Effects of different general anesthetics on serum hemolysis and hepatic and muscular glycogenolysis in rats

Anesthetics can affect the structure and biological function of tissues and systems differentially. The aim of the present study was to compare three injectable anesthetics generally used in experiments with animals in terms of the degree of hemolysis and glycogenolysis occurring after profound anesthesia. Twenty-four male Wistar rats (330-440 g) were divided into three groups (N = 8): chloral hydrate (CH), ketamine + xylazine (KX), Zoletil 50® (zolazepam and tiletamine) + xylazine (ZTX). After deep anesthesia, total blood was collected. The liver and white (WG) and red gastrocnemius (RG) muscles were also immediately removed. The degree of serum hemolysis was quantified on the basis of hemoglobin concentration (g/L). Hepatic and muscular glycogen concentrations (mmol/kg wet tissue) were quantified by the phenol-sulfuric method. The CH and KX groups exhibited serum hemolysis (4.0 ± 2.2 and 1.9 ± 0.9 g/L, respectively; P < 0.05) compared to the ZTX group, which presented none. Only KX induced elevated glycogenolysis (mmol/kg wet tissue) in the liver (86.9 ± 63.2) and in WG (18.7 ± 9.0) and RG (15.2 ± 7.2; P < 0.05). The CH and ZTX groups exhibited no glycogenolysis in the liver (164.4 ± 41.1 and 176.8 ± 54.4, respectively), WG (28.8 ± 4.4, 32.0 ± 6.5, respectively) or RG (29.0 ± 4.9; 25.3 ± 8.6, respectively). Our data indicate that ZTX seems to be an appropriate general anesthetic for studies that seek to simultaneously quantify the concentration of glycogen and serum biochemical markers without interferences. ZTX is reasonably priced, found easily at veterinary markets, quickly induces deep anesthesia, and presents a low mortality rate.

Digestibilidade dos nutrientes do bagaço de mandioca em dietas de novilhas leiteiras / Digestibility of nutrients of cassava bagasse in diets of milk heifers

Avaliou-se o efeito da inclusão de quatro proporções, 0, 7, 14 e 21 por cento, de bagaço de mandioca na digestibilidade aparente dos nutrientes em 20 novilhas leiteiras, ¾Gir x »Holandês, com peso corporal médio inicial de 180kg. Os animais foram distribuídos em delineamento inteiramente ao acaso e receberam dietas compostas por silagem de sorgo como volumoso. Avaliaram-se os coeficientes de digestibilidade (CD) aparente de matéria seca (MS), matéria orgânica (MO), proteína bruta (PB), extrato etéreo (EE), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA), carboidratos não-fibrosos (CNF) e determinaram-se os nutrientes digestíveis totais (NDT) das dietas. Os CD de MS, MO, PB e FDA não foram afetados pelos tratamentos. Os CD do EE foram de 80,9; 73,2; 74,7 e 68,3 por cento; da FDN de 55,0; 48,3; 49,1 e 37,4 por cento e do CNF de 87,9; 89,5; 84,6 e 83,1 por cento para as proporções de 0, 7, 14 e 21 por cento, respectivamente. O teor de NDT das dietas teve redução linear quando se elevou a proporção de bagaço na dieta, apresentando valores de 68,0; 66,2; 67,0 e 62,5 por cento para os tratamentos com 0, 7, 14 e 21 por cento, respectivamente. Recomenda-se a de inclusão de bagaço de mandioca na dieta de novilhas leiteiras em até 14 por cento.

The inclusion of 0, 7, 14, and 21 percent of cassava bagasse was evaluated on apparent digestibility of nutrients in dairy heifers. Twenty ¾Gir x »Holstein dairy heifers averaging 180kg initial mean body were used. The animals were distributed in a completely randomized design and received diets composed by sorghum silage as roughage. The apparent digestibility coefficients (DC) of dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), neutral detergent fiber (NDF), acid detergent fiber (ADF), and non-fiber carbohydrates (NFC) were evaluated and total digestible nutrients of diets (TDN), were determined. DM, OM, CP, and ADF digestibility coefficients were not affected by treatments. DC of the EE were 80.9, 73.2, 74.7, and 68.3 percent; for NDF 55.0, 48.3, 49.1, and 37.4 percent and for NFC of the 87.9, 89.5, 84.6, and 83.1 percent for 0, 7, 14, and 21 percent treatments, respectively. TDN content had linear reduction as diet cassava bagasse level increased, showing values of 68.0, 66.2, 67.0, and 62.5 percent for 0, 7, 14, and 21 percent treatments, respectively. It is recommended the inclusion of cassava bagasse for dairy heifers diet until 14 percent.