Alterações renais de ovinos alimentados com genótipos de palma forrageira resistentes à cochonilha do carmim (Dactylopius opuntiae)

Abstract

The aim of this work was to assess the effect of two varieties of cochineal-resistant cactus cladodes through histopathology and histomorphometry of the renal parenchyma in sheep. Thirty-six lambs (22.0 ± 2.9 kg of body weight) were randomly distributed to a completely randomized design with three treatments and twelve repetitions. Over 86 days, the animals were fed a control diet containing Tifton hay as exclusive roughage (60% of dietetic DM) and two other diets where 75% of the hay was replaced by cactus cladodes (genotypes “Miuda” or “Orelha de Elefante Mexicana - OEM”). Blood samples were drawn 45 days post-feeding to determine indicators of energy and protein metabolism, and liver fragments were collected after slaughter for histopathological and histomorphometry analyses. Histopathological findings included nephrites, glomerular proteinosis, and tubular proteinosis. However, it is worth noting that lesions found in lambs fed cactus cladodes did not differ (p>0.05) between the genotypes studied. For histomorphometry analysis, there was an effect of the experimental diets (p<0.05) on area volumes of renal corpuscle, renal glomerulus, and Bowman’s capsule. Therefore, it can be concluded that lesions in renal parenchyma were present, but tissue damage was not outstanding in lambs fed either of cactus cladodes genotypes over 86 days.