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In this study, we developed a calving prediction model based on continuous measurements of ventral tail base skin temperature (ST) with supervised machine learning and evaluated the predictive ability of the model in 2 dairy farms with distinct cattle management practices. The ST data were collected at 2- or 10-min intervals from 105 and 33 pregnant cattle (mean ± standard deviation: 2.2 ± 1.8 parities) reared in farms A (freestall barn, in a temperate climate) and B (tiestall barn, in a subarctic climate), respectively. After extracting maximum hourly ST, the change in values was expressed as residual ST (rST = actual hourly ST - mean ST for the same hour on the previous 3 d) and analyzed. In both farms, rST decreased in a biphasic manner before calving. Briefly, an ambient temperature-independent gradual decrease occurred from around 36 to 16 h before calving, and an ambient temperature-dependent sharp decrease occurred from around 6 h before until calving. To make a universal calving prediction model, training data were prepared from pregnant cattle under different ambient temperatures (10 data sets were randomly selected from each of the 3 ambient temperature groups

Background: Ventral abdominal herniation (with or without oviduct involvement) in avian species is most commonly seen in reproductively active females. Case Description: A 2.5-year-old female budgerigar (Melopsittacus undulatus) presented for a ventral tail, 2.0 cm in diameter, mass extending between the cloaca and the tail base. Upon surgical evaluation, the mass was determined to be a herniation of the oviduct and later confirmed with histopathology. A salpingohysterectomy and closure of the body wall defect was performed, and the patient recovered well. Postoperative radiography revealed no evidence of retained egg or other obvious pathology to determine an underlying cause. Conclusions and Case Relevance: Lateral body wall herniations with involvement of the oviduct has been reported, but an undertail body wall herniation involving the oviduct has not been previously reported based on the literature search, and should be considered in birds presented with similar lesions in this anatomical location.

Prediction of parturition is essential for sustainable production in beef and dairy cattle, yet the present methods are limited by their high invasiveness and low utility. Here we compared prepartum changes in ventral tail base surface temperature (ST) with changes in vaginal temperature (VT) and behavioral indices. We analyzed 22 parturitions from 22 beef cows. Changes in daily values of ST, VT, and behavioral indices over the 7 days before parturition were investigated. Hourly values were calculated as the actual values minus the mean values for the same hour over a 3-day period, and the changes in hourly values over the 48 h before parturition were investigated. To test the effect of ambient temperature, tested cows were assigned to two season-groups based on the ambient temperature to which they were exposed (warm: n = 13; cool: n = 9), and the daily and hourly values of the indices were compared between seasons. A decrease in ST occurred approximately 30 h before parturition, which was similar to the time of the decrease in VT and earlier than the increase of behavioral indices. In addition, a unique fluctuation of ST observed in the last few hours before parturition indicates that ST could provide a sign for parturition not only in the long-term like VT, but also in the short-term like behavioral indices. Although ST was more sensitive to ambient temperature than VT or the behavioral indices, the day of parturition could be predicted from ST in both the warm and cool seasons.

We tested whether striped skunks (Mephitis mephitis) in Flagstaff, Arizona, USA, could be recognized based on variation in pelage patterns and whether camera position influenced that outcome. We presented 11 volunteers with 2 sets of 24 photographs taken between 1 January and 15 February 2015, one with animals photographed from the side, the other from above. Each set of 24 photographs included 9 pairs, with each pair representing 2 different images of the same animal. Volunteers scored twice as many correct matches and 4-fold fewer false matches when photographs were taken from above. Regardless of camera position, the total number of unique skunks in each set was underestimated (83% of total from above, 75% from side), likely because some skunks had very similar pelage patterns. Our results indicate that variation in nose stripe, back stripe, dorsal and ventral tail pattern, and shape of tail can be used to recognize individual striped skunks but similarity in those characteristics among some individuals may cause total number of unique individuals to be underestimated regardless of camera orientation. © 2017 The Wildlife Society.

Dystocia adversely affects the health of calves and their dams. The aim of this study was to determine whether the ventral tail base surface temperature (ST) could be used to predict calving time in dairy cows. Pregnant Holstein cows were enrolled during the warm season (daily average air temperature 10-20°C; n=13) and cool season (daily average air temperature

In the present study, the ventral tail base surface temperature (ST) was monitored using a wearable wireless sensor for estrus detection in cattle. Relationships among ST, behavioral estrus expression, ovulation, and changes in hormone profiles during the estrous cycle were examined. Holstein Friesian or Japanese Black female cattle were used in summer (August-September), autumn (October-November) and winter (January-February; three animals per season). On Day 11 of the estrous cycle (Day 0=the day of ovulation), the sensor was attached to the surface of the ventral tail base and ST was measured every 2min until Day 11 of the next estrous cycle. Hourly maximum ST values were used for analysis. To exclude circadian rhythm and seasonal effects, ST changes were expressed as residual temperatures (RT=actual ST - mean ST for the same hour on the previous 3days). Obvious circadian rhythms of the ST were observed and daily changes in the ST significantly differed among seasons. There was no significant seasonal difference, however, in the RT. The mean RT increased significantly ∼24 compared with ∼48h before ovulation. The mean maximum RT was 1.27±0.30°C, which was observed 5.6±2.4h after the onset of estrus, 2.4±1.3h before LH peak, and 26.9±1.2h before ovulation. The ST of the ventral tail base could be monitored throughout the estrous cycle and could detect a substantial change around the time of expression of behavioral estrus. Calculation and analysis of the RT could be useful for automatic estrous detection.

Humpback whales Megaptera novaeangliae found off west South Africa (WSA) are known to display an atypical migration that may include temporary residency and feeding during spring and summer. At a regional scale there is uncertainty about how these whales relate to the greater West African Breeding Stock B as a whole, with evidence both for and against its division into two substocks. A database containing sighting information of humpback whales intercepted by boat in the WSA region from 1983 to 2008 was compiled. It included a total of 1 820 identification images of ventral tail flukes and lateral views of dorsal fins. After systematic within- and between-year matching of images of usable quality, it yielded 154 different individuals identified by tail flukes (TF), 230 by left dorsal fins (LDF), and 237 by right dorsal fins (RDF). Microsatellite (MS) matching of 216 skin biopsies yielded 156 individuals. By linking all possible sightings of the same individuals using all available identification features, the periodicity and seasonality of 281 individual whales were examined. In all, 60 whales were resighted on different days of which 44 were between different calendar years. The most resightings for one individual was 11 times, seen in six different years, and the longest interval between first and last sightings was about 18 years. A resighting rate of 15.6% of whales at intervals of a year or more indicates long-term fidelity to the region. Shorter intervals of 1–6 months between sequential sightings in the same year may suggest temporary residency. The TF image collection from WSA was compared to TF collections from four other regions, namely Gabon, Cabinda (Angola), Namibia and the Antarctic Humpback Whale Catalogue (AHWC). Three matches were detected between WSA (in late spring or summer) and Gabon (in winter), confirming direct movement between these regions. The capture–recapture data of four different identification features (TF, RDF, LDF and MS) from six successive subsets of data from periods with the highest collection effort (2001–2007) were used to calculate the number of whales that utilise the region, using both closed- and open-population models. Dorsal fins have never been used to estimate abundance for humpback whales, so the different identification features were evaluated for potential biases. This revealed 9–14% incidence of missed matches (false negatives) when using dorsal fins that would result in an overestimate, whereas variation in individual fluke-up behaviour may lower estimates by as much as 57–66% due to heterogeneity of individual capture probability. Taking into consideration the small dataset and low number of recaptures, the most consistent and precise results were obtained from a fully time-dependent version of the Jolly-Seber open-population model, with annual survival fixed at 0.96, using the MS dataset. This suggests that the WSA feeding assemblage during the months of spring and summer (September–March) of the study period numbered about 500 animals. The relationship of these whales to those (perhaps strictly migratory) that may occur in other seasons of the year, and their links to possible migratory routes and other feeding or breeding areas, remain uncertain.Keywords: abundance, Breeding Stock B, capture heterogeneity, capture–recapture, Chapman’s modified Petersen estimate, Megaptera novaeangliae, migration, photo-identification, Program MARK, site fidelityAfrican Journal of Marine Science 2011, 33(3): 353–373

Summary Growth, and potential marking-related mortality of small European eel Anguilla anguilla (L.) after marking with visible implant elastomer tags (VIE) and coded wire tags (CWT) were investigated over a 6-month period in a laboratory experiment. In addition, mark retention after marking was examined for another 16.5 months. Neither marking method had a significant effect on growth (P > 0.05) or mortality (P > 0.05). After 32 days detection of the VIE marks implanted on the ventral surface and along the base of the ventral tail fin margin was 98 and 100%, respectively, but decreased to 9 and 66% after 512 days. Retention of the CWT implanted in the dorsal musculature of A. anguilla was 99% after 32 days and did not change by day 512. It was therefore concluded that marking-induced mortality was nil for both marking types over the 6-month period. Generally, both methods are found to be suitable for marking young A. Anguilla. VIE tags, however, should be used for short-time mark-recapture experiments only, and should be injected at the base of the ventral fin margin. The use of CWTs seems to be the more suitable marking method for long-term mark-recapture experiments. Nevertheless, field tests are necessary to evaluate these marking methods.

A captive-born female sub-adult Eastern black rhinoceros (Diceros bicornis michaeli) developed areas of non-ulcerated, non-pruritic depigmentation around the nares at 2 yr of age. Over the subsequent 18 mo, the symmetrical multifocal depigmented macules increased in size and distribution to include facial fold crypts, interdigital skin, lips, nares, palmar carpi, ventral abdomen, ventral mandible, axillae, lateral brachium and antebrachium, lateral thighs, ventral tail, and perineal region with an estimated 15% of the skin affected. Facial fold skin biopsies revealed multifocal hypopigmentation with melanin incontinence and mild perivascular lymphohistiocytic dermatitis. The gross appearance and histologic lesions were consistent with vitiligo. Treatment with UV-B narrowband phototherapy was performed on the lateral thighs, lateral elbows, palmar carpi, and rostral maxilla for a period of 12 mo. Significant repigmentation of the treatment areas was achieved.

[Some prey attempt to deter pursuit by signaling to a predator that they have detected it and can escape if attacked. Zebra-tailed lizards ( Callisaurus draconoides ) wag their boldy patterned tails when approached. Wagging is related to predation risk, as predicted for pursuit deterrence, and likely alternative functions have been eliminated. To examine the role of tail-waving in pursuit-deterrence, I studied stages of predator–prey encounters when it occurred, its duration and its directedness. Tail-waving occurred before, during and after escape runs, and in all combinations of these times. Display performed before fleeing putatively deters pursuit; during and after fleeing it also might deflect attacks to the autotomizable tail. Tail-waving was brief before and during escape, but lasted up to 13 s after runs ended. Undetected ambushers at new locations attack rapidly and displaying may attract additional predators. Therefore, prolonged display for deflection is unlikely. Lizards display briefly, flee to reduce risk and possibly demonstrate escape ability, then engage in more prolonged signaling. As predicted for a directed signal, tail-waving frequency was higher for lizards oriented at angles that exposed the ventral tail to view than at hid it from view. Tail-waving appears to be a pursuit-deterrent signal directed to predators., Some prey attempt to deter pursuit by signaling to a predator that they have detected it and can escape if attacked. Zebra-tailed lizards ( Callisaurus draconoides ) wag their boldy patterned tails when approached. Wagging is related to predation risk, as predicted for pursuit deterrence, and likely alternative functions have been eliminated. To examine the role of tail-waving in pursuit-deterrence, I studied stages of predator–prey encounters when it occurred, its duration and its directedness. Tail-waving occurred before, during and after escape runs, and in all combinations of these times. Display performed before fleeing putatively deters pursuit; during and after fleeing it also might deflect attacks to the autotomizable tail. Tail-waving was brief before and during escape, but lasted up to 13 s after runs ended. Undetected ambushers at new locations attack rapidly and displaying may attract additional predators. Therefore, prolonged display for deflection is unlikely. Lizards display briefly, flee to reduce risk and possibly demonstrate escape ability, then engage in more prolonged signaling. As predicted for a directed signal, tail-waving frequency was higher for lizards oriented at angles that exposed the ventral tail to view than at hid it from view. Tail-waving appears to be a pursuit-deterrent signal directed to predators.]

Amphibian skin secretion is a rich source of biological compounds. Histological, morphometrical, functional, and protein biochemical methods were used to understand the role of skin glands in the tail of the red-legged salamander (Plethodon shermani), an emerging organismal model for the physiology and evolution of pheromonal communication. Individual granular glands were approximately three times larger in the dorsal tail skin compared to the ventral tail skin. Dorsal tail granular glands emptied when animals were handled to induce release of noxious/sticky substances. Ventral tail granular glands emptied during scent marking. Granular glands in both dorsal and ventral tail skin rapidly enlarged when animals were placed on a clean substrate. Histological study of tail skin identified a subset of ventral granular glands that stained differently from dorsal granular glands. Protein analysis of acetylcholine chloride extracts of dorsal tail skin and ventral tail skin revealed differences in the protein cont...

Anti-vibration gloves have been used to block the transmission of vibration from powered hand tools to the user, and to protect users from the negative health consequences associated with exposure to vibration. However, there are conflicting reports as to the efficacy of gloves in protecting workers. The goal of this study was to use a characterized animal model of vibration-induced peripheral vascular and nerve injury to determine whether antivibration materials reduced or inhibited the effects of vibration on these physiological symptoms. Rats were exposed to 4 h of tail vibration at 125 Hz with an acceleration 49 m/s(2). The platform was either bare or covered with antivibrating glove material. Rats were tested for tactile sensitivity to applied pressure before and after vibration exposure. One day following the exposure, ventral tail arteries were assessed for sensitivity to vasodilating and vasoconstricting factors and nerves were examined histologically for early indicators of edema and inflammation. Ventral tail artery responses to an α2C-adrenoreceptor agonist were enhanced in arteries from vibration-exposed rats compared to controls, regardless of whether antivibration materials were used or not. Rats exposed to vibration were also less sensitive to pressure after exposure. These findings are consistent with experimental findings in humans suggesting that antivibration gloves may not provide protection against the adverse health consequences of vibration exposure in all conditions. Additional studies need to be done examining newer antivibration materials.

In the present study, we investigated the vasodilatory effect of a novel scaffold Rho-kinase inhibitor, DL0805-2, on isolated rat arterial rings including mesenteric, ventral tail, and renal arteries. We also examined the potential mechanisms of its vasodilatory action using mesenteric artery rings.A DMT multiwire myograph system was used to test the tension of isolated small arteries. Several drugs were employed to verify the underlying mechanisms.DL0805-2 (10(-7)-10(-4) M) inhibited KCl (60 mM)-induced vasoconstriction in three types of small artery rings (pEC50: 5.84 ± 0.03, 5.39 ± 0.03, and 5.67 ± 0.02 for mesenteric, renal, and ventral tail artery rings, respectively). Pre-incubation with DL0805-2 (1, 3, or 10 μM) attenuated KCl (10-60 mM) and angiotensin II (AngII; 10(-6) M)-induced vasoconstriction in mesenteric artery rings. The relaxant effect on the rat mesenteric artery was partially endothelium-dependent (pEC50: 6.02 ± 0.05 for endothelium-intact and 5.72 ± 0.06 for endothelium-denuded). The influx and release of Ca(2+) were inhibited by DL0805-2. In addition, the increased phosphorylation levels of myosin light chain (MLC) and myosin-binding subunit of myosin phosphatase (MYPT1) induced by AngII were blocked by DL0805-2. However, DL0805-2 had little effect on K(+) channels.The present results demonstrate that DL0805-2 has a vasorelaxant effect on isolated rat small arteries and may exert its action through the endothelium, Ca(2+) channels, and the Rho/ROCK pathway.

The characteristic rhythmical discharges of single postganglionic sympathetic neurones (PSNs) innervating the caudal ventral tail artery (CVA) of anaesthetised rats can still be recorded following the sectioning of afferents arising from the tail and hindquarters. Consequently, we suggest that such rhythmical discharges are neither a 'local sign' sympathetic response nor a sympathetic correlate of 'escape behaviour'.

Unlike most teleosts, the seahorse (genus Hippocampus) is able to bend its tail ventrally, uses its tail in a postural role as a grasping and holding appendage, and possesses heavy body plates instead of scales. To investigate seahorse axial bending mechanisms and the role of plating in those mechanisms, observations were made on seahorses curling their tails ventrally and holding a support and components of the mechanical system used for axial bending, including dermal plates, vertebrae, and axial muscles, were examined. Anatomical modifications involved in ventral tail bending include hypertrophy of the ventral region of the hypaxial muscle, ventrolateral attachment of the myomeres to plates, and modification of the infracarinalis posterior muscles so that they act in axial bending rather than in fin movement as has previously been hypothesized (Harder, '75) for other fishes. Modifications for prehension include the presence of fibers histochemically characterized as tonic in the median ventral muscles (the modified infracarinalis muscle) and in portions of the myomeres. Dermal plates are an important part of the force transmission system used in seahorse tail bending. They transmit forces from the hypaxial myomeres to bend the tail both laterally and ventrally. This study expands our understanding of axial bending in fishes by examining extreme modifications of the musculoskeletal system associated with the evolution of unique functional capabilities within teleosts. © 1996 Wiley-Liss, Inc.

The histological and ultrastructural status of intact and severed axons was examined in the ventral tail nerve of rats whose tails were maintained at 32, 23, and 13 degrees C. Compared to contralateral intact nerves, distal (anucleate) portions of severed myelinated axons morphologically and ultrastructurally degenerated within 3 days at 32 degrees C and within 6 days at 23 degrees C. In contrast, anucleate myelinated axons in ventral tail nerves maintained at 13 degrees C did not degenerate for at least 10 days. These and other data suggest that rapid Wallerian degeneration of anucleate myelinated axons is not an inevitable result of axonal severance in mammals.

Observations recorded in eastern Saudi Arabia on ventral tail colouration associated with maturity and social tail signalling in populations of the Arabian Toad-head Agamid Phrynocephalus arabicus.

The most common technique used for collecting blood samples from chameleons, ventral tail caudal venipuncture (Reptile care. An Atlas of Diseases and Treatments, Vol. II, T.F.H. Publication, New Jersey, 1991) sometimes presents undesired effects. Here we compared tail versus jugular vein venipuncture techniques in the common chameleon. In the first experiment, we collected 0.25% of the chameleon's body mass in blood from either tail or jugular sites in size-matched pairs of animals to check for secondary effects. In a second experiment, we measured white blood cells (WBC), red blood cells (RBC), total plasma protein and uric acid in blood samples collected from both sites in the same individual. We found few secondary effects following the use of either venipuncture site although skin darkening was observed in few specimens when using the ventral tail vein. Blood profiles were similar between samples. The repeatability of measurements was similar in RBC and WBC counts and remarkably low (0.90). Despite the few differences recorded, we recommend jugular venipunction in chameleons as skin darkening is unlikely, blood volumes are easily obtained and collection time is shorter.

The site and mode of action of serotonin on locomotion were investigated in the parasitic nematode Ascaris suum. Injection of serotonin into Ascaris immediately caused paralysis in animals that were generating locomotory waveforms. Injected serotonin also increased body length and decreased the number of propagating body waves. Similar injections into the male tail produced a ventral tail curl. Injection of N-acetyl-serotonin had no effect on the generation of locomotory waveforms, but increased the body length and decreased the number of body waves in the waveform. Other biogenic amines were also tested but were much less potent. Serotonin decreased the amplitude of a submaximal acetylcholine-induced muscle contraction and increased the time to attain this contraction. The time course of this effect on the response to ACh was much slower than the action of injected serotonin on locomotory waveforms, suggesting that additional elements are involved in the action of serotonin on locomotory behavior. Serotonin abolished spontaneous slow potentials in VI motor neurons and decreased the frequency of EPSPs in DE2 motor neurons, probably by a pre-synaptic mechanism. In the male tail, serotonin depolarized the male-specific transverse ventral muscle cells, but did not affect either dorsal or ventral longitudinal muscle cells.

Hemodynamics and 3D- architecture of the vascular network of the ventral tail fin of tadpoles of the South African Clawed Toad, Xenopus laevis Daudin were studied by intravital video microscopy (IVM) (stage 56) and vascular corrosion casts (VCCs)(stage 58). IVM enabled a detailed study of the circulation in segmental arteries, segmental venules and interposed capillaries. SEM of VCCs and 3-D morphometry allowed exact measurements of vessel diameters.Anuran tadpoles are good models to study blood vessel growth (=angiogenesis) (1-3) as well as blood vessel regression which occurs physiologically when tadpoles loose larval specific organs such as gills and tail during metamorphosis (4,5). The translucent ventral tail fin enables in-vivo observations of the living circulation by intravital light microscopy (1,2) and allows correlations between vessel fine structure and dynamics of blood flow under various conditions (2).This study focuses on the 3D-architecture of the blood vascular system in the ventral tail fin of tadpoles of Xenopus laevis Daudin in stage 58, i.e. at the begin of metamorphic climax.

In a single blind study the gender of nine adult Mexican beaded lizards, Heloderma horridum and 35 adult Gila monsters, Heloderma suspectum of known sex was determined by two dimensional ultrasound imaging of the ventral tail just distal to the cloaca. In each case subjects could be sorted into two distinct morphologic groups. Group 1 animals had large, variably hypoechoic, paired soft tissue structures in the ventral aspect of the tail spanning 2 cm distal to the vent, while the distal tail lacked these structures. Group 2 animals lacked this characteristic altogether, giving the ventral tail a much more consistent ultrasonic complexion along the entire length. The most logical conclusion for this difference was the presence of paired hemipenes in group 1 animals. Using this premise, subjects in group 1 were declared males, while group 2 animals were declared females. The predictions matched the known sexes of each individual in every case for adult lizards. One juvenile Gila monster could not b...

A new dasyatidid stingray,Dasyatis izuensis sp. nov., from Japan is described on the basis of specimens collected from the Izu Peninsula. The new species is distinguished by having the following characters: diamond-shaped disc; dorsal tail keel; white ventral tail fold, its length 24.6–32.3% of disc width; short preorbital snout length, 14.1–18.7% of disc width; smooth body even in adults except for a row of 2–6 small tubercles before tail spine; and 18–20 intestinal valve turns.

The contribution of the preweanling maternal environment to the development of hypertension was examined using the technique of reciprocal cross-fostering between two inbred rat strains, the Dahl hypertension-sensitive (SS/Jr) rat and the Dahl hypertension-resistant (SR/Jr) rat. Litters of SS/Jr and SR/Jr pups were reared by their natural mother, in-fostered to a dam of the same strain, or cross-fostered to a dam of the opposite strain for the entire preweanling period from postnatal days 1 to 30. At 60 and 100 days of age, one rat from each litter was surgically prepared with an indwelling catheter in the ventral tail artery. One day after surgery, measures of resting mean arterial pressure and heart rate were taken as the animals were resting and undisturbed in their home cages. Body weights were also obtained at 30, 60, and 100 days of age as a measure of general somatic development. Our findings indicate that SS/Jr rats fostered to SR/Jr dams exhibited a significant reduction in resting mean arterial pressure compared with naturally reared or in-fostered SS/Jr rats (P less than 0.01 at 60 days and P less than 0.03 at 100 days). Conversely, arterial pressure of SR/Jr rats did not differ across rearing conditions at either age. Body weights were not significantly affected by cross-fostering in either strain. We conclude from these results that characteristics of the SS/Jr maternal environment interact with the inbred genetic susceptibility of the SS/Jr pup to elicit the full expression of the SS/Jr hypertensive phenotype.

Electrical characteristics of in vitro preparations of the ventral tail nerve were compared in rats exposed for 6 months to outdoor winter cold and control rats kept indoors at 24 C. Determinations of conduction velocity, excitability, and action potential height demonstrated changes in nerve function following outdoor cold exposure. Differences between nerves of outdoor and indoor rats were greatest at higher nerve temperatures (35 C), becoming less at lower temperatures, until no differences were present at 5 C. Conduction velocity showed the greatest changes with cold exposure. Excitability changes could only be demonstrated with stimulus durations less than .1 msec. No differences in absolutely refractory period were seen between cold-exposed and control rats. In general, changes that occurred with cold exposure resulted only in a decrease in the functions examined. The results show that changes in peripheral nerve function can occur in nonhibernating mammals following prolonged exposure to climatic cold, but that these changes are not necessarily of an adaptive nature.

A modified cilium with an adhesive function has been found in an interstitial marine turbellarian Paratomella rubra (Acoela). This newly discovered cilium-type is referred to as a haptocilium; it differs structurally from usual locomotory cilia only in the morphology of the tip. Inside the haptocilial tip is a lamellate, electron-dense core, and visible outside the ciliary membrane of the tip is an amorphous secretion which is presumably the actual adhesive material by which the haptocilia are able to attach to surfaces. Haptocilia occupy a restricted area, a ventral tail plate, in Paratomella. They are motile and display a characteristic slow, irregular beat.

A comparison was made of the responses of helical strips of rat ventral tail artery from rats killed by cervical dislocation and rats subjected to poly-drug anesthesia. Anesthetized rats were premedicated with meperidine and atropine. Anesthesia was induced with thiopental and maintained with N2O. The animals were paralyzed with pancuronium and ventilated for 1 h. A mixture of fentanyl and droperidol was administered during anesthesia. Responses of arterial strips from these rats to norepinephrine, 5-hydroxytryptamine, vasopressin, and transmural electrical stimulation were identical with those of similar strips from control rats. Poly-drug anesthesia does not alter responses of isolated strips subsequently studied in vitro.

Summary The thermographic effects of applying an irritating substance to the anal sphincter (gingering) were assessed using 2 different agents in 10 and 8 horses respectively. The results were analyzed to determine if thermography would be a suitable means to detect if a horse had been “gingered.” The first agent was a 15 percent methyl salicylate, 10 percent menthol solution in a unibase suspension and the second agent was ginger in a unibase suspension. The temperature difference between the anal sphincter and the perineal region and tail were determined. In the non-gingered horse the temperature difference between the anal sphincter and perineum ranges between 0.5 C and 1.5 C with a mean of 0.78 C. The temperature difference between the anal sphincter and ventral tail ranged between 0.5 C and2.5 C with a mean of 1.33 C. The first agent caused the mean temperature differences between anal sphincter and perineum to decrease to 0.3 C within 15 minutes and the mean difference between anal sphincter and ventral tail to decrease to 0.45 C within 60 minutes. Application of the second agent caused the anal sphincter/perineum mean temperature difference to decline to 0.41 C within 5 minutes and the anal sphincter/ventral tail mean temperature to decline to 0.44 C within 5 minutes. These results, show that the application of these “gingering” agents does cause changes in the thermal patterns around the anus and that thermography can be used to detect a “gingered” horse. “Gingering” is the horseman's term for the application of a mildly irritating substance to the anus and perineal region of a horse for the specific intent of causing the horse to raise its tail. Certain breedassociations (Arabian, Saddlebred and Morgan Horses) consider a high tail carriage desirable. This traitis especially desirable in the show ring and a horse must exhibit this trait if it is going to compete successfully. “Gingering” is an artificial means of achieving this. Thermography displays surface temperatures of an object 3 . It is a noninvasive, non-contacting technique that measures infrared emissions. These emissions can be related directly to local circulation and metabolism 1 6 7 14 l5 . Thermography has been used for evaluation of various acute and chronic inflammatory conditions in horses 2 4 5 7 – 13 . The purpose of this project was to investigate the possible use of thermography as a means of detecting a gingered horse.

The tail bud was completely extirpated down to the yolk from 65 embryos at stages 13-17 to determine whether the posterior part of the noto-chord originates from the tail bud or from a more anterior region (i.e., prospective notochordal region). About 40% of the 44 surviving embryos developed near-normal tails, containing a localized defective region beginning near the base of the tail and extending a short distance posteriorly, about 15% developed truncated, cone-shaped tails, containing a defective region beginning near the base of the tail and extending towards the tip, and about 45% developed short, ventral tail remnants, containing a localized defective region beginning near the base of the tail and extending a short distance posteriorly. The tail was absent in only one embryo. These differences were probably due primarily to variation in the amount of healing and regeneration that occurred, and were independent of the stage at which the operation took place. The tail region has a tremendous capacity for regeneration since a near-normal tail frequently developed. The location of the beginning of the defective region near the base of the tail suggests that the tail bud primarily gives rise to tail structures. All embryos had neural tube defects, about 30% developed large, midline somites within the defective region, and about 25% developed an ourenteric outgrowth. The notochord was always normal within the defective region. These results are consistent with the view that the tail bud contributes cells to the posterior part of the neural tube, but not to the notochord.

Segments of the ventral tail artery from DCA-hypertensive and normotensive rats were artificially perfused at pressures from 60 to 120 mm Hg. Contraction of the segments was induced by the addition of norepinephrine to the perfusate or by increasing the K+ concentration of the perfusate. Contraction was abolished by removing Ca ++ from the perfusate and re-established by addingCa ++ to the Ca ++ -free perfusate. The experiments demonstrate hyperresponsiveness of the hypertensive artery in three ways: first, the hypertensive artery performed more work than the normotensive artery; second, contraction in the hypertensive artery was more difficult to abolish during zero Ca ++ perfusion; and third, less Ca ++ was required to re-establish the abolished contraction in the hypertensive artery. When the artificially perfused artery segments were analyzed for cations, the hypertensive arteries were found to contain increased amounts of Na + , K + , Mg ++ , and Ca ++ . After zero Ca ++ -Krebs perfusion, the hypertensive and normotensive arteries contained similar amounts of Ca ++ and Mg ++ , indicating that more Ca ++ was removed from the hypertensive artery. The results suggest that hyperresponsiveness may be due to an increased efficiency in either Ca ++ utilization during excitation coupling or in the contractile mechanism itself.

General Appearance.-Tadpole small, maximum total length before metamorphosis 30 to 32 mm.; tail tip obtuse, rounded; tail slightly attenuated toward tip; dorsal crest extended to about the vertical of the spiracle; spiracle sinistral, below lateral axis, directed backward and very slightly upward; spiracle opening round, the inner edge very slightly free from body; eye very slightly dorsal to lateral axis; anus dextral, opening about on the level of the ventral crest. Body uniformly and closely stippled with iridescent bronze; eyes closely stippled with bronze; body quite transparent; dorsal and ventral tail crests with finely scattered pigment areas, dark brown in color (preserved material); dorsal musculature of tail heavily pigmented, ventral musculature slightly less.