Compensatory feeding in response to variable food quality by Melanoplus differentialis

Abstract

Abstract. The behavioural mechanisms driving compensatory food consumption in response to dietary dilution as well as the relationship between feeding time and food residence time (i.e. digesta retention time in the gut) were studied using the non‐diapausing strain of the grasshopper Melanoplus differentialis (Thomas) (Orthoptera: Acrididae). 3‐day‐old, sixth‐instar nymphs and 3‐day‐old adults were fed artificial diets containing 1%, 3% and 5% total nitrogen (N) at 30d̀C, LD 14:10h; the feeding behaviour was recorded using electronic monitoring devices connected to microcomputers for 24 h. The percentage of time spent feeding increased linearly as diets were diluted using non‐digestible cellulose from 5% to 1% N. This response was due to an increase in the number of meals while the meal duration of a feeding bout was unaltered. Sixth‐instar nymphs spent about 40% more time feeding than the larger adults. The increased feeding time in nymphs resulted from both more frequent feeding bouts and longer meal duration. Feeding time and food residence time were highly negatively related.

Importance of dietary nitrogen and carbohydrates to survival, growth, and reproduction in adults of the grasshopper Ageneotettix deorum (Orthoptera: Acrididae)

“…Horse Charge contains 6% (dry weight) of both total N and TNCs (Yang and Joern 1994a). However, the basal amount of Horse Charge in each of the present diets contributed 2% and 1% (dry weight) of the total carbohydrate and N level, respectively.…”

Resource-mediated impact of spider predation risk on performance in the grasshopper Ageneotettix deorum (Orthoptera: Acrididae)

“…In grasshoppers, successful performance during immature stages of the lifecycle requires sufficient food, the bulk amount dependent primarily upon nutritional intake (Heidorn and Joern 1987;Joern and Alward 1988;Yang and Joern 1994;Simpson et al 1995;Joern and Behmer 1998;Raubenheimer and Simpson 1999). Assuming that high quality plant material exists, grasshoppers should search for and consume resources that will maximize growth, survival, and reproduction (Joern et al 1986;Joern and Gaines 1990;Hinks et al 1993;Belovsky et al 1996).…”

“…Based on known dietary requirements (Yang and Joern 1994;Joern and Behmer 1998;Joern 1998, 2000) and susceptibility of grasshoppers to predation risk from lycosid spiders Schmitz et al 1997;Joern 1998, 2000;Schmitz 1998;Okuyama 1999), we hypothesized that immature A. deorum would respond positively to fertilized plant material and negatively to the risk of spider predation. Given prior evidence of compensatory interactions between resource quality and predator avoidance (Price et al 1980;Beckerman et al 1997;Oedekoven and Joern 2000), we also investigated the effects that combinations of these treatments had on performance responses.…”

Nutritional physiology of life history trade-offs: how food protein-carbohydrate content influences life-history traits in the wing-polymorphic cricketGryllus firmus

“…Crickets are opportunistic feeders (Capinera et al, 2004), so the nutritional content of their food can be highly variable. Animals, including insects, are known to employ compensatory mechanisms when eating foods that are nutritionally imbalanced (Simpson and Raubenheimer, 1993;Simpson et al, 2002;Cook et al, 2010) or have low-nutrient concentration (Yang and Joern, 1994;Slansky and Wheeler, 1989;Lee et al, 2004). Furthermore, multiple studies have revealed that reproductive output and lifespan are also responsive to protein and carbohydrate concentrations and ratios (Maklakov et al, 2008;Lee et al, 2008, Roeder andBehmer, 2014).…”