What makes a host profitable? Parasites balance host nutritive resources against immunity.

Numerous host qualities can modulate parasite fitness, and among these, host nutritive resources and immunity are of prime importance. Indeed, parasite fitness increases with the amount of nutritive resources extracted from the host body and decreases with host immune response. To maximize fitness, parasites have therefore to balance these two host components. Yet, because host nutritive resources and immunity both increase with host body condition, it is unclear whether parasites perform better on hosts in prime, intermediate, or poor condition. We investigated blood meal size and survival of the ectoparasitic louse fly Crataerina melbae in relation to body condition and cutaneous immune response of their Alpine swift (Apus melba) nestling hosts. Louse flies took a smaller blood meal and lived a shorter period of time when feeding on nestlings that were experimentally food deprived or had their cutaneous immune response boosted with methionine. Consistent with these results, louse fly survival was the highest when feeding on nonexperimental nestlings in intermediate body condition. Our findings emphasize that although hosts in poor condition had a reduced immunocompetence, parasites may have avoided them because individuals in poor condition did not provide adequate resources. These findings highlight the fact that giving host immunocompetence primary consideration can result in a biased appraisal of host-parasite interactions.

Mating does not influence reproductive investment, in a viviparous lizard.

Mating is crucial for females that reproduce exclusively sexually and should influence their investment into reproduction. Although reproductive adjustments in response to mate quality have been tested in a wide range of species, the effect of exposure to males and mating per se has seldom been studied. Compensatory mechanisms against the absence of mating may evolve more frequently in viviparous females, which pay higher direct costs of reproduction, due to gestation, than oviparous females. To test the existence of such mechanisms in a viviparous species, we experimentally manipulated the mating opportunity of viviparous female lizard, Lacerta (Zootoca) vivipara. We assessed the effect of mating on ovulation, postpartum body condition and parturition date, as well as on changes in locomotor performances and body temperatures during the breeding cycle. Female lizards ovulated spontaneously and mating had no influence on litter size, locomotor impairment or on selected body temperature. However, offspring production induced a more pronounced locomotor impairment and physical burden than the production of undeveloped eggs. Postpartum body condition and parturition dates were not different among females. This result suggests that gestation length is not determined by an embryonic signal. In the common lizard, viviparity is not associated with facultative ovulation and a control of litter size after ovulation, in response to the absence of mating.

Étude éco-épidémiologique sur l’infection par Francisella tularensis au Québec

Au Canada, Francisella tularensis, une bactérie zoonotique causant la tularémie, affecte principalement le lièvre d’Amérique, le rat musqué et le castor. Malgré les nombreuses études sur cette maladie, les connaissances sur l’écologie et les réservoirs naturels de la tularémie demeurent limitées. Une étude transversale a été réalisée afin d’estimer la prévalence d’infection par F. tularensis chez le lièvre d’Amérique, le rat musqué et le coyote dans quatre régions du Québec (Canada) et de décrire le risque d’infection d’après des caractéristiques individuelles (âge, sexe et état de chair) et environnementales. D’octobre 2012 à avril 2013, 345 lièvres d’Amérique, 411 rats musqués et 385 coyotes capturés par des trappeurs ont été échantillonnés. Les caractéristiques environnementales autour du site de capture ont été extraites de base de données géographiques. La séroprévalence (test de microagglutination) était de 2.9% chez les coyotes, 0.6% chez les lièvres et 0% chez les rats musqués. Tous les rats musqués et les lièvres étaient négatifs à une PCR en temps réel réalisée à partir d’un pool de foie, rein, rate et poumon; par contre, le type AI a été détecté dans les organes individuels des deux lièvres séropositifs. Des analyses de régression logistique exacte ont démontré que l’âge était un facteur de risque pour la séropositivité du coyote, ainsi que la proportion de forêts et la proportion de l’environnement considéré approprié pour le lièvre autour de la localisation de capture des coyotes. Les résultats de cette étude suggèrent la présence du cycle terrestre dans les régions étudiées.

Suburban immigrants to wildlands disrupt honest signaling in ultra-violet plumage

Urbanization changes habitat in a multitude of ways, including altering food availability. Access to human-provided food can change the relationship between body condition and honest advertisements of fitness, which may result in changes to behavior, demography, and metapopulation dynamics. We compared plumage color, its relationship with body condition and feather growth, and use as signal of dominance between a suburban and a wildland population of Florida Scrub-Jay (Aphelocoma coerulescens). Although plumage color was not related to body condition at either site, suburban birds had plumage with a greater proportion of total reflectance in the ultra-violet (UV) and peak reflectance at shorter wavelengths. Despite the use of plumage reflectance as a signal of dominance among individuals in the wildlands, we found no evidence of status signaling at the suburban site. However, birds emigrating from the suburban site to the wildland site tended to be more successful at acquiring breeder status but less successful at reproducing than were immigrants from an adjacent wildland site, suggesting that signaled and realized quality differ. These differences in signaling content among populations could have demographic effects at metapopulation scales and may represent an evolutionary trap whereby suburban immigrants are preferred as mates even though their reproductive success relative to effort is lower.

Parâmetros métricos da traqueia e suas correlações com o perímetro torácico, peso e comprimento corporal de cães sem raça definida (Canis familiaris, Linnaeus, 1758)

The present study aimed to analyze metric data from the trachea of dogs and to correlate them with the thoracic girth, body length and weight. We used 48 dogs of unknown breed, 19 males and 29 females. The animals were weighed and then body length, thoracic girth, length and diameter of the trachea, and the number of tracheal rings were measured. The weight of dogs ranged from 4.2 to 21.5 kg, body length from 40.6 to 81.0 cm and thoracic girth from 36.0 to 63.5 cm. The trachea exhibited a total number of tracheal rings between 32 and 43, length between 13.0 and 23.4 cm, diameter of the cervical portion between 11.0 and 23.5 mm and in the thoracic portion between 8.2 and 20.9 mm. We also evaluated the tracheal termination skeletopy, which maintained relations with the 2nd (2.0%), 3 (6.3%), 4 (20.8%) or 5 (12.5%) intercostal spaces, and with the 3rd (6.3%), 4th (35.4%) or 5th (16.7%) ribs. Strong positive correlations of tracheal length with body weight (rS = 0.756, p <0.001), body length (r = 0.808, p <0.001) and thoracic girth (r = 0.735, p <0.001) were found. Therefore, the anatomical study of the trachea provides morphological subsidies for the realization of clinical and surgical procedures in this organ, being an important tool in veterinary practice.

Influência da ingestão de matéria seca e da condição corporal na produção in vitro de embriões bovinos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Estresse nos morcegos Artibeus obscurus e Artibeus fimbriatus (Chiroptera, Phyllostomidae) como resposta à perturbação ambiental

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Resposta fenotípica integrada do morcego frugívoro Artibeus lituratus (Chiroptera, phyllostomidae) frente à redução da qualidade da dieta

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Spirulina e exercício na recuperação de ratos submetidos à desnutrição protéica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Energética alimentar de Gracilinanus microtarsus (Didelphimorphia: Didelphidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação da pressão arterial sistêmica em cães obesos: comparação entre os métodos oscilométrico e doppler ultrassônico

Obesity is the most common nutritional problem in dogs and it can cause various harmful effects on animal health. However, the effect of this condition on systolic blood pressure (SBP) in obese dogs is controversial. The indirect method of measuring PAS is the most commonly used in veterinary medicine for the diagnosis of systemic hypertension, because it is more practical and easy to access. There is little scientific information about the comparison of the two non- invasive methods of measurement of blood pressure in obese dogs. Therefore, the objective of this study was to evaluate the SBP in obese dogs by comparing both indirect methods of measuring blood pressure, with oscillometric and doppler vascular in order to verify the differences in blood pressure values, but also the best method to assess the SBP dogs in this body score condition. The study complain blood pressure measurement of 50 dogs, with were divided in obese dogs with mean body condition score (BCS) of 8.42 +/- 0.50 (n = 25) and dogs with ideal BCS of 4.56 +/- 0.51 (n = 25). At comparison of blood pressure values, SBP values obtained by doppler method (152 +/- 16mmHg) were higher than the oscillometric (136 +/- 11mmHg). Correspondence analysis determined by multivariate statistical analysis showed correlation between body condition and the procedure of the SBP. These findings suggest that the indirect method doppler can better reflect the SBP in obese dogs.

Estudos helmintológicos em quirópteros no bioma Amazônia

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Outbreak of severe foot rot associated with benign Dichelobacter nodosus in an Alpine ibex colony in the Swiss Prealps.

An outbreak of foot rot occurred in the ibex colony "Vanil Noir" in Switzerland from May to December 2014. This article describes field observations and the analyses carried out on the limbs of 3 animals submitted for postmortem examination. Disease signs observed in the field included lameness, poor body condition and overgrown hooves. Macroscopic examination of selected limbs revealed severe lesions in all of them, including interdigital inflammation with ulceration and malodorous exudation. Histological changes were consistent with chronic laminitis with bone resorption, which was not detected at radiographical examination. Grocott-positive organisms compatible with Dichelobacternodosus were detected in the lesions. Samples collected from the lesions were positive by polymerase chain reaction for benign D. nodosus, which is typically associated with only mild lesions in domestic sheep. Whether D. nodosus is endemic in the colony or had previously been transmitted from sympatric domestic livestock is unclear. The unusual warm and humid weather conditions in 2014 may well have contributed to the outbreak.

(Table 1) Concentration of persistent organic pollutants in blood plasma of glaucous gulls (Larus hyperboreus) from Bjørnøya

Unpredictable changes in the environment stimulate the avian hypothalamo-pituitary-adrenal axis to produce corticosterone, which induces behavioural and metabolic changes that enhance survival in the face of adverse environmental conditions. In addition to profound environmental perturbations, such as severe weather conditions and unpredictable food shortages, many Arctic-breeding birds are also confronted with chronic exposure to persistent organic pollutants (POPs), some of which are known to disrupt endocrine processes. This study investigated the adrenocortical function of a top predator in the Arctic marine environment, the glaucous gull (Larus hyperboreus). High concentrations of organochlo-rines, brominated flame retardants and metabolically-derived products in blood plasma of incubating glaucous gulls were associated with high baseline corticosterone concentrations in both sexes and a reduced stress response in males. Contaminant-related changes in corticosterone concentration occurred over and above differences in body condition and seasonal variation. Chronically high corticosterone concentrations and/or a compromised adrenocortical response to stress can have negative effects on the health of an individual. The results of the present study suggest that exposure to POPs may increase the vulnerability of glaucous gulls to environmental stressors and thus could potentially compromise their ability to adapt to the rapidly changing environmental conditions associated with climate change that are currently seen in the Arctic.

Physiological evidence for reproductive suppression in the introduced population of brown tree snakes (Boiga irregularis) on Guam

Introduced species are an increasingly pervasive problem. While studies on the ecology and behavior of these pests are numerous, there is relatively little known of their physiology, specifically their reproductive and stress physiology. One of the best documented introduced pest species is the brown tree snake, Boiga irregularis, which was introduced onto the Pacific island of Guam sometime around World War II. The snake is responsible for severely reducing Guam's native vertebrates. We captured free-living individuals throughout the year and measured plasma levels of stress and sex hormones in an effort to determine when they were breeding. These data were compared to reproductive cycles from a captive population originally collected from Guam. Free-living individuals had chronically elevated plasma levels of the stress hormone corticosterone and basal levels of sex steroids and a remarkably low proportion were reproductively active. These data coincide with evidence that the wild population may be in decline. Captive snakes, had low plasma levels of corticosterone with males displaying a peak in plasma testosterone levels during breeding. Furthermore, we compared body condition between the free-living and captive snakes from Guam and free-living individuals captured from their native range in Australia. Male and female free-living snakes from Guam exhibited significantly reduced body condition compared to free-living individuals from Australia. We suggest that during the study period, free-living brown tree snakes on Guam were living under stressful conditions, possibly due to overcrowding and overexploitation. of food resources, resulting in decreased body condition and suppressed reproduction. (C) 2004 Elsevier Ltd. All rights reserved.