Rangelands are the mainstay of cattle and sheep systems in Uruguay. The current demand for global results from different grazing systems puts pressure on the generation of new knowledge. In this context, spring droughts in Uruguay are one of the most relevant challenges for livestock farmers. The objective of the following work is to evaluate the impact of drought on a continuous grazing with breaks with and without inclusion of a rotational grazing module system. The study was conducted during the 2021 /2022 and 2022 /2023 seasons, with the former encompassing a spring drought and the latter a severe spring and summer drought, examined two grazing systems: continuous grazing with breaks (CG) and continuous grazing with breaks plus rotational grazing module (CGR). The results showed that Aboveground Net Primary Productivity (ANPP) decreased by about 12% in both groups. The Meal Plate Index (MPI), an index that relates available grazing to the grazing required for optimal animal performance, decreased by 13% in CG and 7% in CGR. Grass Availability (GA) also decreased by 15% and 4% for CG and CGR respectively. The proportion of pasture greater than 5 cm (PRG5) decreased from 19% to 12% for CG and increased from 26 to 33% for CGR for both seasons. The main differences are that CGR maintains Meat Production (MP) (105-107 Kg per hectare) and Efficiency per Stock Unit (MPES) (133-132 kg). On the other hand, CG was not able to maintain its MPES (144-128 kg), which decreased by 12%. For CG, 9 out of 12 were negatively affected, resulting in a 22% decrease of MP. Within CG, the least affected had values of PRG5=16 and MPI=0.72, while the most affected had values of PRG5=7 and MPI=0.6. The severe drought had a differential impact on systems, CGR group showed improved levels of grass indicators and reduction in the negative impact on M P and MPES.
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