Rodrigo Diana Navarro

Enzyme activities of tadpoles of bullfrogs fed diets containing different levels of crude protein

EnglishThis study was aimed to determine the digestive enzyme activity in bullfrog tadpoles, fed with commercial ration during 55 days, at the density of one tadpole per liter in 30 l boxes. After 18 days the levels of protein influenced the activity of amylase quadratically to the estimated 32% CP. The same trend was observed for the specific activity of amylase influenced by the level of 28% crude protein and the activity of trypsin that influenced by the level of 29% CP. There was no significant difference in lipase activity and specific lipase. At 26 days of the amylase enzyme activity and specific activity of amylase and trypsin decreased with increasing the percentage of protein. The enzyme lipase and lipase specific activity increased linearly to increased levels of protein. At 35 days of experiment amylase activity was statistically significant for treatment with 28% CP. The specific activity of amylase and trypsin activity decreased with increased protein in the diet. The activity of lipase at 35 and 55 days of the experiment increased significantly with increased protein in the diet. At 55 days of the experiment increased protein in the diet influenced in a linear activity of trypsin. The lipase activity and specific activity of lipase increased with increasing levels of dietary crude protein. portuguesEste estudo objetivou determinar a atividades das enzimas digestivas de girinos de ra-touro, alimentados com diferentes racoes durante 55 dias, na densidade de um girino por litro, em caixas com 30 l de agua em condicoes laboratoriais. Aos 18 dias os niveis de proteina influenciaram a atividade da amilase de forma quadratica ate o valor estimado 32% PB. A mesma tendencia foi observada para a atividade especifica da amilase que influenciou ate o nivel de 28% de PB e da atividade da tripsina que influenciou ate o nivel de 29% de PB. Nao foi observada diferenca signifi- cativa para lipase e atividade especifica da lipase. Aos 26 dias a atividade enzimatica da amilase e atividade especifica da amilase e da Tripsina diminuiu com aumento da porcentagem de protei- na. A enzima lipase atividade especifica da lipase aumentaram de forma linear ao aumento dos niveis de proteina. Aos 35 dias de experimento a atividade da amilase foi estatisticamente significativa para o tratamento com 28% de PB. A atividade especi- fica da amilase e a atividade da tripsina diminuiram com aumento da proteina na racao. Ja a atividade da lipase aos 35 e 55 dias de experimento aumentou significativamente com aumento da proteina na racao. Aos 55 dias de experimento o aumento da proteina na racao influenciou de forma linear a atividade da tripsina. A atividade da lipase e atividade especifica da lipase aumentaram com a elevacao do nivel de proteina bruta na racao.

Desempenho produtivo de tambacus alimentados com dietas suplementadas com vitamina E

The objective of this work was to evaluate the effects of tambacu vitamin E dietary supplementation on performance and hematological variables, and determine the relationship of glutathione peroxidase activity with vitamin E and selenium suplementation. Two hundred and fifty juvenile tambacus were used, divided into 25 aquaria. The basal diet was pelleted with 32% of crude protein and 3,300 kcal kg-1 of digestible energy, with 0.40 mg kg-1 Se. Test diets - isoproteic and isocaloric - were composed of the basal diet with increasing vitamin E concentrations (0, 100, 200, 300, 400 mg kg-1), in a completely randomized design, with five treatments and five replications. No significant effect of vitamin E supplementation was observed on total length, mean corpuscular volume, mean corpuscular hemoglobin concentration and total erythrocyte, and on the enzymatic activity of glutathione peroxidase. However, final weight and apparent feed conversion were significantly affected by supplemented treatments. Standard length and weight gain improved using diets supplemented with 400 mg kg-1 of vitamin E. Dietary vitamin E supplementation results in better tambacu performance.

Effect of photoperiod stress assessment and locomotor activity of female lambari (Astyanax bimaculatu)

Some studies and scientific investments have been done in aquaculture aiming to minimize the stress of the fish due to different factors, as management, nutritional status, water quality, temperature, photoperiod, and salinity. This study aimed to verify the effect of photoperiod on locomotor activity and plasma levels of cortisol and glucose in female Lambari. One hundred and twenty female Lambari adult were maintained in aquaria of 20 liters each in a completely randomized design with three treatments (T1 = 0Light: 24Dark, T2 = 12L: 12D, T3 = 24L: 0D) and four replications. The daily locomotor activity was registered during 15 days using an infrared photocell. After 40 days of experiment and previous fasting for 24 hours, fish were euthanized by a lethal dose of benzocaine. Female Lambari featured a diurnal rhythm of locomotor activity. Lambari subjected to 12:12 and LD photoperiod presented higher cortisol (12L:12E: 190.00 ± 37.73 ng/mL e 24L:0E: 148.850 ± 32.77 ng/mL) and locomotor activity levels and also lower survival rates (30.0 ± 7.07%) when compared to the LD photoperiod (cortisol: 85.570 ± 7.99 ng/mL, survival rates: 72.5 ± 4.330%). The glucose concentration (32.167 ± 22.73 mg/dL) and the growth (7.050 ±0.59cm) of fish subjected to LD photoperiod was significantly lower than in the other treatments. We conclude that light plays an important role in the growth, behavior and welfare of female Lambari. Besides, our data highlighted that fish submitted to a long light period present a more stressed and more aggressive status when compared to fish submitted to a continuous darkness.

Desempenho zootécnico de girinos de rã-touro com diferentes níveis de proteína e energia digestíveis

From the digestibility values of some ingredients, it was proposed diets with different levels of digestible protein and energy, in a 3x3 factorial design for bullfrog tadpoles, aiming at evaluate the zootechnical performance. The experiment was conducted during 60 days with 810 tadpoles from the same spawning distributed into 27 polypropylene boxes at a density of 1 tadpole/L. The experimental design consisted of a factorial arrangement with three levels of digestible protein (27; 31 and 35%) and three levels of digestible energy (2700; 2800 and 2900kcal/kg) with three repetitions. Parameters evaluated at 60 days were weight gain, feed intake, dietary protein intake, feed conversion, protein efficiency rate and survival rate. Results were subjected to analysis of variance and Duncan test (95% accuracy), and presented no interaction between digestible protein and digestible energy for any parameter evaluated. As for the digestible protein, significant differences were detected in the dietary protein intake, and protein efficiency rate, evidencing inefficiency of diets with high protein values. Bullfrog tadpoles should be given diets with 27% digestible protein by having the best result for the protein efficiency rate and for the dietary protein intake, with the lowest value and similar to other levels among evaluated parameters.

Parâmetros hematológicos de tilápias-do-Nilo (Oreochromis niloticus) alimentadas com diferentes fontes de óleo

Objetivou-se avaliar a influencia das fontes de oleo da dieta sobre os parâmetros hematologicos de tilapias do Nilo (Oreochromis niloticus). Foram utilizados 112 juvenis, com peso medio inicial de 50±12g, distribuidos em 16 caixas com capacidade total de 100L cada, num delineamento inteiramente casualizado com quatro tratamentos e quatro repeticoes, contendo sete peixes por repeticao. Os tratamentos eram constituidos por: tratamento um – oleo de soja; tratamento dois – oleo de peixe; tratamento tres – oleo de linhaca; tratamento quatro – oleo de oliva. As racoes eram semipurificadas, isoproteicas (32% de proteina bruta) e isocaloricas (3200 kcal de energia bruta/kg de racao). Nao houve diferenca (P>0,05) entre os tratamentos quanto ao numero e diferenciacao de leucocitos, numero de eritrocitos totais e niveis de hemoglobina. Os peixes do tratamento um apresentaram niveis superiores de hematocrito (P<0,05) comparados aos tratamentos dois e tres. Encontrou-se maior volume corpuscular medio (VCM) nos peixes do tratamento quatro em relacao aos outros tratamentos (P<0,05). O tratamento tres apresentou concentracao de hemoglobina corpuscular media (CHCM) superior, comparado aos peixes do tratamento quatro (P<0,05). As fontes de acidos graxos da dieta podem influenciar os parâmetros hematologicos de tilapia do Nilo (Oreochromis niloticus). Houve uma tendencia de aumento na eritropoiese de tilapia do Nilo alimentadas com dietas contendo altos niveis de acidos graxos da serie ω-6. As fontes dieteticas de oleo testadas nao foram capazes de alterar o numero total de eritrocitos e celulas sanguineas da serie branca em tilapias do Nilo.

Plasma levels of luteinizing hormone and gonadal maturation of lambari females under different photoperiods

The objective of this work was to evaluate the effect of photoperiod on luteinizing hormone (LH) plasma levels and gonadal maturation of lambari females. One hundred and twenty adult lambaris, distributed into 12 aquaria of 20 L each, were randomly subjected to three different treatments, in a completely randomized design, and four replicates. Treatments were photoperiods in hours of light (L) and darkness (D): T1, 0 L:24 D; T2, 12 L:12 D; T3, 24 L:0 D. After 40 days, fish were subjected to fasting for 24 hours and, then, anesthetized. Immediately after slaughter, fish were weighed, and their gonads and livers were removed and weighed. Ovaries were weighed and immersed in Bouins fixative solution for 24 hours and, then, kept in 70% alcohol until processing the material. Subsequently, the oocyte developmental stage was determined. No significant differences were observed between treatments for final weight, ovary weight, gonadosomatic index (GSI), hepatosomatic index (HSI) and LH levels. In all treatments, lambari females showed maturing ovaries with prevalence of vitellogenic oocytes. Photoperiod does not affect the LH levels and ovarian maturation in lambari females.

Interação com os pais e o uso do espaço por um infante de Alouatta fusca (Geoffroy Saint-Hilaire, 1812) em cativeiro

Primates are social animals that have bond between mother and offspring, unlike other orders of mammals. The survival of an infant primate is completely dependent on the care provided by members of their social group, particularly maternal care. The aim of this study was to analyze the use of premises for an infant of monkey and its proximity to the parents. The group of monkeys was composed of a pair of adult female and her pup at 4 months of age. The observation period was from august to december 2006, making an average of 96 hours of sampling effort. The method of observation was the focal animal with instant record, with 30 second intervals for 1 hour per day. The study site was an exhibition space of the Zoo-Botanical Foundation of Belo Horizonte, 7 m high, 6 m wide, 7 m deep with the presence of internal landscaping. The results revealed greater contact with the infants mother and father in relation to a significant departure (P < 0.05) compared to the puppys maternal contact with increasing age and greater independence. The most used during the first 3 months of captivity was the pergola. In December, a period of higher rainfall, the chick ventral increased interactions with the mother, and stayed longer in the barrel. Information obtained here will contribute to a better understanding in relation to infants of Alouatta fusca, their social interactions and use of space that can be used to improve the ex-situ management of animals, creating better conditions for the stay of those in captivity, using appropriate structures that mimic the natural environment, to ensure the welfare of apes and thus the survival of the species.

Importância da vitamina C no crescimento e desenvolvimento gonadal em peixes

O crescimento saudavel dos peixes bem como, a melhora nos indices reprodutivos, e alcancado com o balanceamento de dietas em funcao da exigencia nutricional em cada fase de desenvolvimento. A vitamina C atua em diversos processos fisiologicos no peixe, sendo, portanto, de suma importância o conhecimento dos seus efeitos no organismo do animal. O presente trabalho aborda os efeitos da vitamina C no crescimento e no desenvolvimento gonadal dos peixes.