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Biometric study of the head region of the Darehshori horse
2015
Shojaei, Bahador | Sajjadian, Seyed Mohsen | Soleiman Poor Moghadam, Morteza
BACKGROUND: Considering differences in head size and shape of different Equine breeds, biometric parameters can be an attribute to a particular race. OBJECTIVES: The purpose of the present paper is to give a numerical definition of morphological characteristics of head region of the Darehshori horse. METHODS: Twenty mature Darehshori horses were studied biometrically. The ear length, ears distance, eyes distance, head length, lateral head length, head width, rostrum length, distance between two mandibles and lateral face length were measured and the averages were calculated. RESULTS: The average of the related characters were as follow; ear length 16.89, ears distance 12.12, eyes distance 15.79, head length 55.26, lateral head length 49.33, head width 20.42, rostrum length 23.68, distance between two mandibles 10.82 and lateral face length 39.88 centimeter. CONLUSIONS: The coefficient of variation of these characters showed that the head length, lateral face length and lateral head length are more reliable characters than the other indices in characterizing the Darehshori horse.
Afficher plus [+] Moins [-]Comparison of antinociceptive, cardiovascular, and respiratory effects, head ptosis, and position of pelvic limbs in mares after caudal epidural administration of xylazine and detomidine hydrochloride solution.
1996
Skarda R.T. | Muir W.W. III.
Evoked potentials induced by transcranial stimulation in dogs.
1990
Kraus K.H. | O'Brien D. | Pope E.R. | Kraus B.H.
Evoked potentials were induced by transcranial stimulation and recovered from the spinal cord, and the radial and sciatic nerves in six dogs. Stimulation was accomplished with an anode placed on the skin over the area of the motor cortex. Evoked potentials were recovered from the thoracic and lumbar spinal cord by electrodes placed transcutaneously in the ligamentum flavum. Evoked potentials were recovered from the radial and sciatic nerves by surgical exposure and electrodes placed in the perineurium. Signals from 100 repetitive stimuli were averaged and analyzed. Waveforms were analyzed for amplitude and latency. Conduction velocities were estimated from wave latencies and distance traveled. The technique allowed recovery of evoked potentials that had similar characteristics among all dogs. Conduction velocities of potentials recovered from the radial and sciatic nerves suggested stimulation of motor pathways; however, the exact origin and pathway of these waves is unknown.
Afficher plus [+] Moins [-]Conduction velocities and myelinated fiber diameter spectra of the infraorbital and palpebral nerves of the dog.
1986
Whalen L.R. | Carsten R.E.
Study on body measurement of fetuses and neonates in Korean native goats.
1988
Kim C.S. | Choe S.Y. | Chung H.S. | Kim T.S.
The measurement was investigated with 18 heads of fetus (60, 90, 120 days of gestation) and neonate in Korean native goats. The crown-rump length of fetuses at 60, 90, 120 days of gestation and neonate was 8.71, 20.83, 31.10 and 34.93 cm, respectively. The length of small intestine at 60, 90, 120 days of gestation and neonate was 32.28, 157.10, 303.52 and 475.06 cm, respectively. The length of large intestine at 60, 90, 120 days of gestation and neonate was 9.20, 37.70, 82.06 and 94.46 cm, respectively. The head length at 60, 90, 120 days of gestation and neonate was 2.93+-0.07, 6.67+-0.13, 8.84+-0.51 and 9.76+-0.44 cm, respectively. The width of the head at 60, 90, 120 days of gestation and neonate was 2.20+-0.13, 4.45+-0.11, 5.33+-0.20 and 5.51+-0.32 cm, respectively.
Afficher plus [+] Moins [-]Dependence of sperm morphology and ejaculate characteristics on sperm concentration in the ejaculates of Hypor boars
2018
Górski, Krzysztof | Kondracki, Stanisław | Wysokińska, Anna | Iwanina, Maria
Determination of sperm concentration and morphology in ejaculate is essential in evaluating fertility. Sperm shape and dimensions may depend on their concentration in ejaculate. The aim of the study was to evaluate the dependence of Hypor boar morphological and morphometric sperm characteristics on concentration in ejaculate. The study was conducted on 120 ejaculates from 12 Hypor boars. Depending on sperm concentration, they were put into three groups: low, medium, and high. Ejaculate sperm concentration was determined with the photometric method. Slides were prepared from semen samples which were evaluated for the morphology of spermatozoa. The preparations for morphological analyses were by the eosin-gentian staining method. As the sperm concentration in the ejaculate increased, the length, perimeter, and area of the sperm heads also did. In the ejaculates with higher sperm concentration the sperm heads were rounder. The ratios of head dimensions to tail length or total length were the highest in the sperm from ejaculates with the highest concentrations. The highest percentage of morphologically abnormal sperm was noted in ejaculates with low concentrations. The dimensions and shape of sperm depend on the sperm concentration in the ejaculate. In ejaculates with the highest concentrations, the sperm have larger dimensions. Sperm concentration affects the frequency of morphological anomalies in the spermatozoa.
Afficher plus [+] Moins [-]Computed tomographic assessment of brain tissue disruption and skull damage in equine cadaveric heads caused by various firearm-ammunition combinations applied as potential gunshot methods for euthanasia of horses
2021
Lund, Jane R. | Ketover, Howard R. | Hetzel, Scott | Waller, Kenneth | Brounts, Sabrina H.
OBJECTIVE To evaluate with CT the characteristics of brain tissue disruption and skull damage in cadaveric heads of adult horses caused by each of 6 firearm-ammunition combinations applied at a novel anatomic aiming point. SAMPLE 53 equine cadaveric heads. PROCEDURES Heads placed to simulate that of a standing horse were shot with 1 of 6 firearm-ammunition combinations applied at an aiming point along the external sagittal crest of the head where the 2 temporalis muscles form an inverted V. Firearm-ammunition combinations investigated included a .22-caliber long rifle pistol firing a 40-grain, plated lead, solid-core or hollow-point bullet (HPB); a semiautomatic 9-mm pistol firing a 115-grain, jacketed HPB; a semiautomatic .223-caliber carbine firing a 55-grain, jacketed HPB; a semiautomatic .45-caliber automatic Colt pistol firing a 230-grain, jacketed HPB; and a 12-gauge shotgun firing a 1-oz rifled slug. Additional heads placed in a simulated laterally recumbent position were shot with the semiautomatic 9-mm pistol–HPB combination. All heads underwent CT before and after being shot, and images were evaluated for projectile fragmentation, skull fracture, and cerebrum, cerebellum, and brainstem disruption. RESULTS Computed tomography revealed that all firearm-ammunition combinations caused disruption of the cerebrum, cerebellum, and brainstem that appeared sufficient to result in instantaneous death of a live horse. Hollow-point ammunition was as effective as solid-core ammunition with regard to brain tissue disruption. Brain tissue disruption was not affected by head positioning. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that the examined firearm-ammunition combinations, when applied at a novel aiming point, appear to be reasonable options for euthanasia of horses.
Afficher plus [+] Moins [-]Effects of kernel and window setting combinations on assessments of small and complicated vasculature in computed tomography angiographic images of dogs with and without tumors
2020
Yoon, Sooa A. | Park, Seungjo J. | Choi, Jihye H.
OBJECTIVE To evaluate the effect of kernel and window settings on the assessment of small and complicated vasculature in CT angiographic (CTA) images of kidneys, jejunum with mesentery, and tumors in dogs. ANIMALS 20 healthy dogs and 20 dogs with tumors. PROCEDURES Images from CTA performed previously in dogs were reconstructed with 3 different combinations of kernel and window settings (soft kernel with soft tissue window, soft kernel with bone window, and sharp kernel with bone window), and reconstructed images of the left kidney and the jejunum with the mesentery in healthy dogs and tumors in affected dogs were evaluated by reviewers blinded to the settings. RESULTS For images of kidney and jejunum with mesentery, reviewers’ scores for the conspicuity of vascularity in the arterial phase and the differentiation of the organs from the adjacent structures were significantly higher when viewed in bone window (vs soft tissue window) regardless of kernel setting. For images of head and gastrointestinal tumors, reviewers’ scores for differentiation of intratumoral vasculature were higher when viewed in sharp kernel with bone window versus other setting combinations. However, the conspicuity of gastrointestinal, hepatic, or splenic tumoral vessels from the adjacent structures had higher reviewer scores for images in soft kernel with soft tissue window, compared with other setting combinations. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that reconstruction of CTA images with sharp kernel combined with bone window settings might have clinical utility in evaluating and planning treatments for dogs with various tumors; however, additional research is warranted to further identify effects of various kernel and window setting combinations on assessments of small and complicated vasculature in larger and more diverse populations of dogs with and without tumors.
Afficher plus [+] Moins [-]Kinematic analysis of mandibular motion before and after mandibulectomy and mandibular reconstruction in dogs
2019
Arzi, Boaz | Verstraete, Frank J. M. | Garcia, Tanya C. | Lee, Monica | Kim, Se Eun | Stover, Susan M.
OBJECTIVE To evaluate and quantify the kinematic behavior of canine mandibles before and after bilateral rostral or unilateral segmental mandibulectomy as well as after mandibular reconstruction with a locking reconstruction plate in ex vivo conditions. SAMPLE Head specimens from cadavers of 16 dogs (range in body weight, 30 to 35 kg). PROCEDURE Specimens were assigned to undergo unilateral segmental (n = 8) or bilateral rostral (8) mandibulectomy and then mandibular reconstruction by internal fixation with locking plates. Kinematic markers were attached to each specimen in a custom-built load frame. Markers were tracked in 3-D space during standardized loading conditions, and mandibular motions were quantified. Differences in mandibular range of motion among 3 experimental conditions (before mandibulectomy [ie, with mandibles intact], after mandibulectomy, and after reconstruction) were assessed by means of repeated-measures ANOVA. RESULTS Both unilateral segmental and bilateral rostral mandibulectomy resulted in significantly greater mandibular motion and instability, compared with results for intact mandibles. No significant differences in motion were detected between mandibles reconstructed after unilateral segmental mandibulectomy and intact mandibles. Similarly, the motion of mandibles reconstructed after rostral mandibulectomy was no different from that of intact mandibles, except in the lateral direction. CONCLUSIONS AND CLINICAL RELEVANCE Mandibular kinematics in head specimens from canine cadavers were significantly altered after unilateral segmental and bilateral rostral mandibulectomy. These alterations were corrected after mandibular reconstruction with locking reconstruction plates. Findings reinforced the clinical observations of the beneficial effect of reconstruction on mandibular function and the need for reconstructive surgery after mandibulectomy in dogs.
Afficher plus [+] Moins [-]Perfusion computed tomographic measurements of cerebral blood flow variables in live Holstein calves
2018
Kishimoto, Miori | Kushida, Kazuya | Yamada, Kazutaka
OBJECTIVE To measure cerebral blood flow (CBF) and cerebral blood volume (CBV) by means of perfusion CT in clinically normal Holstein calves. ANIMALS 9 Holstein calves. PROCEDURES Each of the 9 calves (mean age, 20.2 days) was anesthetized and received an injection of iodinated contrast medium into the right jugular vein at a rate of 4.0 mL/s. Dynamic CT scanning of the head at a level that included the mandibular condyle was initiated at the time of the contrast medium injection and continued for 100 seconds. A deconvolution method was used as an analytic algorithm. RESULTS Among the 9 calves, the mean ± SD CBF in the cerebral cortex, white matter, and thalamus was 44.3 ± 10.3 mL/100 g/min, 36.1 ± 7.5 mL/100 g/min, and 40.3 ± 7.5 mL/100 g/min, respectively. The CBF in white matter was significantly lower than that in the cerebral cortex or thalamus. The mean CBV in the cerebral cortex, white matter, and thalamus was 6.8 ± 1.0 mL/100 g, 5.2 ± 1.0 mL/100 g, and 5.7 ± 0.7 mL/100 g, respectively. The CBV in the cerebral cortex was significantly higher than that in the white matter or thalamus. CONCLUSIONS AND CLINICAL RELEVANCE Measurement of CBF and CBV in clinically normal calves by means of perfusion CT was feasible. The data obtained may be useful as baseline values for use in future research or for comparison with findings from calves with CNS diseases. Investigations to determine the lower limit of blood flow at which brain function can still be restored are warranted.
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