绵羊犁鼻器在繁殖中的作用

许多动物的尿液中含有重要的外激素信息,其生理意义多种多样。雌性尿液中多有表示本身性别及性状况的化学信息存在,行为学调查表明,犁鼻器的主要功能在于识别尿液气味。公羊正是依据这些化学信息识别并选择配偶的。通常公羊嗅到母羊,尤其是发情母羊尿液时,表现伸颈、抬头、卷缩上唇的特有行为型式,称之为卷唇行为或性嗅反射。这个行为是与犁鼻器的功能相联系的。它的作用在于关闭外鼻孔,堵闭会厌,使吸进的空气进入犁鼻器内,犁鼻器两侧的肌肉运动,腔内静脉窦的膨胀和收缩,又促进空气的流入和排出,如此使携带化学信息的载体不断进入犁鼻器官,成为绵羊感受化学信息的方式之一。 犁鼻器的作用可为公羊及早地、准确地选择发情的配偶提供信息;同时又能唤起公羊本身的性行为,刺激雌、雄发情及性活动的同步,对保证繁殖的成功具有一定的意义。说明绵羊犁鼻器作为化学感受器在化学通讯中特别是对繁殖行为具有重要作用。     

Videofluorographic analysis of tongue movement in the rabbit (Oryctolagus cuniculus)

The movement of the entire tongue and intermolar eminence during mastication is described in the domestic rabbit (Oryctolagus cuniculus). Tongue movement and jaw position were analyzed videofluorographically from separate lateral and dorso-ventral views in six rabbits. Metallic markers were inserted into the tongue so that its movement was visible on the fluorographic image. Frame-by-frame analysis of the videofluorographic tape recordings demonstrates that tongue movement in all animals was identical in direction during each part of the chewing cycle. In the lateral view the forepart of the tongue moves down and forward during the opening stroke, whereas the intermolar eminence moves up and forward to appose the palate. During the closing stroke, as the tip of the tongue moves up and back, the intermolar eminence lowers from the palate and retracts. During the power stroke the forepart of the tongue is at its most elevated and retruded position, while the intermolar eminence is its lowest and most retruded. The dorso-ventral view showed that lateral movement of the tongue and mandible are highly synchronous. The intermolar eminence decreases in width during the power stroke, possibly twisting to place or keep food on the teeth. An anterior to posterior undulating movement of the entire tongue occurs throughout the chewing cycle. As the intermolar eminence elevates to appose the palate during the opening stroke, it may replace the bolus on the teeth on the chewing side. The intermolar eminence also appears to be twisting during the closing and power strokes to place or maintain food on the teeth.     

Electromyographic analysis of the superior belly of the omohyoid muscle and anterior belly of the digastric muscle in tongue and head movements.

The participation of the superior belly of the omohyoid muscle and anterior belly of the digastric muscle in tongue and head movements was studied eletromyographically in 20 normal young volunteers. A pair of monopolar electrodes was used in each muscle for simultaneous recording of their actions. The muscles act in the following tongue movements: protrusion, right and left lateral movements, placement of the tip of the tongue on soft and hard palates and on the floor of the mouth. The strongest levels of activity of the superior belly of the omohyoid muscle were observed in the placement of the tip of the tongue on the soft palate, coincidentally with a greater dislocation of hyoid bone. Both of the muscles studied did not participate in the head's kinesiology.     

Comparative anatomic studies of the vomeronasal complex and the rostral palate of various mammals

The structures of the rostral palate in regard to the vomeronasal complex of different species of mammals were studied. In all cases, we find a very interesting system of furrows which preserves a connection between the nasopalatine ducts and the preoral surroundings. For rodents, lagomorphs, Solenodon, Setifer, and Echinops, we find a special situation in this part of the palate. Here the incisors are not separated by a diastema nor the oral openings of the nasopalatine ducts are overgrown by a bipartite caudal branch of the rhinarium. The results of the anatomic studies of the vomeronasal complex and the rostral palate of the mammals investigated are discussed: First of all, some elements of the vomeronasal complex needed to be analysed in regard to structure and nomenclature, specifically the cartilago paraseptalis with its outer bar, the cartilago ductus nasopalatini and the cartilago palatina. Because of 2 criterions, the vomeronasal complex could be classified as either primitive or progressive. We find a primitive one in Didelphis, Tupaia, Solenodon, Oryctolagus, and all rodents. In contrast, the other insectivores studied and all primates show progressive structures at their vomeronasal complex. Finally, conclusions in regard to the function of the organs of Jacobson are derived from these studies. The significance of the "flehmen" mechanism for the functioning of the organs is questioned.     

Stimulus and hormonal determinants of flehmen behavior in cats

Felids are the main group of animals, other than ungulates, that display flehmen behavior during sociosexual interactions. In ungulates the behavior is evoked most readily by olfactory investigation of urine and vaginal secretions, and is believed to be involved in the transport of fluid-borne chemical stimuli, such as sex pheromones, from the oral cavity to the vomeronasal organ. In this study of cats flehmen was virtually always preceded by nasooral contact with the stimulus material, supporting the notion that flehmen in this species is also involved in the transport of fluid-borne stimuli. As in ungulates, flehmen in cats during heterosexual encounters was found to be displayed by males only. However, the sexual dimorphism was situation specific. In exploring a urine-marked room without another cat present, females also performed flehmen, albeit less frequently than males, and when urine was applied to the nasooral surface, flehmen was evoked equally reliably in females and males. Administration of testosterone propionate to spayed female cats paired with estrogen-treated females markedly increased their tendency to genitally inspect the female partner and subsequently perform flehmen. Thus the sexually dimorphic attributes of flehmen behavior are not only stimulus dependent, but also influenced by concurrent hormone stimulation.     

Differential sensitivity of tongue areas and palate to electrical stimulation: a suprathreshold cross-modal matching study

A cross-modal matching procedure was used, in twelve subjects,to evaluate regional differences in suprathreshold sensitivityof the oral cavity to electrogustometric stimulation. Stimulationof five loci on each side of the oral cavity was performed:tongue tip (one cm from the midline), anterior tongue side (2.5cm from tip on lateral margin), posterior tongue side (regionof the foliate papillae), posterior medial tongue (one cm frommidline on circumvallate papillae), and soft palate (one cmfrom midline, one cm above superior pole of anterior palatinearch). The tip of the tongue was significantly more sensitivethan the other areas to electric stimulation, as evidenced bythe slope and absolute position of the psychophysical powerfunctions. Strong correlations were observed in the sensitivitymeasures across tongue loci and between tongue and palate sides.No effects of subject gender or mouth side were found.     

The ontogeny of flehmen in horses

Flehmen behaviour in Welsh pony (Equus caballus) mares and foals living on pasture was observed during 807 h of focal sampling. A series of flehmens performed at one site was defined as a flehmen incident. Colts exhibited flehmen incidents and performed flehmen more frequently during an incident than did fillies or mares. Filies exhibited flehmen incidents more frequently than did mares, but did not flehmen more frequently during an incident. Colts exhibited a peak frequency of performing flehmen and of flehmen incidents during weeks 1–4 with a subsequent linear decrease in frequency up to weeks 17–20. Usually, flehmen occurred without the subject having had direct contact of the nostrils, lips, or tongue with a possible stimulant. Twenty-six per cent of the flehmen incidents occurred during or after urination by another pony. Seven per cent of the incidents occurred during or after urination by the pony showing flehmen.     

Ontogeny of Flehmen in Sable Antelope,Hippotragus niger

Flehmen, a conspicuous posture characterized by eversion of the upper lip, facilitates the transfer of nonvolatile urinary chemicals to the vomeronasal organ and therefore has been implicated in the control of reproduction in ungulates. The ontogeny of urine sampling and flehmen was investigated in semi-free-ranging sable antelope, Hippotragus niger, at the National Zoological Park's Conservation and Research Center because behavioural evidence suggests that flehmen is a mechanism of reproductive synchronization among females. During the first year of life, flehmen rates increased with age in both sexes. Flehmen rates of female calves equalled those of adult females by 4 months of age. Male calves first exhibited flehmen at younger ages than did female calves and showed greater increases in flehmen rate during development. Both sexes exhibited flehmen primarily after sampling urine of female conspecifics as it was being voided. During the first 2 months of life, sable antelope preferred to sample urine of other calves, but by 1 year of age adult females were the preferred targets. Females approaching sexual maturity preferred to sample urine from postpartum females (presumably resuming oestrous cycling) rather than from pregnant females, as expected if they were attempting to synchronize oestrus with experienced females. Results are consistent with the hypothesis that flehmen serves to coordinate reproduction among females and further suggest that flehmen may affect reproductive maturation.     

The mechanism of chemical delivery to the vomeronasal organs in squamate reptiles: a comparative morphological approach

Vomeronasal chemoreception, an important chemical sense in squamate reptiles (lizards and snakes), is mediated by paired vomeronasal organs (VNOs), which are only accessible via ducts opening through the palate anteriorly. We comparatively examined the morphology of the oral cavity in lizards with unforked tongues to elucidate the mechanism of stage I delivery (transport of chemical-laden fluid from the tongue tips to the VNO fenestrae) and to test the generality of the Gillingham and Clark (1981. Can J Zool 59:1651-1657) hypothesis (based on derived snakes), which suggests that the sublingual plicae act as the direct conveyors of chemicals to the VNOs. At rest, the foretongue lies within a chamber formed by the sublingual plicae ventrally and the palate dorsally, with little or no space around the anterior foretongue when the mouth is closed. There is a remarkable conformity between the shape of this chamber and the shape of the foretongue. We propose a hydraulic mechanism for stage I chemical transport in squamates: during mouth closure, the compliant tongue is compressed within this cavity and the floor of the mouth is elevated, expressing fluid from the sublingual glands within the plicae. Chemical-laden fluid covering the tongue tips is forced dorsally and posteriorly toward the VNO fenestrae. In effect, the tongue acts as a piston, pressurizing the fluid surrounding the foretongue so that chemical transport to the VNO ducts is effected almost instantaneously. Our findings falsify the Gillingham and Clark (1981. Can J Zool 59:1651-1657) hypothesis for lizards lacking forked, retractile tongues.     

Enhanced extrinsic innervation of nasal and oral chemosensory mucosae in keratin 14-NGF transgenic mice

The role of nerve growth factor (NGF) in neurotrophic support for the extrinsic innervation of the nasal and oral mucosae was investigated in keratin 14 (K14)-NGF transgenic mice in which NGF was over-expressed in K14-synthesizing cells. K14 immunoreactivity was localized in the epithelial basal cells of the whisker pad skin, the hard palate, the floor of the ventral meatus, and the anterior tongue that are stratified squamous epithelia, and also in basal cells of the vomeronasal, olfactory, and respiratory epithelia that are non-stratified epithelia. In transgenic mice, NGF expression was identified and confined primarily to the basal cells of stratified epithelia. The nasal mucosae including the vomeronasal, olfactory, and respiratory mucosae, and the glands associated with the vomeronasal organ received a greater innervation of protein gene product 9.5-immunoreactive extrinsic fibers in transgenic animals than nontransgenic controls. An increased density of calcitonin gene-related peptide-immunoreactive extrinsic fibers was observed in the nonsensory epithelia of the vomeronasal organ, the olfactory sensory and respiratory epithelia in transgenic animals. Our results indicated that the hyperinnervation of the nasal and oral mucosae by extrinsic neurons is due at least partially to target-derived NGF synthesis and release by K14-expressing basal cells.This work was supported by NIH grants NIDCD-00159 (T.V.G.), NIDCO-01715 (M.L.G.), and NINDS-31826 (K.M.A.).     

Appearance of entodermal antigen in the mouth mucosa of dogs in recurrent spontaneous stomatitis]

An additional component absent in the same areas of the mouth under normal conditions appeared in dogs with spontaneous stomatitis in the ectodermal derivatives (mucosa of the cheeks, tongue and the hard palate). This component proved to be fully identical to the antigens of the mucosa of the soft palate, esophagus, stomach, small and large intestine, which were entodermal derivatives. No entodermal antigen was revealed in the other organs and tissues under study.     

Palatal schwannoma in an elderly woman

Schwannoma also known as neurilemmoma is a benign tumour derived from schwann cells and is relatively rare in occurrence. Only 1% of the schwannomas in the head and neck region occur at intra-oral sites. Schwannomas usually occur during the third or fourth decades of life and the tongue is the most common intra-oral site. A case of intra-oral schwannoma in a 70-year-old female in the region of hard palate is described which is extremely rare.     

绵羊的卷唇行为及其生物学意义

本文研究了绵羊对不同品种公母羊的尿液、母羊粪便、阴道分泌物、身体的气味等刺激物诱导卷唇行为的发生,持续约60-120秒。实验得出:母羊尿液是诱导公羊释放卷唇行为最强的刺激物,尤以发情母羊尿液更甚,公羊、幼羊以及其它的尿液诱导卷唇行为发生的频次低。卷唇行为发生的频次有季节变化,10月最高。卷唇行为与犁鼻器的功能紧密联系,是绵羊繁殖行为的一个构成部分,通常只有公羊发生卷唇行为,但个别母羊亦有表现。     

Functional hemitongue reconstruction with the microvascular ulnar forearm flap.

Thirteen patients with squamous cell carcinoma of the tongue underwent full-thickness longitudinal resection of the hemitongue and immediate microvascular reconstruction using a large, contoured ulnar forearm flap. Six of the 13 patients had a composite resection for which an additional vascularized iliac crest graft was used to reconstruct the mandible and to provide support to the overlying contoured flap. To increase tongue mobility, the skin flap was designed for independent reconstruction of the hemitongue and the floor of mouth. Twelve patients were evaluated for swallowing and speech, including dietary assessment, cineradiography, and voice spectrographic analysis. Contrast cineradiography was performed to determine oral tongue mobility during the first phase of swallow. Nine patients with a narrow reconstructed tongue root and a large surface area in the floor of the mouth had good tongue mobility, allowing them to transfer food dynamically from the mouth into the pharynx for swallowing. The remaining three patients, who had a wide tongue root and an ill-defined floor of the mouth, had decreased tongue mobility and poor oral transport. The functional outcome of swallowing and speech strongly correlated with the shape of the root of the tongue, the proximity of the reconstructed tongue to the palate, and the surface area of the floor of the mouth.     

Total and subtotal glossectomy: function after microvascular reconstruction

Twelve patients with advanced carcinoma of the floor of the mouth and tongue were treated with total (five patients) or subtotal (seven patients) glossectomy, partial mandibulectomy, and immediate reconstruction with the microvascular composite groin flap. The osteomusculocutaneous groin flap was used in eleven patients, and the osteomuscular flap was used in one patient. The groin musculocutaneous or muscle flap was designed to resemble the shape of the tongue for dynamic food transport, improved swallowing, and acceptable speech. Eight of the 12 patients who survived more than 1 year were evaluated for speech and swallowing. Eight patients were able to speak intelligibly, six patients could tolerate a soft/pureed diet, and two patients were limited to fluids. Cinefluorographic swallow studies using semisolid contrast material showed voluntary active intraoral transport and propulsive pharyngeal emptying without aspiration in six patients with complete flap to palate contact; the remaining two patients were unable to move the intraoral contrast material effectively for swallowing because of poor palatal contact.     

Comparison of surface electromyographic (sEMG) activity of submental muscles between the head lift and tongue press exercises as a therapeutic exercise for pharyngeal dysphagia

Objective: The present study compared surface electromyographic (sEMG) activity obtained from the submental muscle group for a tongue press and a head lift exercise as potential therapeutic exercises for dysphagic elderly. Materials and methods: Fifty‐three healthy volunteers with a mean age of 35.3 participated in this study. Subjects were required to perform an isometric task, pressing their tongue against the hard palate, and an isotonic task requiring sustained lingual force against the hard palate. Pressure sensors were used to measure the amount of lingual pressure against the hard palate. Submental sEMG data from these tasks were compared with those obtained from the isometric and isotonic aspects of a head lift exercise. Results: No sEMG differences were identified between the isometric tongue press task and head lift exercise. Isotonic tongue press exercises resulted in significantly higher maximum and mean sEMG values compared with the isotonic head lift exercise (p < 0.05). The submental sEMG activity from the tongue press exercise was equal (isometric) to, or greater (isotonic) than comparable muscle activation obtained during the head lift exercise. Conclusions: The tongue press exercise may be less strenuous than the head lift exercise while achieving the same therapeutic effect.     

Olfactory metamorphosis in the Coastal Giant Salamander (Dicamptodon tenebrosus)

This study examined the gross morphology and ultrastructure of the olfactory organ of larvae, neotenic adults, and terrestrial adults of the Coastal Giant Salamander (Dicamptodon tenebrosus). The olfactory organ of all aquatic animals (larvae and neotenes) is similar in structure, forming a tube extending from the external naris to the choana. A nonsensory vestibule leads into the main olfactory cavity. The epithelium of the main olfactory cavity is thrown into a series of transverse valleys and ridges, with at least six dorsal and nine ventral valleys lined with olfactory epithelium, and separated by ridges of respiratory epithelium. The ridges enlarge with growth, forming large flaps extending into the lumen in neotenes. The vomeronasal organ is a diverticulum off the ventrolateral side of the main olfactory cavity. In terrestrial animals, by contrast, the vestibule has been lost. The main olfactory cavity has become much broader and dorsoventrally compressed. The prominent transverse ridges are lost, although small diagonal ridges of respiratory epithelium are found in the lateral region of the ventral olfactory epithelium. The posterior and posteromedial wall of the main olfactory cavity is composed of respiratory epithelium, in contrast to the olfactory epithelium found here in aquatic forms. The vomeronasal organ remains similar to that in large larvae, but is now connected to the mouth by a groove that extends back through the choana onto the palate. Bowman's glands are present in the main olfactory cavity at all stages, but are most abundant and best developed in terrestrial adults. They are lacking in the lateral olfactory epithelium of the main olfactory cavity. At the ultrastructural level, in aquatic animals receptor cells of the main olfactory cavity can have cilia, short microvilli, a mix of the two, or long microvilli. Supporting cells are of two types: secretory supporting cells with small, electron-dense secretory granules, and ciliated supporting cells. Receptor cells of the vomeronasal organ are exclusively microvillar, but supporting cells are secretory or ciliated, as in the main olfactory cavity. After metamorphosis two distinct types of sensory epithelium occur in the main olfactory cavity. The predominant epithelium, covering most of the roof and the medial part of the floor, is characterized by supporting cells with large, electron-lucent vesicles. The epithelium on the lateral floor of the main olfactory cavity, by contrast, resembles that of aquatic animals. Both types have both microvillar and ciliated receptor cells. No important changes are noted in cell types of the vomeronasal organ after metamorphosis. A literature survey suggests that some features of the metamorphic changes described here are characteristic of all salamanders, while others appear unique to D. tenebrosus.     

Feeding Motor Patterns in Anurans: Insights from Biomechanical Modeling

During feeding in anurans, the mouth opens while the tongue,which is attached to the mandible at the front of the mouth,rotates forward. Due to the relative simplicity of its anatomyand the complexity of its motion, tongue protraction in frogspresents an ideal system for exploring the neural control ofmultijoint movements. In this study, we used a forward dynamic,rigid body model with four segments and two muscles to investigateopen loop control of tongue protraction in the Australian white-lippedtree frog, Litoria caerulea. Model parameters include the massdistribution, initial position and initial angular velocityof each segment and the anatomy and physiology of each muscle.Model variables include the level of muscle activation at eachtime step and impulsive torques to open and close the mouth.The model gives X,Y coordinates of each segment and joint anglesat each time step as output. The model was tested using scaled,normalized EMG signals and impulsive joint torques to predictthe paths of the lower jaw tip and tongue tip. Predicted pathswere compared to experimentally observed paths using Pearsonproduct-moment correlation coefficients. Simulations demonstratethat the genioglossus muscles likely play a minor role, if any,in determining the trajectory of the tongue in most anurans.Most of the force for tongue protraction comes from angularmomentum transferred to the tongue by the opening jaws. In anurans,tongue protraction is dynamically stable and will occur as longas the musculoskeletal elements are in the correct initial position.     

Development of mating behaviour in the prepuberal ram

Several components of mating behaviour were observed in ram lambs between birth and weaning at 8 weeks. Mounting was most common, followed by nosing, flehmen and pawing. Ewe lambs exhibited the same behaviours, but fewer nosings and pawings. True sexual activity began between 9 and 20 weeks, with first ejaculation at about 27–30 kg and 140–180 days of age. Initially, behaviours were expressed in the order nose, nudge, paw, flehmen, lick, mount and ejaculate. With increasing age, flehmen occurred earlier in the sequence and pawing later. Competitive order was related to mounting activity, age at first ejaculation and total ejaculations. Ram lambs rely heavily on the sense of smell during their early sexual encounters. With increasing age and experience the vomeronasal system assumes considerable importance. Changes in the behavioural sequence need to be considered when testing libido during the puberal period.     

Prenatal repair of experimentally induced clefts in the secondary palate of the rat

A refined technique of amniotic sac puncturing at day 16.2 (i.e., 16 + 2/10 days) of gestation was employed in order to produce a series of total clefts and rare forms of partial clefts in Sprague-Dawley rat fetuses. From a total of 410 fetuses of a precise, individually determined age, 95 upper jaws were examined in the scanning electron microscope and, in part, in serial Epon sections. All fetal heads were examined macroscopically. Total clefts were found in 48.9% of a total of 184 viable rat fetuses examined at day 17.8 of smear age and in 21.8% of a total of 211 fetuses examined at day 19.3. Partial clefts were observed in 14.1% and 18.5% of fetuses at days 17.8 and 19.3 of smear age, respectively. At day 19.3, 16.1% of the viable fetuses showed a very inconspicuous, small abnormality (with residual clefting and incomplete fusion with the nasal septum) in the region of the palatine foraminae. Morphological observations suggested that under conditions of detained palatal closure (1) fusion of the soft palatal shelves commences independently from and prior to fusion of the hard palate, (2) delayed palatal shelf fusion proceeding in the anterior direction may occur with or without remaining sickle-shaped clefts in the anterior hard palate, and (3) in fetuses with small sickle-shaped clefts, fusion of the palatal shelves with the nasal septum does not occur. The present data imply that an almost total prenatal repair and delayed closure of the secondary palate may occur in rats that, at day 16.2 of multiple analysis age, most certainly had a total palatal cleft resulting from tongue resistance.