Anthelmintic treatment affects behavioural time allocation in a free-ranging ungulate

Worsley‐Tonks, Katherine E. L.; Ezenwa, Vanessa O.

doi:10.1016/j.anbehav.2015.07.018

Cited by 13 publications

(12 citation statements)

References 67 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, group size was also positively associated with feeding rate, and GIN-infected (control) individuals in the largest groups fed at rates that were higher than individuals in the smallest groups. Our previous work has shown that, on average, treated individuals feed at a higher rate than do controls [13]. Interestingly, here we show that parasite clearance allowed treated individuals to feed at a relatively consistent rate irrespective of group size.…”

Section: Discussionsupporting

confidence: 66%

“…We monitored group sizes and GIN infection rates of nine anthelmintic-treated females to evaluate the effect of group size on parasite reinfection. Treatment significantly reduced GIN burdens in treated females (as compared to controls) for approximately 120 days [13], and we monitored individuals for approximately 500 days following treatment, from 4 July 2011 to 12 November 2012. We used regularly occurring road transects distributed throughout the day (06.30 -18.30 h) to locate animal groups.…”

Section: (B) Group Size and Gin Infectionmentioning

confidence: 99%

See 1 more Smart Citation

Social living simultaneously increases infection risk and decreases the cost of infection

Ezenwa

Worsley‐Tonks

2018

Proc. R. Soc. B.

Self Cite

View full text Add to dashboard Cite

Elevated parasite infection risk is considered to be a near-universal cost of social living. However, living in groups may also provide benefits that reduce the negative impacts of infection. These potential ‘tolerance’ benefits of living socially are theoretically possible, but have rarely been described. In this study, we used an anthelmintic treatment experiment in wild Grant's gazelles ( Nanger granti ), who are commonly infected with gastrointestinal nematodes (GIN), to show that social living confers both costs and benefits related to GIN parasitism. We show that although larger group size increases GIN infection risk, a key cost of GIN infection—the suppression of food intake—is simultaneously moderated by living in larger groups. Our findings help illuminate the complex role parasites play in the evolution of host social behaviour.

show abstract

Section: Discussionsupporting

confidence: 66%

Section: (B) Group Size and Gin Infectionmentioning

confidence: 99%

Social living simultaneously increases infection risk and decreases the cost of infection

Ezenwa

Worsley‐Tonks

2018

Proc. R. Soc. B.

Self Cite

View full text Add to dashboard Cite

show abstract

“…In livestock, reduced forage intake is a common behavioural response to GI worm infection, which is thought to be associated with the up-regulation of anti-worm immunity (Colditz, 2008;Coop & Holmes, 1996). A few studies have also found evidence of worminduced anorexia in semi-captive and free-ranging hosts, suggesting that this response may be widespread in ungulates (Arneberg, Folstad, & Karter, 1996;Worsley-Tonks & Ezenwa, 2015). We used the nitrogen content of host faeces to quantify variation in buffalo intake rates since this measure has previously emerged as a key non-invasive indicator of intake rate in this species (Ryan et al, 2012).…”

Section: Host Responses To Infectionmentioning

confidence: 99%

Differential host responses to parasitism shape divergent fitness costs of infection

et al. 2017

Self Cite

View full text Add to dashboard Cite

Fitness costs of infection are fundamental to understanding the ecology and evolution of host–parasite interactions. However, these costs, and particularly their underlying mechanisms, are challenging to evaluate in wild populations. Here, we quantified total and species‐specific costs of gastrointestinal worms on African buffalo, by combining the power of an anthelmintic treatment experiment that perturbed the entire worm community with a longitudinal study that tracked the two most dominant community members. Reducing all worms improved buffalo body condition, which was strongly associated with increases in survival and reproduction. Species‐specific analyses revealed that condition‐mediated fitness costs of infection differed between parasite species. Hosts that gained the blood‐sucking worm Haemonchus, lost condition, and this loss may have been mediated by reductions in forage intake. Hosts that resisted Haemonchus by elevating IL‐4 and eosinophil immune defences were able to reduce their parasite loads and gain back condition. Conversely, hosts that gained Cooperia, a less pathogenic worm, gained condition and had higher survival and reproductive success. Elevating immune defences had no effect on Cooperia abundance. Coupled with the positive relationship observed between Cooperia and host condition, our data suggest that hosts might benefit from tolerating Cooperia rather than incurring the costs of resistance. Overall, our study reveals that differential host responses to parasites play a key role in mediating the costs of infection. A http://onlinelibrary.wiley.com/doi/10.1111/1365-2435.12951/suppinfo is available for this article.

show abstract

“…Parasites can affect a host's growth and performance, across multiple taxa and life stages and at all levels from individual host performance to community function and structure (Barber, Hoare, & Krause, ; Craig, Jones, Pilkington, & Pemberton, ; Fenner & Bull, ; Hatcher, Dick, & Dunn, ; Poulin, ; Worsley‐Tonks & Ezenwa, ). Nonetheless, most research into the effects of parasitism has come from laboratory studies conducted under artificial conditions, or correlative field surveys from which it is not possible to unambiguously identify causal effects (Crump & Pounds, ; Kelehear, Brown, & Shine, ).…”

Section: Introductionmentioning

confidence: 99%

“…For example, global amphibian declines have stimulated investigations into the biology of microparasites potentially driving such declines; an iridovirus, an oomycete, ranaviruses and a zoosporic fungus Batrachochytrium dendrobatidis (Blaustein & Kiesecker, 2002;Collins, 2010;Dang, Searle, & Blaustein, 2017;Kelehear et al, 2009). Infection by macroparasites also has negative effects on amphibians of many species (Koprivnikar et al, 2012) although overall, the effects of parasites on their hosts may have been underestimated (Dobson & Hudson, 1992;Minchella & Scott, 1991;Worsley-Tonks & Ezenwa, 2015).…”

mentioning

confidence: 99%

The costs of parasite infection: Effects of removing lungworms on performance, growth and survival of free‐ranging cane toads

2017

View full text Add to dashboard Cite

Most research on the effects of parasites on their hosts has focused on the parasites of mammals or birds (especially, domesticated taxa) rather than systems in which the hosts are ectothermic wildlife species. We used experimental methods (antihelminthic drugs) to quantify the effects of lungworms (Rhabdias pseudosphaerocephala) on their anuran hosts, the invasive cane toad (Rhinella marina). In captivity, eradicating lungworms enhanced toad activity (measures of boldness and level of spontaneous activity), performance (locomotor speed, climbing ability) and foraging success (feeding rate). In free‐ranging toads (n = 123) at a site in tropical Australia, eradicating lungworm infection increased rates of host survival by 8%, movement by 20%, growth by 28% and elaboration of male secondary sexual characteristics by 30%. The presence of the lungworm thus has a substantial negative effect on fitness‐related traits of the host. Given their long shared evolutionary history and the mild inflammatory and immune response elicited by the parasite in the host, the magnitude of the effects of parasite removal were surprising. Parasites may impose hidden costs, related to modification of host behaviour or metabolism. Experimental removal of parasites can be a useful means of quantifying costs of infection. A http://onlinelibrary.wiley.com/doi/10.1111/1365-2435.12992/suppinfo is available for this article.

show abstract

Anthelmintic treatment affects behavioural time allocation in a free-ranging ungulate

Cited by 13 publications

References 67 publications

Social living simultaneously increases infection risk and decreases the cost of infection

Social living simultaneously increases infection risk and decreases the cost of infection

Differential host responses to parasitism shape divergent fitness costs of infection

The costs of parasite infection: Effects of removing lungworms on performance, growth and survival of free‐ranging cane toads

Contact Info

Product

Resources

About