Number Of Chews Research Articles

Influence of Mastication and Salivation on Swallowing in Stroke Patients

Kim IS, Han TR. Influence of mastication and salivation on swallowing in stroke patients. Objective To determine differences of the oral swallowing functions between stroke and normal subjects and to identify those factors affecting dysphagia of stroke patients. Design Case-control study. Setting University hospital. Participants Ten stroke and 10 healthy subjects. Interventions Not applicable. Main Outcome Measures Resting saliva flow rate, the total number of chews, and the duration of the oral phase until onset of pharyngeal swallow, and food viscosities both before and after the oral phase using diluted barium, pudding, thick rice gruel, and curd type yogurt. Results The viscosity of all test foods was significantly reduced after the oral phase in both groups ( P<.01). Resting saliva flow rate and the viscosity of thick rice gruel after the oral phase in the stroke group were significantly lower than in the control group ( P<.01). However, there were no differences in the viscosities of the other foods between both groups. And a longer oral phase and a greater number of chews prior to pharyngeal swallow were revealed in the stroke group than in the control group ( P<.01). Conclusions This study shows that the food requiring mastication demands a longer oral phase and a greater number of chews, and has more altered rheologic characteristics during the oral phase in stroke patients. These findings suggest that masticatory function is impaired in stroke patients, which may contribute to their swallowing dysfunction.

Effects of physically effective fibre concentration of diets consisting of hay and slowly degradable concentrate on chewing activity in mid lactation dairy cows under constant intake level

Four ruminally cannulated Holstein cows (BW 615 kg) in mid lactation were used to evaluate the effects of fibre level (39, 32, 28, 24 and 19% physically effective NDF [peNDF] in DM) in diets consisting of hay and slowly degradable concentrate on chewing activity, under a constant intake level (18 kg DM · d−1). The different dietary fibre concentrations were achieved by adjusting the hay to concentrate ratio. The above-mentioned levels of peNDF corresponded to 25, 40, 50, 60 and 70% concentrate respectively. The diets with decreasing share of concentrate were offered in sequence according to the progressive lactation of the cows. A decrease of the peNDF from 39 – 28% reduced total chewing and rumination time, total number of chews and number of boluses per day as well as chewing time spent per unit of DM. No significant change in chewing behaviour occurred between peNDF level of 28 and 24%. This peNDF level (i.e., 24%) might be considered as a tolerable fibre level. A further reduction of peNDF to 19% led to a significant reduction of chewing activity. This level can be considered as critical for chewing activity and presumably for the rumen health. The chewing parameters correlated linearly to fibre and non-fibre carbohydrates with R2 of 23 – 51%.

Effects of Physically Effective Fiber on Intake, Chewing Activity, and Ruminal Acidosis for Dairy Cows Fed Diets Based on Corn Silage

A study was conducted to investigate the effects of physically effective (pe) neutral detergent fiber (NDF) content of dairy cow diets containing corn silage as the sole forage type on feed intake, meal patterns, chewing activity, and rumen pH. The experiment was designed as a replicated 3×3 Latin square using 6 lactating dairy cows with ruminal cannulas. Diets were chemically similar but varied in peNDF content (high, medium, and low) by altering corn silage particle length. The physical effectiveness factors for the long (original), medium (rechopped once), and fine (rechopped twice) silages were determined using the Penn State Particle Separator and were 0.84, 0.73, and 0.67, respectively. The peNDF contents of the diets were 11.5, 10.3, and 8.9%, for the high, medium, and low diets, respectively. Increased forage particle length increased intake of peNDF but did not affect intake of DM or NDF. Number of chews (chews/d) and chewing time, including eating and ruminating time, were linearly increased with increasing dietary peNDF. Meal patterns were generally similar for all treatments, except that number of meals was quadratically increased with increasing dietary peNDF. Mean ruminal pH, area between the curve and a horizontal line at pH 5.8 or 5.5, and time that pH was below 5.8 or 5.5 were not affected by peNDF content. Dietary peNDF content was moderately correlated to number of chews during eating (r = 0.41) and to total chewing time (r = 0.37). The present study demonstrates that increasing the peNDF content of diets increased chewing time, but increased chewing time did not necessarily reduce ruminal acidosis. Models that predict rumen pH should include both peNDF and fermentable OM intake. Dietary particle size, expressed as peNDF, was a reliable indicator of chewing activity.

Influence of Bitter Taste on Mastication Pattern

Mastication is a rhythmic activity that can be modified by peripheral information generated in the mouth. To study whether taste cognition could influence the way in which a food is broken down in the mouth, subjects masticated firm, sugar-based gelatine gels with differing concentrations of quinine, up to 1500 micromol/kg, while electromyography (EMG) of masticatory muscles was recorded. Taste intensity and composition of saliva were measured. With increasing quinine concentration, the average number of chews for nine subjects decreased from 30 to 22, and their average clearance time increased from 7 to 14 sec. Quinine concentration had no effect on chewing frequency (1.3 Hz) or on the rate of salivation (5.5 g/min). Bitterness increased, while acceptability and sweetness decreased, with increasing concentration of quinine in the gel and in saliva. Taste cognition could therefore modify food breakdown in the mouth.

Mastication Effort Estimated by Electromyography for Cooked Rice of Differing Water Content

The objective of this study was to quantify the mastication effort for cooked rice. We analyzed mastication patterns while normal subjects ate a spoonful of cooked rice that had been prepared by cooking with different amounts of water (1.5, 2.0, 3.0, and 4.0 times the water to rice weight). The rice samples were served with the same weight, same volume and same solid content, and electromyography (EMG) of the masticatory muscles was measured. The texture of the four cooked rice samples was instrumentally analyzed by the two-bite method. The number of chews, masticatory time, and jaw-closing muscle activities per chew evaluated by EMG were higher in the rice sample cooked with least water, which exhibited a high firmness value in the instrumental test. Rice cooked with 4.0 times the amount of water exhibited the longest jaw-opening duration, which was related to the adhesiveness value in the instrumental test. The ratio of jaw-opening muscle activity to the preceding jaw-closing muscle activity was lower for the rice containing least water, this corresponding to the area ratio (balance degree) in the instrumental test. Softer rice containing more water reduced the total mastication effort until swallowing because it required a shorter mastication time. It was not difficult for the softer rice with high density to be ingested in greater weight, decreasing the mastication effort for a certain amount.

自由そしゃくと片側そしゃくの機能的差異の検討

Unilateral chewing requires a greater number of chewing strokes up to the point of the first swallowing. The rate of storage of ground food particles in the oral vestibule is said to be high during unilateral chewing. However, influence of the masticatory method, that is free-sided or unilateral chewing, involved in masticatory efficiency has not been elucidated. On that point, in order to clearly represent the effects that free-sided (bilateral) chewing and unilateral chewing have on the chewing efficiency, our purpose was to examine the difference of the functions of both free-sided chewing and unilateral chewing. We used 116 dentate subjects with normal occlusal relations, and compared the number of chewing strokes for peanuts up to the point of the first swallowing (abbreviated as "chewing strokes") for both free-sided chewing and unilateral chewing. Following this, we made calculations regarding the amount of saliva secretion, occlusal force, and contact points of posterior teeth. Based on the averages of three parameters (saliva secretion, occlusal force and contact points of posterior teeth), all the subjects were classified into two groups (high score group and low score group). In the two groups, we counted the difference in the number of free-sided chewing and unilateral chewing. And also in two groups, the amount of remaining coarse particles immediately prior to the first swallowing was investigated between free-sided chewing and unilateral chewing. The number of chewing strokes by free-sided chewing for all subjects was 10% less than that of unilateral chewing. Furthermore, the numbers of chewing strokes by free-sided chewing were all less than those of unilateral chewing in both groups on three parameters. The amount of remaining coarse particles by free-sided chewing was significantly smaller than that of unilateral chewing in the low score group of saliva secretion and occlusal force. The number of chewing strokes by free-sided chewing was less than that of unilateral chewing in both of the high score group and low score group on the amount of saliva secretion, occlusal force, and contact points of posterior teeth.

The Effect of Bilateral Lingual Nerve Anesthesia and Increased Occlusal Vertical Dimension on the Onset of Swallowing in Adult Males

The present study attempts to determine whether the onset of swallowing is affected by bilateral lingual and inferior alveolar nerve anesthesia and by raising the occlusal vertical dimension by wearing an occlusal bite plate. Twenty young male volunteers were selected and asked to chew and swallow corned beef and a corned beef and liquid mixture in their usual manner before and after modifications were made. Oral and pharyngeal swallowing was investigated using videofluoroscopic examination in the lateral plane. Eight objective indicators, including oral containment time, swallowing threshold, and pharynx-to-swallow intervals were estimated. Oral containment time, total sequence duration, total number of chews, and total number of swallows of the two test foods were significantly different before and after the modifications. Individual pharynx-to-swallow intervals also varied. The results indicate that modification of the masticatory condition affects the onset of swallowing and that changes in the onset varied among the participants.

Sensory Texture and Mechanical Properties of Stranded and Particulate Whey Protein Emulsion Gels

ABSTRACT: The influence of gel structure type and amount of lipid on texture of whey protein isolate (WPI) gels was evaluated by descriptive sensory analysis and determination of fracture and water‐holding properties. A series of 16 gels of varying structure (particulate or stranded) and lipid composition (0% to 20%) were developed at a constant protein concentration (12% w/v). Stranded gels had higher values for fracture strain, strain hardening, and held‐water. Particulate and stranded gels were similar in fracture stress. Eighteen sensory texture attributes were used to evaluate gels throughout the mastication process that was separated by the following phases: prefracture, 1st bite, chew‐down, and preswallowing. The 1st bite property of firmness and preswallowing properties of number of chews and time to swallow were the only sensory properties associated with lipid content. Fracture stress was correlated with these properties. The remaining 15 texture terms were primarily determined by gel structure type. It appears that gel structure type determines the primary texture properties of WPI emulsion gels. An increase in lipid content increases gel firmness and amount of chews required; however, it did not change the primary texture sensation.

Effects of bilateral lingual and inferior alveolar nerve anesthesia effects on masticatory function and early swallowing.

To determine whether bilateral lingual and inferior alveolar nerve anesthesia affects the onset of swallowing including masticatory function. Twenty young male volunteers were asked to chew and swallow corned beef and then a mixture of corned beef and liquid in their usual manner before and after local anesthesia. The oral and pharyngeal swallowing was investigated using videofluoroscopic examination in a lateral plane. Eight objective indicators including oral containment time, swallowing threshold, and pharynx-to-swallow interval were measured. Oral containment time and total sequence duration, total number of chews, and total number of swallows for the 2 test foods varied significantly between those before and after anesthesia. Individual pharynx-to-swallow intervals varied with both foods without remarkable increases or decreases in the swallow duration and cricopharyngeal opening time. Bilateral lingual and inferior alveolar nerve anesthesia may affect early swallowing; changes in the onset of swallowing varied among the participants.

Effects of bilateral lingual and inferior alveolar nerve anesthesia effects on masticatory function and early swallowing

Objective To determine whether bilateral lingual and inferior alveolar nerve anesthesia affects the onset of swallowing including masticatory function. Study design Twenty young male volunteers were asked to chew and swallow corned beef and then a mixture of corned beef and liquid in their usual manner before and after local anesthesia. The oral and pharyngeal swallowing was investigated using videofluoroscopic examination in a lateral plane. Eight objective indicators including oral containment time, swallowing threshold, and pharynx-to-swallow interval were measured. Results Oral containment time and total sequence duration, total number of chews, and total number of swallows for the 2 test foods varied significantly between those before and after anesthesia. Individual pharynx-to-swallow intervals varied with both foods without remarkable increases or decreases in the swallow duration and cricopharyngeal opening time. Conclusion Bilateral lingual and inferior alveolar nerve anesthesia may affect early swallowing; changes in the onset of swallowing varied among the participants.

볏짚 및 가공처리 왕겨의 급여가 한우의 사료섭취 및 반추행동에 미치는 영향

본 연구는 한우에 급여하는 저질 조사료 원 이 반추시간 및 빈도, 저작시간 및 저작빈도에 미치는 효과를 알아보기 위해 실시하였다. 시험사료는 농후사료 + 볏짚(50:50), 농후사료 + 볏짚 + 팽연왕겨(50:35:15), 농후사료+ 볏짚 + 분쇄왕겨(50:35:15)을 사용하였다. 농후사료 + 볏짚(50:50), 농후사료+ 볏짚 + 팽연왕겨(50:35:15) 및 농후사료+ 볏짚+분쇄왕겨(50:35:15)를 섭취한 한우의 사료섭취 및 반추시간은 각각 78.8과 338.4, 98.0과 362.5, 그리고 160과 519.2minld이었다. 벗짚의 30%를 팽연왕겨나 분쇄왕겨로 대체하였올 때 사료섭취 및 반추시간이 유의하게 증가하였으며 (p<0.05), 1일 반추시 총 저작횟수와 본당 저작횟수는 팽연왕겨와 분쇄왕겨를 급여하였올 때 유의하게 감소하였다(p<0.05). 또한 일일 총 반추식괴수와 반추분당 식괴수도 팽연왕겨와 분쇄왕겨를 급여할 때에 감소되었지만, 식괴당 저작시간과 저작횟수는 증가되었다(p<0.05). 이러한 결과는 볏짚과는 다른 물리척 폭성을 행연왕겨와 분쇄왕겨가 갖고 있고, 왕겨의 조사료적인 가치는 왕겨가 갖고 있는 물리척인 유효성에 의하여 반추위가 자극펀 결과에 의한 것으로 생각된다. Effects of low quality roughage sources on duration and frequencies of rumination and chewing in Hanwoo steers were determined, Animals were fed three diets; concentrate+rice straw(SO:SO), concentrate+ rice straw + popped rice hull(SO:3S: IS) and concentrate+ rice straw+ground rice hull(SO:3S: IS) to compare both rice straw alone and combination with rice hull. Eating and ruminating time of steers fed concentrate+ rice straw(SO:50), concentrate+ rice straw + popped rice hull(50:35:15) and concentrate + rice straw + ground rice hull(50:3S:15) were 78.8 and 338.4minlday; 98.0 and 362.5minlday, and 160 and 519.2min/day, respectively. When steers were fed popped rice hull and ground rice hull, time spent for both eating and ruminating was significantly increased(p <0.05). When steers fed popped and ground rice hull, number of ruminating chews and number of chews per rumination time were significantly decreased(p<0.05). The number of rumination boli and boli per rumination time had significantly decreased(p<0.05), but chewing time per boli, number of chew'S per bolus were significantly increased(p <O.OS) in steers fed both types of rice hull. In summary, when cattle were fed experimental diets substituted with popped or ground rice hull to rice straw, the rumination behaviors were increased, because popped or ground rice hull might physically stimulate rumen wall. Therefore, both the physically shape and size of roughage sources are important factors to induce rumination behavior.

농후사료와 조사료의 비율이 한우의 저작 및 반추시간과 빈도에 미치는 영향

농후사료와 조사료의 비율이 한우의 반추행동, 저작시간 및 저작빈도에 미치는 효과를 조사하기 위하여, 반추위 누관이 장착되고, 턱 주위에 트랜스듀서가 설치된 한우 성우 5두를 공시하였다. 사료는 농후사료와 볏짚의 급여비율을 50 : 50, 60 : 40, 70 : 30, 80 : 20과 90 : 10으로 급여하면서 사료섭취와 반추행동의 변화를 조사하였다. 사료 중 조사료의 비율을 전체 건물량의 10, 20, 30, 40과 50%로 증가시켰으F 때 일일 총 저작시간은 286.99분에서 423.30분/일로 직선적으로 증가하였는데, 이것은 반추시간이 204.91에서 342.80분/일로 증가한 것에 주로 기인하였다. 그러나 농후사료의 급여수준에 따른 사료 섭취 시간의 차이는 없었으며, 일일 반추시 저작횟수와 반추당 저작횟수는 농후사료의 급여 비율의 증가에 의하여 감소되었다. The effects of concentrate to roughage ratios on duration and frequencies of rumination and chewing in Hanwoo steers were determined. Five Hanwoo steers fitted with rumen fistula were used to evaluate the effects of concentrate to rice straw ratio on eating and ruminating behavior. Experimental diets were formulated with different concentrate to rice straw ratios(50 : 50, 60: 40, 70: 30, 80: 20, 90: 10). When level of roughage feed was increased by 10, 20, 30, 40 to 50% of total dry matter of the diet, total chewing time was increased linearly from 286.99, 321.09, 390.29, 406.63 to 423.30 min/d, which was mainly due to increased ruminating time from 204.91 to 342.80 min/day. However, the level of roughage did not affect eating time. The number of chews per day for rumination and number of chews per rumination were significantly decreased(p < 0.05) as roughage level was increased. In summary, the duration and frequencies of rumination in Hanwoo increased with increased rice straw level.

Fattening performance, carcass traits and meat quality characteristics of calves sired by Charolais, Simmental and Eastern Anatolian Red sires mated to Eastern Anatolian Red dams

Comparisons were made among calves sired by Charolais (C), Simmental (S) and Eastern Anatolian Red (EAR) breeds of bulls for fattening, carcass and meat quality traits when mated to EAR dams. C- and S-sired calves had 43.1% and 36.4% higher daily weight gain, 44.5% and 43.9% heavier final weight in fattening, respectively. Calves produced by C sires had best feed efficiency value (6.51 vs. 7.44 and 7.22) compared to the S and EAR sire breed groups. Carcasses of C- and S-sired calves had heavier weight, higher dressing percentage and greater Longissimus dorsi (LD) muscle area than those of EAR-sired calves. USDA yield grades were lower ( P<0.01) for carcasses from C and S sires, and highest for carcasses from EAR calves. C-sired calves received higher ( P<0.01) ratings for panel tenderness score, lower shear force value and number of chews before swallow than S- and EAR-sired progeny. Overall results of the study suggested that fattening performance, carcass and meat quality characteristics might be considerably improved by using C sires in the crossbreeding program as sire breed.

Temporal aspects of feeding events in tammar (Macropus eugenii) and parma (Macropus parma) wallabies. I. Food acquisition and oral processing

We studied parameters that influence the efficiency of food acquisition and oral processing in the tammar wallaby (a grazer) and the parma wallaby (a grazer/browser), both in captivity and under free range on Kawau Island, New Zealand.In captivity, both species spent less time feeding per gram of dry matter intake when browsing than when grazing, and there were no significant differences between the species with respect to the rates of feeding per gram of dry matter intake of a given food. However, under free-ranging conditions, tammar wallabies spent longer feeding than did parma wallabies, so it was likely that tammar wallabies spent more time grazing than browsing. Differences in the relationships between feeding event and inter-feed interval duration in captive and free-ranging wallabies indicated that feeding behaviour was influenced by different factors in the two situations.Microtemporal analysis of the chewing sounds of free-ranging tammar and parma wallabies showed that the interval between the first and second sounds in a 'run' of chewing sounds was longer than that between subsequent intervals, indicating that there was a time cost associated with food aquisition. However, as there were no significant differences between the two wallaby species, either in the mean duration of 'runs' of chewing sounds within feeding events or in the mean duration of whole feeding events, this cost was similar for grazing and browsing. Chewing characteristics differed from those of larger (eutherian) herbivores in that the numbers of chews in a run were not randomly distributed, both species having a preponderance of runs with seven chews. Whilst, the intervals between the second and subsequent chewing sounds in a run did not vary in a periodic manner, such as would occur in batch processing of food, they were more prolonged in runs with more chewing sounds and were significantly longer in tammar wallabies than in parma wallabies. Thus, the slower rate of oral processing of grass was likely due to a generally slower rate of chewing when grazing than when browsing.

The effect of pellet texture on the feeding behaviour of gilthead sea bream ( Sparus aurata L.)

The aim of this study was to investigate the behaviour of gilthead sea bream when fed control and soft-textured pellets, to determine whether the immediate feeding response to a softer pellet resulted in less manipulation of the pellets during feeding, increased consumption, and reduced waste from handling. Individual feed intakes were calculated from radiographs and the proportion of unaccounted ballotini beads used to estimate waste production from chewing. The proportion of feed particles to unbroken pellets in the stomach was also measured. Food handling behaviour (chewing rate, number of bream chewing, and ejecting pellets) was recorded using an underwater camera. When fed the soft-textured pellets, a greater proportion of feed particles in the stomach was found in comparison to when the control diet was fed ( P<0.001). This implies that sea bream crush softer pellets more effectively. This was further supported by the soft-textured diet eliciting a lower rate of chewing ( P=0.001). There was a trend for the proportion of feed particles extracted from the stomachs of bream fed on the control diet to increase over time ( P=0.001), resulting in the difference in the proportion of feed particles in the stomachs between diets lacking significance in the final sample days. This may be related to either increasing body size and development of dentition resulting in greater crushing power or the bream may have learnt over time to crush the pellets more effectively. The results suggest that bream can crush softer pellets more effectively, but with no impact on waste production or feed intake. The results are discussed in relation to the design of pellets to optimise production efficiency, product development, and waste reduction in sea bream aquaculture.

DESCRIPTIVE ANALYSIS OF CARAMEL TEXTURE1

ABSTRACTOral sensory evaluation of caramel texture was conducted using six texture terms and results were compared to instrumental testing of texture. Trained panelists (n = 11) evaluated 6 caramel formulations by descriptive analysis. Mean texture values indicated that a slight increase in sweetened condensed skim milk and vegetable fat content (1% w/w at a 2:1 ratio) significantly decreased stickiness (P≤ 0.05). Decreasing corn syrup dextrose equivalent (DE) decreased stickiness and increased hardness (P≤ 0.05). Pearson correlation coefficients revealed that stickiness to teeth while chewing, toothpacking, and tooth adhesiveness were highly correlated with one another (P≤ 0.05). Sensory hardness, cohesiveness, and number of chews were correlated with the rheological properties of storage modulus and viscosity, while stickiness was correlated with probe tack force (P≤ 0.05). Such correlations show that fundamental rheological and tack force measurements can be used to help determine molecular mechanisms for sensory texture and stickiness.

Study on the Number of Chews by Preschool Children

Study on the Number of Chews by Preschool Children

Eating behavior of Ongole crossbred and Limousin crossbred steers fed fermented rice straw and concentrate

A study on eating behavior of Ongole Crossbred (OC) and Limousin Crossbred (LC) steers (aged 9 months) fed fermented rice straw and concentrate has been carried out. Rice straw and concentrate were given in 60:40 ratio. Rice straw was fermented by commercial starter (BioP 2000 Z), while concentrate was composed of commercial concentrate and soybean pulp (by-product of soy-sauce industry). The diet was set to meet the dry matter (DM) requirement at 3.0% of liveweight. Eating behaviour was measured from 3 days continuously observation. Chewing number was accounted by halter equipped with tape-switch in jaw side and was recorded every 1/10 second in connected PC. The results showed that DMI of both OC (3.21 kg) and LC (4.18 kg) was similar, being 2.8% LW. However, chewing number of OC (133808 chews/d) was higher than that of LC (106353 chews/d). Chewing for eating and for rumination in OC (86995 and 46813 chews) was higher than of LC (67628 and 38725 chews). Chewing efficiency for eating in OC (0.041 g DMI/chew) was lower than that of LC (0.066 g DMI/chew). Similar tendency was observed in chewing efficiency for rumination that OC (0.080 g DMI/chew) was lower than that of LC (0.109 g DMI/chew). The conclusion is LC has a better chewing efficiency than of OC and it was pointed to different jaw size between OC and LC. Key words: Chewing, Ongole, Limousin

The influence of orthodontics on selection and breakage underlying food comminution in pre-orthognathic surgery patients

Comminution of food is the composite result of selection and breakage. Selection is characterized by the chance that a food particle will at least be damaged by the teeth during a chew. For any particle size, this chance equals the ratio between the weight of damaged and broken particles and that of all initial particles. The breakage process refers to fracturing of selected particles. Since orthodontic treatment applied to patients before orthognathic surgery has an effect on the position and orientation of teeth, it may alter chewing efficiency by influencing selection and/or breakage. The effect of such orthodontic treatment on chewing efficiency was examined using eight cubes of 8.0mm of a silicone-rubber (Optosil®) as a test food for determining the number of chews required to halve the initial particle size (N1/2) in 12 patients. Three particle sizes (2.4, 4.8 and 8.0mm) were used for determining selection and breakage in one-chew experiments. Orthodontic treatment had no effect on the chewing efficiency and the selection chances of all particle sizes whereas the degree of breakage was significantly (P< 0.05) increased only for a particle size of 8.0mm. These findings suggest that presurgical orthodontics has only a minor effect on food comminution.

Comparison of SLN-evoked swallows during rest and chewing in the freely behaving rabbit

Interactions between the swallowing central neural pathway and the chewing central neural pathway were examined in freely behaving, unanesthetized rabbits. Pharyngeal swallows were elicited by electrical stimulation of the superior laryngeal nerve (SLN) and defined by thyrohyoid muscle (TH) activity in the electromyogram (EMG). Recordings were obtained from rabbits at rest and during chewing. The number of swallows elicited by the SLN stimulation was significantly increased ( P<0.001) during quiet oral function (at rest) and during chewing. The increased number of swallows from each baseline was similar, signifying that the effect of the SLN stimulation was similar in generating swallowing in both groups. The swallows induced with SLN stimulation were very similar to natural swallows as defined by the temporal pattern of the EMG duration and the timing of EMG activities. Our results suggest that: (1) the peripheral inputs to the swallowing pathway may rarely be modulated by the chewing pathway in the generation of swallows; (2) the swallowing pathway and the chewing pathway may interact at the level of the rhythm generators; (3) each animal has its own threshold for eliciting pharyngeal swallowing, and the threshold may be independent of the number of chews.