Status and Conservation of Crocodylus acutus at a Naval Base in Aragua State, Venezuela

We present the conservation status and ecological characteristics (distribution, habitat preference, reproduction, population size, and structure) of an American Crocodile (Crocodylus acutus) population associated with the naval base "TN Tomas Vega" in Turiamo Bay, Aragua state, Venezuela. The sheltered coastal habitats, with freshwater or brackish water, as San Miguel River of Turiamo Bay, provide essential nursery habitats for hatchling American Crocodiles. During the breeding season, we looked for signs of nesting activity; however, because of continuous military exercises in the area, it is currently not known where nesting occurs. Based upon spotlight surveys of 6.7 km of survey routes, the resident American Crocodile population of Turiamo Bay was estimated at 38 American Crocodiles. Of this population, 6 sightings were classified as eyeshine only, 11 as class I, 14 as class II, 6 as class III, and 1 as class IV, exhibiting differential habitat association according to the size class. Encounter rates were highest in the brackish lagoon and low in the west coast and the San Miguel River, possibly because of the activities of the naval base causing evasive behavior by American Crocodiles. Our results indicate the C. acutus population in Turiamo Bay has been relatively stable in the past few years. However, it is important to accurately estimate the population size of C. acutus and protect the nesting and nursery habitats. Therefore, we recommend continuation of the population studies and involvement of environmental organizations to regulate anthropogenic activities in Turiamo Bay.Fil: Hilevski Loreto, Samuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Velasco, Alvaro. Fauna Silvestre Productos y Servicios; Venezuel

A novel laxative method for crocodilians and digestibility of soybean (Glicine max) in broad-snouted caiman (Caiman latirostris)

The objectives of this study were to evaluate the laxative capacity of saline solution, vegetable oil, and a commercial drug on Caiman latirostris and determine digestibility of diets with plant derived protein sources as a supplement for this species. After a trial using three laxative treatments in different doses, caimans were treated with 1.5 mL of lactulose daily for two days. They were then force-fed their corresponding diet once per day for 7 days and then digesta residues were collected. Digestibility was determined through a dietary marker, acid digestion of digesta residues, and calculated with a standard equation. Digestion of diets were between 96 and 99%, exhibiting differences among these (P = 0.0006), with the control diet 2.45% lower than treatments diets (P = 0.0050). Digestibility of soybean meal was between 90 and 95%. There were differences according to the treatment diet (P = 0.018). The results of this study indicate that the use of lactulose as a laxative for C. latirostris is effective and does not affect health. Inclusion of soybean meal in the diet of C. latirostris at levels of 20–60% improved its digestibility and nutrients were efficiently digested. Deliberate ingestion of plant material by wild crocodilians may serve to aid digestion and absorption of dietary nutrients, and not act only as gastroliths. This information could be used to develop crocodilian diets and assist future research to determine optimum nutrient levels and ingredient combinations for farm-raised crocodilians fed compounded diets.Fil: Hilevski Loreto, Samuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Siroski, Pablo Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; Argentin

Captive breeding of Crocodylus intermedius (Graves, 1819) under different stocking densities

Crocodylus intermedius is restricted to the Orinoco River basins in Colombia and Venezuela. It is also one of the most endangered New World crocodilians. To determine the optimal density of individuals and the number of refuges to improve the rearing conditions of C. intermedius this study used 228 captive-reared crocodiles that were split in three individual densities and housed in concrete tanks. They were fed five days per week and measured at one, six, and eleven months of age. These data were used to calculate body condition index (BCI), weight, and length gain of each individual. Our results indicated that animals of groups group B (1.82 m2/individuals) were longer than animals of groups A (0.71 m2/individuals) and C (0.54 m2/individuals). While animals of groups A and C were less heavy than animals of group B, indicating that the density of C. intermedius is inversely correlated with their growth like in other crocodilian species. Whit respect to the BCI, group B had greater BCI than group A and C. This confirms the Orinoco crocodiles have a better development at relatively low densities. Through to the BCI we can be conclude that adding a second refuge only beneficial at “low” densities (associated with higher food conversion rates), whereas at “high” densities adverse effects on weight and length gain. To C. intermedius use of a second refuge and select a density that let rearing a major number of individuals and promoting a fast growth rate is beneficial for both conservation and commercial perspectives.Fil: Ortega, Saul. Universidad de Carabobo.; VenezuelaFil: Hilevski Loreto, Samuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Hernandez, Omar. Fundación para el Desarrollo de las Ciencias Físicas Matemáticas y Naturales; Venezuel

Relationship between skin colour, conjunctivitis, and dermatitis in captive Caiman latirostris in Argentina

The commercial production of crocodilians for skin and meat has been considered an important industry in the world, with skin being the most valuable product, while the meat is considered a by-product. This study was designed to identify some diseases that can affect crocodilians farmed in Argentina, examining the relationships between skin colour and these diseases. Each caiman was classified according to their skin colour and kind of diseases (conjunctivitis or dermatitis). In broad-snouted caimans the prevalence of conjunctivitis was 0.41, and dermatitis was 0.23. Statistical tests indicate that there may be a relationship between the skin colour and health status of the caiman, where the dark–skin animals appear healthier (35.76%) than the light–skin animals (15.89%), where these last are more vulnerable to suffer ocular diseases, and skin diseases at the same time (14.57%). In addition, the body mass and length of healthy animals (dark and light) were higher than caimans with eye disease or with both associated diseases. These results may help crocodilians farms caring by isolation of susceptible animals, establishing stricter criteria for health status. This may imply a decrease in diseases that affect the quality of the skin and the loss of individuals, with a consequent increase in profits obtained by the industry.Fil: Hilevski Loreto, Samuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Ciocan, Hernán. Universidad Nacional del Litoral. Facultad de Humanidades y Ciencias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bassetti, Luís Antonio Bochetti. Universidade de Sao Paulo; BrasilFil: Siroski, Pablo Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; Argentin

Blood biochemistry parameters of Broad snouted caiman, Caiman latirostris subjected to stress conditions, appliying micro-volume techniques

Plasma biochemistry values represent a crucial and minimally invasive tool for evaluating nutritional and physiological condition of the animal. Biochemical data provides valuable information in those species exposed to environmental stressors. In this study, we aimed to apply for the first time micro-volume plasma tests to measured total plasma protein, albumin, and glucose in juvenile Caiman latirostris and to compare our results with other studies reporting crocodilian biochemistry values. We found that caimans from heat treatment were heavier, longer and had higher levels of glucose than those from the control group. Conversely, food restricted caimans had less growth, body condition and had 32.1% lower albumin concentrations than those from the control group. While no significant differences were observed in any parameters measured from water restricted caimans compared with control group. The values obtained for each of the biochemical determinations were lower than those previously reported for adult of C. latirostris, but similar finding for protein concentration compared with Alligator mississippiensis. Micro technique offers the advantage of increasing information and at the same time a greater physiological understanding of the crocodilians species.Fil: Moleón Bersani, María Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Santiago, Gonzalo. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Santa Fe. Instituto de Investigacion de la Cadena Lactea. - Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Santa Fe. Estacion Experimental Agropecuaria Rafaela. Instituto de Investigacion de la Cadena Lactea.; ArgentinaFil: Hilevski Loreto, Samuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Siroski, Pablo Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; Argentin