Investigation of the protective effect of chitosan against arsenic-induced nephrotoxicity and oxidative damage in rat kidney tissue.

Arsenic is an important metalloid that can cause poisoning in humans and domestic animals. Exposure to arsenic causes cell damage, increasing the production of reactive oxygen species. Chitosan is a biopolymer obtained by deacetylation of chitin with antioxidant and metal ion chelating properties. In this study, the protective effect of chitosan on arsenic-induced nephrotoxicity and oxidative damage was investigated. 32 male Wistar-albino rats were divided into 4 groups of 8 rats each as control group (C), chitosan group (CS group), arsenic group (AS group), and arsenic+chitosan group (AS+CS group). The C group was given distilled water by oral gavage, the AS group was given 100 ppm/day Na-arsenite ad libitum with drinking water, the CS group was given 200 mg/kg/day chitosan dissolved in saline by oral gavage, the AS+CS group was given 100 ppm/day Na-arsenite ad libitum with drinking water and 200 mg/kg/day chitosan dissolved in saline by oral gavage for 30 days. At the end of the 30-day experimental period, 90 mg/kg ketamine was administered intraperitoneally to all rats, and blood samples and kidney tissues were collected. Urea, uric acid, creatinine, P, Mg, K, Ca, Na, Cystatin C (CYS-C), Neutrophil Gelatinase Associated Lipocalin (NGAL) and Kidney Injury Molecule 1 (KIM-1) levels were measured in serum samples. Malondialdehyde (MDA), Glutathione (GSH), Catalase (CAT) and Superoxide dismutase (SOD) levels in the supernatant obtained from kidney tissue were analyzed by ELISA method. Compared with AS group, uric acid and creatinine levels of the AS+CS group were significantly decreased (p<0.001), urea, KIM-1, CYS-C, NGAL, and MDA levels were numerically decreased and CAT, GSH, and SOD levels were numerically increased (p>0.05). In conclusion, based on both biochemical and histopathological-immunohistochemical- immunofluorescence findings, it can be concluded that chitosan attenuates kidney injury and protects the kidney.

Effect of non-genetic factors on milk yields traits in Simmental cows raised subtropical climate condition / Efeito de fatores não genéticos em produção de leite em gado simmental criado em condições climáticas subtropicais

The aim of this study was to identify non-genetic parameters affecting the milk yield traits of Simmental cows raised in subtropical climate conditions. Records on 1904 lactation events of Simmental cows (N=706) during 2001-2014 were included in this study. A generalized linear model was used to investigate the effect of non-genetic factors (calving year, season, and age; lactation number; birth type; and calf sex) on real milk yield (MY), adjusted 305-d lactation milk yield (305-d MY), adjusted mature-age 305-d lactation milk yield (305-d MAMY), lactation length (LL), and dry periods (DP). The MY, 305-d MY, 305-d MAMY, LL, and DP were 6413.04kg, 6060.30kg, 6871.21 kg, 329.88d, and 57.67d, respectively, in Simmental cows. The effects of calving year, birth type, and calf sex on MY were significant (P<0.05). Calving year, calving age, birth type, and calf sex had significant effects on 305-d MY (P<0.05). The 305-d MAMY was significantly affected by calving year, birth type, and calf sex (P<0.05). In conclusion, based on the findings of the present study, the milk yield traits of Simmental cows raised at subtropical climate conditions with ideal feeding and management strategies was in accordance with world standards.(AU)

O objetivo desse estudo foi identificar parâmetros não genéticos afetando características de produção de leite em vacas Simmental criadas em condições climáticas subtropicais. Registros em 1904 eventos de lactação de vacas Simmental (N=706) de 2001 a 2014 foram incluídos nesse estudo. Um modelo linear generalizado foi utilizado para investigar o efeito de fatores não genéticos (ano, estação, e idade de parto; número de lactação; tipo de nascimento; sexo do bezerro) em produção real de leite (MY), produção ajustada 305-d (305-d MY), produção ajustada madura 305-d (305-d MAMY), duração de lactação (LL), e períodos secos (DP). MY, 305-d MY, 305-d MAMY, LL, e DP foram 6413.04kg, 6060.30kg, 6871.21kg, 329.88d e57.67d, respectivamente, em vacas Simmental. Os efeitos de ano de parto, tipo de parto e sexo do bezerro em MY foram significantes (P<0.05). O 305-d MAMY foi significativamente afetado por ano de parto, tipo de parto e sexo do bezerro (P<0.05). Conclui-se que, baseado nos achados do presente estudo, a produção de leite de vacas Simmental criadas em condições climáticas temperadas com alimentação e estratégias de manejo ideais estava de acordo com padrões mundiais.(AU)