• Ocean Science Journal
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• v.42 no.3
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• pp.193-197
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• 2007

The food selectivity of tethered females of the copepod Calanus helgolandicus was examined by using the colorimetric approach. First, feeding behavior of the copepod did not show any differences between the red-color stained with neutral red and non-stained diets using the diatom Coscinodiscus curvatulus. Then, the copepods were fed a mixtures of two diets, the diatom C. curvatulus, stained with neutral red, and the dinoflagellate Gymnodinium sanguineum for $14\sim60$ minutes of feeding duration. The foregut colors of females were examined using a stereo-microscope and a video monitor. The foreguts of animals fed with a high density of diatoms in mixed diets showed a dark red color, whereas those fed with a high density of dinoflagellate in mixed diets were a dark yellow. The results suggest that this species of copepod may not selectively feed either one of the diets used for this study. Their feeding activity may be more likely related to the density of available prey in their environment. Therefore, this quick and easy colorimetric approach could provide very useful information, like the pre-screening procedure before designing and conducting the time-consuming and complex feeding experiments to understand the feeding ecology of copepods.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.6
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• pp.651-654
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• 1996

The effect of guanethidine on feeding behavior was investigated in the chicken. Graded levels of chronically administered guanethidine, an adrenergic neurone blocker, at 0, 25, 50 and 100 mg/kg body weight, decreased body weight gain and food intake in a dose dependent manner. The effect of acute guanethidine administration on crop emptying rate of the chicken was also investigated. The highest level (10 mg i.v./kg body weight) of guanethidine significantly delayed crop emptying compared with the control. These results suggest that the sympathetic nervous system in the chicken is an important factor for the regulation of feeding behavior associated with food passage from the crop.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.655-656
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• 2008

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.2
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• pp.159-168
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• 2010

This study was carried out to investigate the effects of by-product mixing silage feeding on the eating and ruminating behavior of fattening Hanwoo steer. A total of 12 Hanwoo steers (21 months old) were divided into three feeding groups and assigned to 3 dietary treatments: control (C: concentrate + ad libitum feeding of rice straw), and by-product mixing silage groups (T1: concentrate + 1 kg restricted feeding of by-product mixing silage + ad libitum feeding of rice straw, T2: concentrate + ad libitum feeding of by-product mixing silage). Eating behaviors were observed for 48 hours. Total feed intake was high in the order of T1 > C > T2, but not significantly different among the treatments. The eating and chewing time were significantly higher in C than by-product mixing silage treatments (P<0.05). Ruminating and resting time were not significantly different among the treatments. Number of bolus, number of total chews and number of chews per bolus were not significantly different among the treatments. But ruminating time per bolus and FVI (feed value index) were significantly higher in C than T1 and T2 (p<0,01, 0.05). Bolus per minute was the highest in T1 (p<0.01). Number of drinking was significantly higher in T2 than C and T1 (p<0.05), but defecating and urinating were not significantly difference among the treatments. Eating rate was the highest in T2 (p<0.05), but ruminating and chewing efficiency were not significantly difference among the treatments. Consequently, there was no big difference on eating behavior when feed by-product silage comparing with rice straw. Therefore, it is thought that by-product mixing silage could be the alternative for the rice straw.

• Child Health Nursing Research
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• v.10 no.3
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• pp.251-261
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• 2004

Purpose: To investigate the degree and sources of stress which fathers of infants in NICU experience. Method: Eighty-five fathers of NICU infants at 5 university hospitals in Seoul volunteered to complete the Parental Stressor Scale for NICU (PSS: NICU) from September 1, to October 15, 2002. Result: Total perceived stress was 3.50±0.76. The highest score were in Parental Role Alteration (3.76±0.83) and Appearance and Behavior (3.65±1.04). The total perceived stress score (PSS), correlated significantly with method (t=3.50, p=.01), and route (F=5.30, p=.00) of feeding. Light & Sound correlated significantly with birth weight (F=3.39, p=.02), medical diagnosis(F=2.30, p=.03), plan of operation(t=2.50, p=.01), operation (t=3.80, p=.02), method (F=4.90, p=.003), and route (F=4.70, p=.00) of feeding. Infant Appearance and Behavior correlated significantly with birth weight (F=5.12, p=.01), plan of operation (t=2.50, p=.01), method (F=3.50, p=.01), and route (F=7.80, p=.00) of feeding. Parental Role Alteration correlated significantly with care of incubator (t=-.68, p=.03), method of feeding (F=2.80, p=.04) and education level of father (F=3.00, p=.05). Conclusion: Father with NICU infants were concerned mostly with parental role alteration and infant appearance. Nursing intervention should include fathers of NICU infants.

• Journal of the Korean Dietetic Association
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• v.10 no.3
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• pp.345-355
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• 2004

This study was conducted to investigate the dietary pattern of children with unbalanced diet in school feeding. Children who eat only what they like among elementary school students were selected for this survey. The general characteristics, nutrition knowledge, eating behavior, food intake frequencies and food preferences of the subjects were investigated compared with control group. The subjects were consisted of a total of 160 children : 92 male students(unbalanced-diet group, 46; control group, 46), and 68 female students(unbalanced-diet group, 34; control group, 34). There was no significant difference in nutrition knowledge between the unbalanced-diet group and the control group. Dietary behavior of control group turned out to be more desirable than that of the unbalanced-diet group. In addition, 68.7% of the unbalanced-diet group and 13.8% of the control group hated to eat vegetables. The result of food intake frequency indicates that the control group turned out to be higher in their intake of fish, cereals, vegetables, seaweeds, fats & oils and Kimchi compared with unbalanced-diet group. Intake frequency of minerals and vitamins of the control group was higher than that of the unbalanced-diet group. On the other hand, the unbalanced-diet group turned out to be higher in sugar intake. Children showed the greatest preference of fruits. The unbalanced group turned out to prefer sugar and beverages more than the control group. These results suggest that the desirable dietary habits of children should be formed with the help of nutrition education designed for behavior modification.

• Animal cells and systems
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• v.16 no.5
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• pp.351-356
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• 2012

Food is important to any animal, and a large part of the behavioral repertoire is concerned with ensuring adequate nutrition. Two main nutritional sensations, hunger and satiety, produce opposite behaviors. Hungry animals seek food, increase exploratory behavior and continue feeding once they encounter food. Satiated animals decrease exploratory behavior, take rest, and stop feeding. The signals of hunger or satiety and their effects on physiology and behavior will depend not only on the animal's current nutritional status, but also on its experience and the environment in which the animal evolved. In our novel, nutritionally rich environment, improper control of appetite contributes to diseases from anorexia to the current epidemic of obesity. Despite extraordinary recent advances, genetic contribution to appetite control is still poorly understood partly due to lack of simple genetic model systems. In this review, we will discuss current understanding of molecular and cellular mechanisms by which animals regulate food intake depending on their nutritional status. Then, focusing on relatively less known muscarinic and cGMP signals, we will discuss how the molecular and behavioral aspects of hunger and satiety are conserved in a simple invertebrate model system, Caenorhabditis elegans so as for us to use it to understand the genetics of appetite control.

• The Korean Journal of Pesticide Science
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• v.14 no.2
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• pp.175-182
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• 2010

Two insecticides, fenobucarb (36, 12 ppm) and imidacloprid (0.7, 0.4 ppm) were treated on rice seedling roots by root uptake method with different dipping time (1, 4, 8, 12, 16, 20, 24 hrs). This study was performed to elucidate the correlation between insecticidal activity and feeding behavior of Nilaparvata lugens using EPG (electrical penetration graph). EPG waveforms are recorded for 4 hours and classified into six waveforms. In the correlation between root uptake and corrected mortality, both insecticides showed higher corrected mortality as higher doses and as longer root uptake times. In the analysis of waveforms, N. lugens showed longer nonprobe time but shorter phloem feeding time at a higher dose. It was also showed the same result as longer the root uptake times. Therefore, it showed the correlation between insecticidal activity by root uptake time and both EPG waveforms (non-probing time and phloem feeding time).

• Korean journal of applied entomology
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• v.55 no.4
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• pp.351-358
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• 2016

Consistent with a previous study on the brown planthopper Nilaparvata lugens (BPH) (Seo et al., 2009), we identified seven distinct EPG waveforms (np, L1, L2, L3, L4-a, L4-b, and L5) in adult female Laodelphax striatellus (SBPH) that fed on rice plants, by using the direct current electrical penetration graph (DC-EPG) system. The shape of waveforms and the pattern of occurrence of each waveform of SBPH were very similar to those of BPH. L3 and L4-a always occurred prior to L4-b. Periodical honeydew excretion was observed in L4-b only. Microsection observation following laser stylectomy revealed that the tips of SBPH stylets severed in L3, L4-a, and L4-b were commonly located in or near the phloem region of rice plants, but were located in the xylem in L5. Plant sap flowed from the stylets severed in L4-b only, and its main carbohydrate component was detected as sucrose by HPLC analysis. These results and the patterns of EPG waveform progress in SBPH suggested that feeding activities on rice plant tissue were relevant to each EPG waveform. L1 and L2 corresponded to the initiation of stylet penetration and stylet movement with salivation on the outside of the vascular bundle. L3 and L4-a were related to feeding activities within the phloem region in preparation for phloem sap ingestion. L4-b was closely associated with phloem sap ingestion, and L5 corresponded to xylem feeding behavior.

• Parasites, Hosts and Diseases
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• v.61 no.2
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• pp.172-182
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• 2023

At the time of host attachment, ticks are very sensitive to histamine, but during rapid blood sucking they paradoxically require histamine. Using a rabbit model, we studied the effects of histamine and antihistamine during attachment and fast-feeding in different life stages of Haemaphysalis longicorns. We examined how they responded to histamine and antihistamine by analyzing the detachment rate, histology of feeding lesions, and post-feeding behavior. A significant difference (P<0.01) was found in the detachment rate between experimental and control treatments throughout the observation period. Ticks exhibited a higher detachment rate (30.1%) at 12 h after histamine application during attachment time and on antihistamine-treated skin (25.4%) at 96 h during fast-feeding. After feeding on histamine-treated rabbits, the fully engorged body weights of larvae and nymphs were 0.7±0.36 mg and 3.5±0.65 mg, respectively. An average increase in body weight of 0.6±0.05 mg and 3.2±0.30 mg was observed for larvae and nymphs compared to the respective control weights. Nymphs and adults engorged after antihistamine treatment had an average body weight of 1.3±0.54 mg and 54±0.81 mg, respectively. An average decrease in body weight was observed in antihistamine-treated H. longicornis compared with control nymphs (3.3±0.42 mg) and adults (174±1.78 mg). Skin biopsies were collected after treatment, and differential histopathological characteristics were found between the treatment and control groups. Tick-infested skin collected from rabbits in the antihistamine-treated group lacked erythrocytes in the feeding pool, indicating that antihistamine impaired tick fast-feeding stage.