Introduction

Boid snakes fits in captivity when their basic needs like feeding, health, humidity e temperature are met, and also for his gentleness and ease handling (Fowler et al. 2001). Snakes ex-situ maintenance to didactic and/or scientific purpose becomes necessary as studies about these reptiles occur. Fact's triviality doesn't make prophylactic care irrelevant, because animals become depleted, as a result of adverse conditions presented by life in captivity; which is different from those found in wild life (Iizuka 1984). However, there are many cases where some preventive actions taken are inadequate to ensure snakes health, and so they start to suffer numerous opportunistic infections and infestations (Hoge 1981). As ectothermic animals, snakes have hematological values varying with temperature, so the season is an important influence factor. Hemogram is a fast option to measure blood cellular elements and if presented changes is or not related to inflammatory disease, especially parasitic and microbial (Thrall et al. 2007). Leukocytes percentage in differential count varies with the species, being influenced also by stress. So, normal hematological values knowledge of some species is important to clarify a lot of diseases diagnosis in these animals, both kept in captivity or kept in wild life (Greek et al 2006; Thrall et al. 2007). Hematological studies in reptiles are scarce, and just a few studies have been conducted (Greek et al. 2006). In Pará State, Brazil, this is the first research studying seasonality influence in the hematological parameters of Snakes kept in captivity.

Materials and Methods

This research was authorized by IBAMA (Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis) to be performed. 26 adult Boa constrictor sp, both sexes (17 males and nine females), maintained in captivity in Museu Paraense Emílio Goeldi, Belém, Pará State, Brazil, and Commercial farm "Xerimbabo" in Santo Antônio do Tauá, Pará State, Brazil. Blood samples were collected by cardiocentesis, approximately 2mL, and samples included in heparinized tubes. Blood smears were made immediately after collection. Red blood cell (RBC) and white blood cell (WBC) counts were determined by Natt-Herrick method using a Neubauer chamber. The packet cell volume (PCV) was determined by the microhematocrit method and the hemoglobin was measured by spectrophotometry. The differential leukocyte counts and thrombocytes count were performed on smears stained by the rapid staining hematological method "Panótico". Were also determined the erythrocytes indices MCV and MCHC.

Results

The results were processed in Spreadsheets Excel (version 2007) and it was determined the arithmetic mean and standard deviation of the values found, with respective ranges of variation. 61.53% were male and 38.47% females and was determined to erythrocytes, 629.23 ± 275.06 x 10⁶/mm³; 8.95 ± 2.57 g / dL for hemoglobin (Hb) 27.84 ± 7.17% for hematocrit (Ht); 51.69 ± 23.87 fL to mean corpuscular volume (MCV), 32.50 ± 7.90 for mean corpuscular hemoglobin concentration (MCHC), 5.41 ± 0.29 g / dL for total plasmatic protein (PPT) and 18.07 ± 10.77 x 10³/mm³ to total leukocytes. In calculating differential, it was determined to figures 6908 + 5932.13 (/μl) for lymphocytes; 2834.42 + 2047.75 (/μl) for heterophils; 8277.30 + 6397.25 (/μl) for azurophilic monocytes.

Table 1. Hematological values (mean, standard deviation and range of variation) for boid snakes kept in captivity in Amazon Region. 2009.

N = total sample

Table 2. Hematological values (mean, standard deviation and range of variation) for males of the boid snakes kept in captivity in Amazon Region. 2009.

N = total sample

Table 3. Hematological values (mean, standard deviation and range of variation) for females of the boid snakes kept in captivity in Amazon Region. 2009.

N = total sample

Discussion and Conclusions

According Thrall et al. 2007, snakes have significant changes in their hematologic values influenced by a lot of factors, such as seasonality, object of this research. In winter, for example, leukocytes and erythrocytes numbers are generally lower compared to mammals and birds, so, these animals became more susceptible to various diseases. The Amazon region has a peculiarity that is a dry period, called "Amazon summer" and a rainy season called "Amazon winter". Erythrocyte, hematocrit, hemoglobin and total leukocytes values were higher when compared to the summer values of Machado et al. 2006. This variation may be related to high temperature in the region during the dry period, remembering that pets are ectothermic and has its metabolism changed by temperature, which emphasizes the importance of this research. Erythrocyte indexes MCV, MCHC, in addition to the total plasmatic protein, were determined, but there's no specialized literature description of this parameters values for this species. Cellular classification in monocytes or azurophiles, is very is very controversial. In this research, this cell type was classified as azurophilic monocytes, different from that proposed by Machado et al. 2006. Most hematological values found in females are greater than that in males, but is not described in the literature any relationship of these values regarding sex. We can conclude that these parameters serve as reference for the species studied kept in captivity in Amazon region, until further studies using larger number of animals and a longer period of study, be done.

References

1.  Fowler ME, Cubas ZS. Biology, Medicine and Surgery of South American Wild Animals. Iowa: Iowa State University Press, 2001.

2.  Iizuka H, et al. Estomatite ulcerativa infecciosa em Boa constrictor constrictor mantidas em cativeiro. Memórias do Instituto Butantan, v. 47/48, 1983/84, p.113-120.

3.  Hoge AR, Federsoni PA. Manutenção de Serpentes em Cativeiro. Biotério, v.1, p.63-73, 1981.

4.  Grego KF, Alves JAS, Rameh de Albuquerque LC, Fernandes W. ReferÍncias hematológicas para a jararaca de rabo branco (Bothrops leucurus) recém capturadas da natureza. Arq. Bras. Med. Vet. Zootec., v.58, n.6, p.1240-1243, 2006.

5.  Thrall MA. Hematologia e bioquímica clínica veterinária. São Paulo: Roca, 2007.

6.  Machado CC, Silva LFN, Ramos PRR, Takahira DVM. Seasonal influence on hematologic values and hemoglobin electrophoresis in Brazilian Boa constrictor amarali. Journal of Zoo and Wildlife Medicine, 2006.