A test of energetic trade-offs between growth and immune function in watersnakes

Abstract

Energy budgets explain how organisms allocate energetic intake to accomplish essential processes. A likely life history trade-off occurs between growth and immune response in juvenile organisms, where growth is important to avoid predation or obtain larger prey and immune response is essential to survival in the presence of environmental pathogens. We examined the innate (wound healing) and adaptive (lymphoid tissue, thymus and spleen) components of immune response along with growth in two populations of the diamond-backed watersnake Nerodia rhombifer raised in a common environment. We found that neonate snakes born to females from populations characterized by different predator and prey environments did not differ in energetic intake, but snakes from the population containing large prey grew significantly faster than those from a population containing small prey. Thymus mass, when corrected for body mass, was larger in snakes from the small prey population than in snakes from the large prey population. Additionally, the snakes from the population containing small prey healed significantly faster than those from the population containing large prey. Thus, we detected a negative correlation between growth (over a 4-month period) and wound healing across populations that is suggestive of an energetic trade-off between growth and immune response. The differences observed in growth and immune response among these two populations appear to suggest different energy allocation strategies to maximize fitness in response to differing conditions experienced by snakes in the two populations.

Physiological responses to elevated temperature across the geographic range of a terrestrial salamander

“…slower wound healing) than control individuals (Thomas and Woodley, 2015). A suppressed immune response may be a result of energetic tradeoffs, where chronically stressed individuals allocate more energy towards physiological maintenance than immune responses (Korfel et al, 2015). By contrast, increased levels of plasma CORT did not affect locomotor performance in Allegheny dusky salamanders (Desmognathus ochrophaeus), although other stressors (i.e.…”

Repeatability and sources of variation of the bacteria‐killing assay in the common snapping turtle

“…An increase in bactericidal capacity with age and/or body size has been found in a number of vertebrates (Hopkins et al, 2016;Madsen, Ujvari, Nandakumar, Hasselquist, & Holmdahl, 2007;Palacios et al, 2011;Tieleman et al, 2010;Wilcoxen, Boughton, & Schoech, 2010), and such ontogenetic differences may be due to maturation processes and/or stage-specific differences in resource allocation. Mounting an immune response is energetically costly and can constrain other life-history characteristics such as growth (Korfel, Chamberlain, & Gifford, 2015;Soler, de Neve, Perez-Contreras, Soler, & Sorci, 2003;van der Most, de Jong, Parmentier, & Verhulst, 2011). Young or small individuals may preferentially allocate resources toward growth over other physiological processes such as immunity because early growth can have fitness consequences in adulthood such as increased fecundity or larger adult body size (Stearns & Koella, 1986).…”

“…Young or small individuals may preferentially allocate resources toward growth over other physiological processes such as immunity because early growth can have fitness consequences in adulthood such as increased fecundity or larger adult body size (Stearns & Koella, 1986). Larger individuals are often less vulnerable to predators (Janzen, 1993;Sparkman, Bronikowski, Billings, Von Borstel, & Arnold, 2013), have access to larger prey resources (Arendt, 1997;Korfel et al, 2015), and may be better able to survive harsh environmental conditions (Bronikowski, 2000;Kissner & Weatherhead, 2005), which would favor resource allocation to early growth over immunity. Alternatively, we cannot eliminate the possibility that the captive rearing environment may have contributed to the differences between wild caught adult females and lab-reared hatchlings.…”

Contrasting latitudinal patterns of life‐history divergence in two genera of new world thrushes (Turdinae)

“…However, higher parental investment per nestling may simply reflect increased investment to produce high‐quality young achieved through reduced clutch size rather than an increase in food availability in tropical regions (Martin ). Because development of physiological components such as immune function appear to tradeoff with offspring growth (Korfel et al ), higher per‐nestling feeding rates could facilitate increased offspring quality, reducing juvenile and adult mortality, without sacrificing growth. It is important to note that nest predation can influence feeding rates (Skutch , Martin et al , b, ).…”