We found evidence of the presence of anticoagulant resistant M. musculus L. in the study area. Feeding behaviour may have contributed to increasing the time of survival, and may be a mechanism that allows metabolic clearance of the bromadiolone. Under field conditions control with anticoagulants would be less effective because animals have alternative food.

The main goal of the paper was to determine the habitat distribution of the house mouse (Mus musculus) within a rural landscape of Buenos Aires province, Argentina. We also studied the seasonal variation in abundance and reproductive activity. The habitats studied were poultry farms, human houses in a small village, cropfields, pastures, cropfield and pasture edges, riparian habitats (streams), railway embankments and woodlots. We captured 817 M. musculus and 690 individuals of 5 native rodent species. M. musculus was captured in poultry farms, houses, riparian habitats, cropfield and borders, but it showed a significantly higher abundance in poultry farms compared to the other habitats. Its presence outside poultry farms was significantly related to the distance to streams and poultry farms. The mean trapping success index of M. musculus did not show significant variations between periods, but the proportion of active males was significantly higher in the spring-summer period than in the autumn-winter period. All captures of M. musculus in cropfields, borders and riparian habitats occurred in the spring-summer period. The capture of M. musculus in many types of habitats suggests that it can disperse outside poultry farms, and streams may be used as corridors.

Objective(s): The hamster carcinogenesis model recapitulates oral oncogenesis.Dimethylbenz [a]anthracene (DMBA) cancerization induces early severe mucositis, affecting animal´s welfare and causing tissue loss and pouch shortening. "Short" pouches cannot be everted for local irradiation for Boron Neutron Capture Therapy (BNCT). Our aim was to optimize the DMBA classical cancerization protocol to avoid severe mucositis, without affecting tumor development. We evaluated BNCT in animals cancerized with this novel protocol. Materials and Methods: We studied: Classical cancerization protocol (24 applications); Classical with two interruptions (completed at the end of the cancerization protocol). BNCT mediated by boronophenylalanine (BPA) was performed in both groups. Results: The twice-interrupted group exhibited a significantly lower percentage of animals with severe mucositis vs the non-interrupted group (17% vs 71%) and a significantly higher incidence of long pouches (100% vs 53%). Tumor development and the histologic characteristics of tumor and precancerous tissue were not affected by the interruptions. For both groups, overall tumor response was more than 80%, with a similar incidence of BNCT-induced severe mucositis. Conclusion(s): The twice-interrupted protocol reduced severe mucositis during cancerization without affecting tumor development. This favoured the animal's welfare and reduced the number of animals to be cancerized for our studies, without affecting BNCT response.

Background: BNCT (Boron Neutron Capture Therapy) is a tumor-selective particle radiotherapy that combines preferential boron accumulation in tumors and neutron irradiation. Although p-boronophenylalanine (BPA) has been clinically used, new boron compounds are needed for the advancement of BNCT. Based on previous studies in colon tumor-bearing mice, in this study, we evaluated MID:BSA (maleimide-functionalized closo-dodecaborate conjugated to bovine serum albumin) biodistribution and MID:BSA/BNCT therapeutic effect on tumors and associated radiotoxicity in the hamster cheek pouch oral cancer model. Methods: Biodistribution studies were performed at 30 mg B/kg and 15 mg B/kg (12 h and 19 h post-administration). MID:BSA/BNCT (15 mg B/kg, 19 h) was performed at three different absorbed doses to precancerous tissue. Results: MID:BSA 30 mg B/kg protocol induced high BSA toxicity. MID:BSA 15 mg B/kg injected at a slow rate was well-tolerated and reached therapeutically useful boron concentration values in the tumor and tumor/normal tissue ratios. The 19 h protocol exhibited significantly lower boron concentration values in blood. MID:BSA/BNCT exhibited a significant tumor response vs. the control group with no significant radiotoxicity. Conclusions: MID:BSA/BNCT would be therapeutically useful to treat oral cancer. BSA toxicity is a consideration when injecting a compound conjugated to BSA and depends on the animal model studied.

Geoffroy's cat (Leopardus geoffroyi), a small wild cat of South America, showed in the last years a decline in population abundance mainly related to both habitat destruction and hunting. The increasing human population densities and the consequent demand for food and natural resources will rapidly erode and fragment its remaining habitats. In Argentina most studies about Geoffroy's cat diet have been conducted in protected areas or in their surroundings, while there are no studies conducted in purely agricultural systems. We described the diet composition of Leopardus geoffroyi and its seasonal variations in an agricultural ecosystem to contribute knowledge of its ecology and natural history. The study was carried out from spring 2008 to spring 2011. A total of 494 scats were analyzed and at least 695 prey-items were identified. The diet included 81.58% of mammal prey, representing 93.32% of the potential biomass ingested. Within mammals, the principal prey were rodents, representing 79.57% of the total prey items and 59.39% of the total potential biomass consumed. Small rodents account for a great proportion of prey items, while larger species, as the caviid Cavia aperea, contributed more biomass. The diet plasticity may enhance the persistence of Geoffroy's cat populations in variable and anthropized ecosystems.

No abstract

This study aimed to analyze the role of Mus musculus as a host of Leptospira spp., lymphocytic choriomeningitis virus (LCMV) and Toxoplasma gondii , in poultry farms of Buenos Aires province, Argentina, and to assess the potential risk of transmission to humans and domestic or breeding animals. Samplings were performed between 2009 and 2011 (S1) and during 2016 (S2). In S1, we studied the prevalence of infection for Leptospira spp. and LCMV, whereas, in S2, we studied the prevalence of infection for Leptospira spp. and T. gondii. In S1, we found an overall Leptospira spp. prevalence in M. musculus of 18% (14/79) and no positive serum samples for LCMV (0/166). In S2, we detected no positive individuals for Leptospira spp. (0/56) and an overall T. gondii seroprevalence of 3.6% (2/56). The probability of Leptospira spp. infection in M. musculus was higher in reproductively active individuals and in samplings subsequent to months with high accumulated precipitation. Our results suggest that, in the poultry farms studied, the presence of M. musculus may be a risk factor in the transmission of Leptospira spp. and T. gondii to humans and domestic animals. The management of farms should include biosecurity measures for farm workers and more effective rodent control.

Our aim was to assess the effect of environmental factors on short temporal abundance variations of the two most abundant native rodents of agricultural agroecosystems, Akodon azarae and Calomys laucha. We conducted a 3-year longitudinal sampling of rodents, and recorded meteorological data such as temperature and precipitation, predation rate by Leopardus geoffroyi, Tyto furcata and Athene cunicularia, vegetation cover and height, characteristics of cropfields and their borders. The effect of these factors on rodent abundance was evaluated through generalized linear mixed models. Abundance variations of both rodent species were explained by characteristics of both cropfields and their borders. At the studied temporal scale, meteorological variables did not have a direct effect on abundance variations, but probably influenced through vegetation characteristics and were expressed in seasonal variations. For A. azarae there was also an effect of predation by L. geoffroyi (positive) and T. furcata (negative), while predation by A. cunicularia did not contribute to explain abundance variations of any species.