The Effect of Fertiliser Treatment on the Development of Rangelands in Argentina

In Argentina grazing of rangelands may result in a decrease in winter gramineous species with an increase in summer weeds such as Cynodon dactylon. Lolium multiflorum is an important forage resource for grazing in the autumn, winter and spring. A delay in its emergence may occur because of summer weeds, which reduces the germination rate. The proportion of the seed bank as ryegrass allows the recovery of natural grassland and facilitates an increase in the productivity of livestock. The objective of this study was the evaluation of the impact of application of fertiliser in the short term on the relationship with botanical composition at different herbage availabilities

Effect of Caloric Stress on Milk Production and Animal Comfort

The objective of this study was to determine the effect of the environmental factors on the animal behaviour of grazing dairy cows, estimated through the THI (Temperature-Humidity Index) and the relationship with the daily milk production, quality of milk, consumption and the detection of zeal. The study was carried out in Azul , in the province of Buenos Aires, Argentina and was developed from December 1999 to February 2000. The effect of the half shade was quantified based on the production in litres of milk/day, % protein, % fat and detection of zeal. In the period analyzed, the THI usually surpassed the values tolerated by the animal, generating different stress levels that were attenuated with artificial shades

Phenotypical Characters Associated with the Loss of the Seed and the Production of Biomass in \u3ci\u3ePanicum coloratum\u3c/i\u3e var. \u3ci\u3emakarikariense\u3c/i\u3e

Since the beginning of humanity, plants have been manipulated by humans by artificial selection to obtain changes in their characteristics. This progress has been achieved through the domestication of the species. Panicum coloratum is a species of summer perennial grass, megathermic, tolerates waterlogging, cold and slightly saline soils. It is of African origin and used as fodder in various parts of the world. In Argentina around 130.500 hectares are sown, the most widespread varieties are: var. coloratum, and var. makarikariense Goossens. Its characteristics of determined flowering and ununiform ripening within the panicle, added to a very low retention of the seeds after maturation, establish serious difficulties in harvesting quality seeds. Megathermic forage species are good producers in forage quantity and, in turn, possess good quality. The objective of the work was to study the dynamics of seed dehiscence and the forage production of two cultivars of Panicum coloratum var. makarikariense (cv. Kapivera and cv. Bambatsi). The seed fall was evaluated weekly for 70 days between March-May 2017 and 2019 on 15 random inflorescences of each cultivar. Once the seed harvest was completed in May 2017 and 2019, the panicles were cut and the panicle height, panicle length, rachis length, wet weight, dry weight and percentage of dry matter were analyzed. Through a χ² distribution, it was found that there is experimental evidence that indicates that the dynamics of seed fall are different among cultivars. An analysis of main components was carried out in each year under study to simultaneously evaluate all the variables related to biomass, in the two ACPs mentioned there was not a defined grouping of the plants according to the cultivation to which they correspond