Understanding the winter distributions of migrant birds is important because productivity and recruitment are influenced by conditions at several locations and periods in the life cycle of individuals. The western loggerhead shrike, Lanius ludovicianus excubitorides, is a threatened species in Canada, and its decline is attributed to potential limitations on the wintering grounds. We examined patterns of stablehydrogen isotope (δD) distributions in feathers of loggerhead shrikes, primarily of L. l. excubitorides, during winter at three regions in north and central Mexico, to establish relative abundance and origins of migrants. We also investigated potential movements of Mexican winter resident individuals. Using shrike museum specimens of known summer provenance, a shrike deuterium base map for Mexico was developed from isotopic measurement of feathers of resident shrikes and use of a recently established feather base map for raptors in North America. Stable hydrogen isotope analyses of inner secondary feather (s9) of all loggerhead shrikes examined in Mexico during winter indicated that north-central (Region A), north-eastern (Region B) and south-central (Region C) sites in Mexico consisted of 28.1%, 73.7% and 63.8% of migrant individuals from northern breeding grounds, respectively. Isotopic evidence suggested movements of a few local residents birds (7.9%) into the Chihuahuan desert from south-western USA and north-eastern Mexico to winter.
Simple SummaryA disease outbreak in domestic dogs was reported by a coastal Chilean community following the February 2010 earthquake and tsunami. Using clinical exams and diagnostic testing, canine distemper virus was confirmed. Most dogs seen had never been vaccinated, and the majority of those with positive results were recorded in dogs less than two years of age. There were no facilities to contain or treat dogs locally, and no plan to shelter free-roaming dogs. This observational study demonstrates the great need for disaster preparedness planning in developing countries that includes companion animals.AbstractFollowing the earthquake and tsunami disaster in Chile in February 2010, residents of Dichato reported high morbidity and mortality in dogs, descriptions of which resembled canine distemper virus (CDV). To assess the situation, free vaccine clinics were offered in April and May. Owner information, dog history and signalment were gathered; dogs received physical examinations and vaccines protecting against CDV, and other common canine pathogens. Blood was collected to screen for IgM antibodies to CDV. In total, 208 dogs received physical exams and vaccines were given to 177. IgM antibody titres to CDV were obtained for 104 dogs. Fifty-four dogs (51.9%) tested positive for CDV at the cut off titre of >1:50, but a total of 91.4% of dogs had a detectable titre >1:10. Most of the positive test results were in dogs less than 2 years of age; 33.5% had been previously vaccinated against CDV, and owners of 84 dogs (42.2%) reported clinical signs characteristic of CDV in their dogs following the disaster. The presence of endemic diseases in dog populations together with poor pre-disaster free-roaming dog management results in a potential for widespread negative effects following disasters. Creation of preparedness plans that include animal welfare, disease prevention and mitigation should be developed.
The Loggerhead Shrike (Laniusludovicianus) breedsthroughout North America and various populationsapparently exhibit diverse molt strategies.However, molt in this species and how it may varygeographically is generally poorly known. Weinvestigated molt sequence in 27 breedingLoggerhead Shrikes using stable hydrogen(δD) isotope analysis of flightfeathers. Because feather δD varies with thelatitude at which feathers are grown in NorthAmerica, it is relatively straightforward toidentify those feathers grown south of anindividual's breeding location. We sampled 11feathers per individual to evaluate locations offeather molt between breeding and wintering groundsin North America. Sampling took place in centralSaskatchewan, Canada (n = 18 individuals) andin the southern region of the Saskatchewan-Manitobaborder (n = 9). We found evidencethat shrikes initiated flight feather molt on theirbreeding grounds (P1 and P3) but thenlargely suspended molt until reaching theirwintering areas. The isotopic evidence suggeststhat the first primary (P1, most depleted indeuterium, mean = −103‰) provides information onshrike breeding latitudes while the innermosttertial (S9, most enriched in deuterium, mean = −49‰)provides information on shrike wintering orsouthernmost molting latitudes.
Intratesticular injection of EsterilSol (zinc gluconate neutralized with arginine) is a chemical sterilant for male dogs sometimes used in population control campaigns. Adverse reactions have been reported in 1% to 4% of treated dogs, but detailed histomorphologic descriptions are lacking. During a behavioral study conducted in the Chilean Patagonia in 2012, severe necrosuppurative orchitis and ulcerative dermatitis were observed in 2 of 36 (6%) dogs sterilized with EsterilSol according to the manufacturer's instructions. Reactions were noted on days 8 and 7 postinjection and required scrotal ablation on days 8 and 13, respectively; neither reaction was associated with the injection site. Although self-trauma following administration may have contributed, the cause of the adverse reactions is uncertain. EsterilSol is a relatively uncomplicated method to sterilize male dogs, but the occurrence of severe adverse reactions several days after administration emphasizes the need for the provision of long-term monitoring and veterinary care during sterilization campaigns using this product.
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