Feeding stimulant

Sakata and coworkers suggest that this assay is useful for identifying phagostimu-lants but not attractants. 

Using a separate methodology, Tamburri and Zimmer-Faust (1996) found that oysters consumed numerous species of invertebrate larvae and that their 

Because most investigations of feeding stimulants have been focused on aqua-cultural or similar needs, we do not consider this topic further because few studies provide examples that should be employed when ecological realism is desired. Many of the feeding deterrent assays discussed above could be modified to investigate feeding stimulants. 

Because most studies of marine chemical defenses have manipulated individual compounds or structural traits rather than multiple prey traits, more investigation and development of appropriate methodology is needed. 

Several studies have indicated that the chemical and structural defenses (e.g., CaCOs) that commonly co-occur in both marine plants (calcification) and benthic invertebrates (spicules, calcification) can function either additively or synergisti-cally to reduce susceptibility to consumers (Hay et al. 1994 Schupp Paul 1994 Meyer Paul 1995 Pennings et al. 1996). In one of the more elaborate 

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The class III cytokine receptor family includes two TNE receptors, the low affinity NGE receptor and 7-ceU surface recognition sites that appear to play a role in proliferation, apoptosis, and immunodeficiency. TNE-a (- 17, 000 protein) is produced by astrocytes and microglia and can induce fever, induce slow-wave sleep, reduce feeding, stimulate prostaglandin synthesis, stimulate corticotrophin-releasing factor and prolactin secretion, and reduce thyroid hormone secretion. TNE-a stimulates IL-1 release, is cytotoxic to oligodendrocytes, and reduces myelination this has been impHcated in multiple sclerosis and encephalomyelitis. Astrocyte TNE-a receptors mediate effects on IL-6 expression and augment astrocytic expression of MHC in response to other stimulants such as lEN-y. 

Interspecific chemical cues are also often mixtures. Mixtures of amino acids serve as feeding stimulants in fish. Among mammals, ferrets respond more to mixtures than to pure odors in their foraging responses. The mixtures are thought to contain more information (Apfelbach, 1973). 

Adron, J. W. and Mackie, A. M. (1978). Studies on the chemical nature of feeding stimulants for rainbow trout, Sa/mo a/rdnen Richardson.Jo rndZf FwfiBwZo 12,303-310. 

Although a toxic plant chemical may not fit either category perfectly, those chemicals discussed below that are tissue specific would generally be considered to show specific resistance. It Is interesting to note that those phytochemicals that are especially toxic to one group of Insects are quite often essential dietary Ingredients or feeding stimulants to other Insects that feed primarily on that plant. 

As opposed to the results indicated above, the effect of gossypol on the boll weevil is quite different. Gossypol is a feeding stimulant to the boll weevil (260). Boll weevils feeding on an artificial diet were healthier and had In jroved egg hatch when the gossypol fraction from cotton seed was used as the principle protein source. 

Positive factors Physical stimuli attractants feeding stimulants oviposition stimulants... 

The host range of the tobacco hornworm (Manduca sexta) is limited to selected members of the family Solanaceae. In an effort to better understand the chemical basis for the host plant selection process, we have undertaken an examination of both hornworm preferred and non-preferred members of the Solanaceae. Our investigations have shown this tc be a complex system involving the subtle interaction between such behavioral modulators as (1) Ovipositional stimulants (2) Feeding stimulants and imprinters (3) Anti-feedants (A) Repel-lants (5) Insecticides. The results of these investigations will be discussed. 

Figure 4. Comparison of nicandrenone structure (top) to the proposed structure of the feeding stimulant (bottom). R = glycosyl.

It is interesting to note that the feeding stimulant is the glycoside of a withanollde, a known class of allomones unique to... 

For example, gossypol, a terpenoid substance, is an allomone that limits herbivory by several lepidopteran species on cotton (Gossypium spp., MalvaceaeK whereas it is a kairomone for the boll weevil, Anthonomus grandis and acts as a feeding stimulant for this insect (3,21,22) ... 

Nojima, S., Sakuma, M. and Kuwahara, Y. (1996). Polyethylene glycol film method a test for feeding stimulants of the German cockroach, Blattella germanica (L.) (Dictyoptera Blattellidae). Applied Entomology and Zoology 31 537-546. 

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