Variáveis fisiológicas de búfalas leiteiras criadas sob sombreamento em sistemas silvipastoris

Abstract

Resumo -O objetivo deste trabalho foi avaliar o uso de sistemas silvipastoris como ferramenta de manejo para manter as características fisiológicas de búfalas leiteiras e promover mais altos níveis de conforto térmico. Foram avaliadas 56 fêmeas adultas (79±44,12 meses; 575±92,90 kg): 30 em sistema silvipastoril sem sombra útil e 26 em sistema silvipastoril com 19,9% de sombra útil. Foram mensuradas semanalmente: frequência cardíaca e respiratória, temperatura retal e índice de conforto animal. As médias foram comparadas por análise de variância e as variáveis meteorológicas e fisiológicas foram correlacionadas pelo método de Pearson. O sombreamento diminuiu significativamente a frequência cardíaca e a temperatura retal. Em 71,4% das observações, os animais mantidos em sistema silvipastoril com sombreamento apresentaram índices de conforto próximos ao ideal. O sombreamento mantém os parâmetros fisiológicos de búfalas leiteiras mais próximos da normalidade e melhora o índice de conforto animal. A adoção de sistemas silvipastoris na produção de bubalinos, na região tropical, pode evitar gastos energéticos com termólise.Termos para indexação: Bubalus bubalis, Amazônia, bioclimatologia, conforto animal, ecofisiologia, sistema de pastejo. Physiological features of dairy buffaloes raised under shade in silvipastural systemsAbstract -The objective of this work was to evaluate the use of silvipastural systems as a management option to maintain physiological features of dairy buffaloes and to provide higher levels of thermal comfort. Fifty-six adult females (79±44.12 months; 575±92.90 kg) were evaluated: 30 in an unshaded silvipastural system and 26 in a silvipastural system with 19.9% of shaded area. Heart and respiratory rates, rectal temperature and animal comfort index were evaluated weekly. Means were submitted to analysis of variance, and meteorological and physiological data were correlated by Pearson's method. Shading significantly reduced heart rate and rectal temperature. In 71.4% of the observations, the animals kept in the silvipastural system with shaded area showed thermal comfort index closer to the ideal level. Shading maintains the physiological parameters of dairy buffaloes closer to normal, and improves the animal comfort index. The adoption of silvipastural systems for buffalo production in tropical areas can avoid energy loss due to thermolysis.

Evaluation of thermorregulatory capacity of dairy buffaloes using infrared thermography

“…Although the search for thermoregulation is observed in post-milking, it is also verified the necessity of focusing efforts on acclimatizing the pre-milking environment, since internal temperatures above buffalo thermal neutral zone are observed In a post-milking environment, shading becomes essential to minimize climate effects on these animals. A study of GARCIA et al (2011) corroborates with this affirmative; these authors observed that shading in a forest-pasture system significantly decreased heart rate and rectal temperature of dairy buffaloes. In 71.4% of the observations, animals kept in forest-pasture under shading demonstrated near-ideal comfort indices.…”

“…However, literature states that these animals have difficulty in releasing body-heat under high temperature and humidity, what can affect on productive and reproductive performance of this species (MARAI et al, 2009;GARCIA et al, 2011).…”

Hormonal changes in female buffaloes under shading in tropical climate of Eastern Amazon, Brazil

“…This result emphasises the importance of using trees in management systems to provide greater thermal comfort for animals (Moraes Júnior et al, 2010;Silva et al, 2011) and improve their yield (Castro et al, 2008;Moraes Júnior et al, 2010;Garcia et al, 2011). Incorporating trees into pastures in hot, humid climate regions favors the microclimate and provides better thermal comfort conditions, since shading can lower GTHI compared with areas under full sunlight (Garcia, 2013).…”

Tree species growth in a silvipastoral system in Amazon

“…In view of this problem, the integration of tree species with pastures in the ILPF system is presented as an option in order to recover the productive capacity of pastures (RozadosLorenzo et al, 2007;Paciullo et al, 2011), besides being essential to improve the quality of the pasture, and to contribute to the thermal comfort of the animals, resulting in better meat and milk production and also an increase in the nutritive value of the pasture (Dias-Filho, 2006). In addition, other types of animals such as buffaloes, sheep and goats can also be integrated into the silvipastoral system (Garcia et al, 2011;Campanha and Araújo, 2010). In the Amazon region, there are still few studies that deal with silviculture in forest plantations in ICLF systems, and there is a need for these systems to be developed in agricultural regions in Brazil areas so that in the coming decades, Brazilian agriculture and cattle raising can be promoted as an example of sustainability in the international market, in addition to offering healthy products, in line with new concepts regarding the timber market and land use systems (Silva, 2009).…”