Toxicological comparison of Crotalus ruber lucasensis venom from different ecoregions of the Baja California Peninsula.

The Baja California Peninsula possesses a mosaic of ecoregions that offers a wide variety of environments for the species that here inhabit. Here we report biological variations in. Crotalus ruber lucasensis venom from arid, semiarid and tropical eco-regions. Lethal (1.4-6.8 mg/kg), edematogenic (0.3-0.5 µg) and defibrinogenating (from non-detectable to 20 µg) activities were found to have significant differences among eco-regions.

Comparison of biological and biochemical characteristics of venom from rattlesnakes in the southern Baja California Peninsula.

In Mexico more than 40% of reported snakebites are due to rattlesnake species. In general, the venoms of these snakes are characterized by the presence of highly enzymatic components that could provoke coagulopathies, local and systemic tissue damage and some cases neurotoxicity. In northwestern Mexico (Baja California Peninsula, Gulf of California and Pacific islands), 15 species of Crotalus are distributed. Such a biodiversity implies a high variability in venom compositions that in turns would results in high variability in clinical manifestations. In this work, venoms of Crotalus catalinensis, C. enyo enyo, C. mitchellii mitchellii and C. ruber lucasensis were studied. Lethal doses from 0.35 to 9.21 mg/kg were obtained being venom of C. m. mitchellii the most potent of all. Venoms of C. catalinensis, C. e. enyo and C. r. lucasensis show high hemorrhagic potency (1.34, 1.48 and 1.68 µg respectively). Coagulant activity was found in venoms of C. catalinensis (4.6 µg), C. e. enyo (101.9 µg) and C. m. mitchellii (13.6 µg). Our results point out hemorrhage as one of the most expected signs by three of the four most abundant species in the area. Also, neurotoxicity must be expected by C. m. mitchellii.

Ciguatera in Mexico (1984⁻2013).

Historical records of ciguatera in Mexico date back to 1862. This review, including references and epidemiological reports, documents 464 cases during 25 events from 1984 to 2013: 240 (51.72%) in Baja California Sur, 163 (35.12%) in Quintana Roo, 45 (9.69%) in Yucatan, and 16 (3.44%) cases of Mexican tourists intoxicated in Cuba. Carnivorous fish, such as snapper (Lutjanus) and grouper (Epinephelus and Mycteroperca) in the Pacific Ocean, and great barracuda (Sphyraena barracuda) and snapper (Lutjanus) in the Atlantic (Gulf of Mexico and Caribbean Sea), were involved in all cases. In the Mexican Caribbean, a sub-record of ciguatera cases that occurred before 1984 exists. However, the number of intoxications has increased in recent years, and this food poisoning is poorly studied in the region. Current records suggest that ciguatera fish poisoning in humans is the second most prevalent form of seafood poisoning in Mexico, only exceeded by paralytic shellfish poisoning (505 cases, 21 fatalities in the same 34-year period). In this study, the status of ciguatera in Mexico (epidemiological and treatment), and the fish vectors are reviewed. Dinoflagellate species Gambierdiscus, Ostreopsis, and Prorocentrum are related with the reported outbreaks, marine toxins, ecological risk, and the potential toxicological impact.

First Record of Fibropapillomatosis in a Green Turtle Chelonia mydas from the Baja California Peninsula.

Fibropapillomatosis (FP) is characterized by multiple fibroepithelial tumors in all parts of the skin and has been reported in sea turtles worldwide. Clinically infected individuals are often emaciated and anemic. In Mexico, however, there are few records of this disease. In this study of green turtles Chelonia mydas in Laguna San Ignacio in Baja California Sur (BCS), we noted one juvenile with multifocal fibropapilloma lesions on the external upper surface of its eyes and hind flippers. Light microscopy revealed hyperkeratosis, epidermal hyperplasia, dermal papillary projections, and fibroblast proliferation. Electron microscopy revealed viral particles. Biopsies of normal skin were done to determine the origin of the turtle through genetic analysis. Its mitochondrial DNA matched that of a haplotype (CMP2) from a Hawaiian green turtle population. Finding FP in a turtle captured in BCS elucidates the need for further monitoring along the west coast of Mexico. Further investigation should include testing tumors to detect and characterize any chelonid herpesviruses and explore any association with FP and other diseases that pose a health risk to other sea turtle species. Received March 26, 2016; accepted August 3, 2016.