Effect Of Fleas Research Articles

Biochemical parameters of blood serum of dogs for ctenocephalidosis

One of the most common ectoparasitic diseases of domestic carnivorous animals is ctenocephalidosis caused by fleas of the genus Ctenocephalides. The peculiarity of this invasion is a chronic course associated with the constant attack of parasitic insects on the animal, accompanied by severe itching, the occurrence of alopecia, the development of eczema, dermatitis and the subsequent introduction of pathogenic microflora into the damaged tissue. The aim of the study was to investigate the effect of fleas of the genus Ctenocephalides on the biochemical parameters of the blood serum of invaded dogs. Three groups of animals were formed: a control (clinically healthy dog) and two experimental animals (infected by the parasitic insect Ctenocephalides spp.) with different intrusion rates. In blood serum determined: the content of total protein, albumin, total bilirubin, creatinine, urea, glucose, cholesterol, phosphorus, potassium, calcium, magnesium, alanine aminotransferase activity, aspartate aminotransferase, alkaline phosphate. Conducted studies found that rates the intensity of infestation significantly influence the changes that occur in blood serum infested dogs. The intensity of ctenocephalidosic infestation of up to 15 specimens of fleas in the animal in their blood serum showed a significant decrease in albumin content (by 22.37 %) compared to that in clinically healthy dogs. The intensities of xenophalphalous infestation of 16–47 specimens of fleas per animal in the serum of the infected animals showed a significant decrease in albumin (by 29.28 %), glucose (by 25.29 %), and cholesterol (by 35.59 %) relative to similar indicators clinically healthy animals. At the same time in the serum of the infested dogs the content of total bilirubin (by 15.73 %), as well as the activity of alanine aminotransferase (1.4 times), aspartate aminotransferase (1.4 times) and alkaline phosphatase (2 times). The results of the experimental data extend the already existing data on the pathogenesis of fleas parasites in dogs, and will also allow the effective treatment of diseased animals.

Effects of fleas on nest success of Arctic barnacle geese: experimentally testing the mechanism

Parasites have detrimental effects on their hosts’ fitness. Therefore, behavioural adaptations have evolved to avoid parasites or, when an individual is already in contact with a parasite, prevent or minimize infections. Such anti‐parasite behaviours can be very effective, but can also be costly for the host. Specifically, ectoparasites can elicit strong host anti‐parasite behaviours and interactions between fleas (Siphonaptera) and their hosts are one of the best studied. In altricial bird species, nest fleas can negatively affect both parent and offspring fitness components. However, knowledge on the effects of fleas on precocial bird species is scarce. Research on geese in the Canadian Arctic indicated that fleas have a negative impact on reproductive success. One possible hypothesis is that fleas may affect female incubation behaviour. Breeding females with many fleas in their nest may increase the frequency and/or duration of incubation breaks and could even totally desert their nest. The aim of our study was to 1) determine if a similar negative relationship existed between flea abundance and reproductive success in our study colony of Arctic breeding barnacle geeseBranta leucopsisand 2) experimentally quantify if such effects could be explained by a negative effect of nest fleas on female behaviour. We compared host anti‐parasite and incubation behaviour between experimentally flea‐reduced and control nests using wildlife cameras and temperature loggers. We found that flea abundance was negatively associated with hatching success. We found little experimental support, however, for changes in behaviour of the breeding female as a possible mechanism to explain this effect.

Of fleas and geese: the impact of an increasing nest ectoparasite on reproductive success

Past studies on the relationship between nest ectoparasites and avian fitness have been primarily limited to altricial hosts. Life history strategies of precocial and altricial birds vary considerably, limiting our ability to infer the effect of nest parasites on fitness of precocial species. Ross's Chen rossii and lesser snow goose Chen caerulescens caerulescens populations have been growing at unprecedented high rates. New limiting factors on vital rates of these precocial birds may arise after populations have been released from previously regulating factors. The flea Ceratophyllus vagabundus vagabundus is an apparently newly emerging nest parasite in the arctic goose colony at Karrak Lake, Nunavut, Canada. We examined the relationship between flea abundance (measured by the proportion of goose eggs covered by blood in each nest) and goose reproductive success from 2001–2004. In three of four years of study, nest success was inversely related to flea abundance in nests. Despite the potential for high costs to individuals, the overall effects of fleas on goose nesting success have thus far been small. We demonstrated that nest parasites negatively influence reproductive success of precocial bird hosts despite host life history strategy of leaving the nest quickly after hatch, which results in minimal exposure to nest parasites compared to altricial birds that raise their young in the nest.

Ectoparasitism in marsh tits: costs and functional explanations

Among hole-nesting birds, the blood-sucking hen flea is a common parasite affecting both nestlings and parents. By adding fleas to marsh tit (Parus palustris) nests, I aimed to investigate the effect of fleas on nestling growth rate and parental effort as well as evaluating a potential mechanism by which fleas affect nestlings (i.e., resting metabolic rate; RMR). Nestlings from flea-infested broods were lighter than nestlings from control broods. This reduced growth rate was evident as soon as 3 days after adding extra fleas to the nest, but the reduction did not increase after this initial drop in mass. Parents did not alter their feeding frequency in response to the manipulation; thus the small size of nestlings in manipulated nests seems to be directly caused by the fleas. Mass-specific RMR was significantly higher in nestlings from flea-infested nests compared to nestlings from control nests. I used the results to evaluate the suggested mechanisms for parasite-related decrease in host growth rate. The increase in RMR and the very rapid reduction in nestling growth rate after experimental addition of fleas can be explained by an immune reaction, mainly by the innate immune system, to substances in the saliva of the fleas. (Less)

Immunocompetence of nestling great tits in relation to rearing environment and parentage

Theoretical models of host–parasite coevolution assume a partially genetic basis to the variability in susceptibility to parasites among hosts, for instance as a result of genetic variation in immune function. However, few empirical data exist for free–living vertebrate hosts to support this presumption. In a cross–fostering experiment with nestling great tits, by comparing nestlings of the same origin we investigated (i) the variance in host resistance against an ectoparasite due to a common genetic origin, (ii) the effect of ectoparasite infestation on cell–mediated immunity and (iii) the variance in cell–mediated immunity due to a common genetic origin. Ectoparasitic hen fleas can impair the growth of nestling great tits and nestling growth was therefore taken as a measure of host susceptibility. A common origin did not account for a significant part of the variation in host susceptibility to fleas. There was no significant overall effect of fleas on nestling growth or cell–mediated immunity, as assessed by a cutaneous hypersensitivity response. A common rearing environment explained a significant part of the variation in cell–mediated immunity among nestlings, mainly through its effect on nestling body mass. The variation in cell–mediated immunity was also related to a common origin. However, the origin–related variation in body mass did not account for the origin–related differences in cell–mediated immunity. The results of the present study thus suggest heritable variation in cell–mediated immunity among nestling great tits.

Effects of ectoparasites on breeding success of great tits (Parus major) and pied flycatchers (Ficedula hypoleuca) in an air pollution gradient

Numbers of ectoparasitic blow fly (Protocalliphora azurea) larvae (Diptera: Calliphoridae), adult and larval hen fleas, Ceratophyllus gallinae (Siphonaptera: Ceratophyllidae), and other nest-dwelling insects were counted from the nests of the great tit, Parus major, and the pied flycatcher, Ficedula hypoleuca, in southwestern Finland around a factory complex emitting large quantities of sulphuric oxides and heavy metals. Protocalliphora azurea larvae were more frequently found in the nests of P. major than in those of F. hypoleuca. The prevalence of P. azurea larvae tended to be lower in polluted areas. The number of P. azurea larvae correlated positively with nest size and brood size of P. major. This may be caused by difficulties in sanitation of large and crowded nests. The numbers of fleas and their larvae were negatively affected by moisture in the nests. Nests of F. hypoleuca contained more adult fleas in polluted areas. This may indicate reduced resistance of birds exposed to heavy metals, but other possibilities are also discussed. We found a detrimental effect of P. azurea larvae on the growth of P. major nestlings, and an effect of fleas on mortality of F. hypoleuca nestlings, but these effects were not enhanced by air pollution. We conclude that the ectoparasites studied, at densities observed in our study area, are of minor importance in determining the breeding success of these two bird species.