland expansion. Source

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