bluuebunny/crossref_metadata_2025_split huggingface dataset:
Histological aspects of uterine involution in the post parturient, ovariectomised, embryo‐recipient mare: a model for the study of involution
Authors: SERTICH PATRICIA L. , HINRICHS KATRIN , KENNEY R. M. 
Published: June 2010

SummaryThis paper compares uterine involution in intact and ovariectomised embryo recipient mares after foaling. There was no difference in the rate of uterine involution between the two groups and on Day 1 post partum intact and ovariectomised mares both have degenerating microcaruncles in the Stratum compactum. At this time the endometrial glands are tortuous and distended along their entire length. By Day 7 post partum the only remaining evidence of the microcaruncle is an area of condensed stroma containing siderophages and a few other mononuclear cells and covered by an intact epithelium. By Day 10 to 11 the cystic glandular distention has resolved.
An attempt to use progesterone treated XO mares as embryo recipients
Authors: PASHEN R. L. , DOWNIE C. , McCUE P. 
Published: June 2010

SummaryXO mares were evaluated as potential embryo transfer recipients. In the first part of the study, they were treated with oestrogen and progesterone for 10 and 14 consecutive days. During this course of steriod treatment, their endometria changed in histological appearance from anoestrous to dioestrous and their peripheral plasma progesterone levels rose from below 0.3 ng/ml to above 2 ng/ml. Plasma LH concentrations also rose during the period of oestrogen administration but declined again to baseline when progesterone treatment began. Urinary oestrogen concentrations rose and fell in conjunction with oestrogen treatment. In the second part of the study 16 Day 7 embryos were transferred non‐surgically to seven XO mares given daily injections of progesterone and 12 embryos were transferred to eight ovariectomised mares treated similarly with progesterone. Pregnancies were established in five of the ovariectomised mares but not in any of the XO mares. The possible reasons for the failure to establish pregnancy in the XO mares are discussed.
Results from an embryo transfer programme with Mangalarga mares in Brazil
Authors: FLEURY J. J. , NETO J. B. F. COSTA , ALVARENGA M. A. 
Published: June 2010

SummarySixty Mangalarga mares aged two to 28 years were used as donor mares in an embryo transfer programme. They were inseminated on alternate days during oestrus with fresh extended semen collected from a fertile Mangalarga stallion. Non‐surgical embryo recovery was performed on Day 7, 8 or 9 after ovulation (Day 0), using three consecutive uterine flushes of 500, 250 and 250 ml of Dulbecco's phosphate buffered saline. Embryos were transferred surgically to recipient mares between Days 4 and 9 post ovulation. The overall embryo recovery rate was 52.3 per cent (90/172). The recovery rate from seven mares under three years old was 85.0 per cent (17/20), whereas the rate from 34 mares aged three to 18 years was 64.4 per cent (58/90), and from 19 mares more than 18 years old was only 24.1 per cent (15/62). The overall pregnancy rate for the recipient mares at Day 50 was 78.9 per cent.
Transfer of cryopreserved equine embryos to progestin‐treated ovariectomised mares
Authors: SQUIRES E. L. , SEIDEL G. E. , MCKINNON A. O. 
Published: June 2010

SummaryGood to excellent quality embryos between 160 and 980 μm in diameter were recovered 6.5 to 7 days after ovulation and washed in Dulbecco's phosphate‐buffered saline plus 10 per cent foetal calf serum (PBS). Embryos were frozen in 0.5 ml French straws and seeded at −6°C. Embryos of 200 μm diameter or less were placed in 10 per cent glycerol in PBS and cooled from −6 to −30°C at 0.3°C/min, then to −33°C at 0.1°C/min. They were then plunged into liquid nitrogen. Embryos larger than 200 μm were frozen either 1) in 10 per cent glycerol plus 8.6 per cent sucrose with cooling at 0.5°C/min from −6 to 25°C followed by plunging, or 2) in 15 per cent glycerol plus 15 per cent sucrose and placed between gel‐containing cold packs in a household freezer at — 25°C for 30 mins followed by plunging. Embryos were thawed for 20 sees in a 37°C water bath or held in air for 20 sees prior to thawing in a 37°C water bath for 20 sees. Glycerol from embryos frozen in the household freezer was removed in steps of 12, 9, 6, 3 and 0 per cent glycerol, all with 10 per cent sucrose, 6 mins/step. Glycerol was removed similarly for other treatments but the first two steps were omitted. Embryos were evaluated morphologically (1 = excellent, 5 = severely degenerate) prior to transfer to the uterus of ovariectomised mares between 24th November and 9th January. Mares were given 0.044 mg/kg bodyweight altrenogest for at least six days. Four pregnancies were established after transferring eight embryos 200 μm or less, demonstrating that progestin‐treated, ovariectomised mares can serve as recipients for frozen embryos during the non‐breeding season. However, only two of 24 larger embryos resulted in pregnancy. No difference was detected in the two methods of cooling, but post‐thaw embryo quality was markedly improved (p<0.01) by holding straws in air for 20 sees prior to placing them in a water bath.
Bisection of equine embryos
Authors: McKINNON A. O. , CARNEVALE E. M. , SQUIRES E. L. , CARNEY N. J. , SEIDEL G. E. 
Published: June 2010

SummaryThree experiments were designed to evaluate methods of bisecting equine embryos. Viability of demi‐embryos was compared to whole embryosin vitroandin vivo.In Experiment 1, Day 6 embryos were bisected either using a standard micromanipulation technique or a manual split of embryos that were adhered to a petri dish. Viability was assessed by culturein vitro.Bisected embryos in both groups increased in size during culture and developed normally. In general, manual bisection was accomplished with less difficulty and time than the micromanipulation method. Eleven additional embryos were bisected manually and both halves transferred surgically into the same recipient (Experiment 2). More pregnancies were obtained from transfer of twin whole embryos (16/22) compared to bisected, demi‐embryos (5/22). In Experiment 3, 30 embryos were bisected manually; 15 were encapsulated in agar chip. Both halves were transferred non‐surgically to each recipient. Fifteen whole embryos were transferred non‐surgically to recipients as controls. The number of vesicles per original embryo was greater for whole embryos than for demi‐embryos in agar chips.
Iridial hypoplasia (aniridia) accompanied by limbic dermoids and cataracts in a group of related Quarterhorses
Authors: JOYCE J. R. , MARTIN J. E. , STORTS R. W. , SKOW L. 
Published: June 2010

SummaryThe clinical, gross and microscopic ophthalmic lesions of iridial hypoplasia, limbic dermoids and cataracts in a Quarterhorse stallion and a group of its offspring are described. It is proposed that the lesions in the stallion were the result of an independent mutation and that the defects were transmitted to its offspring by an autosomal dominant gene.
Tonometric and tonographic studies in the normal pony eye
Authors: SMITH PATRICIA J. , GUM G. G. , WHITLEY R. D. , SAMUELSON D. A. , BROOKS D. E. , GARCIA‐SANCHEZ G. A. 
Published: June 2010

SummaryTonometric and tonographic techniques were evaluated in the normal pony and compared to other species. Applanation tonometry was utilised to calculate the ocular ridigity of the normal equine eye. The mean intraocular pressure for the pony eye was established as 23.5 mm Hg (sd ±4.5). Comparing the non‐anaesthetised and anaesthetised pony eye (xylazine‐ketamine and glycerol guaiacolate) no significant change in intraocular pressure occurred (P<0.49). Mean aqueous outflow facility was 0.88 μl/min/mm Hg (sd ±0.65) which is significantly higher (P<0.01) than the canine and human species. The ocular rigidity values for the pony eye were higher which indicates that the eye is more rigid than either the canine or human eye.
Application of a standardised treadmill exercise test for clinical evaluation of fitness in 10 Thoroughbred racehorses
Authors: SEEHERMAN H. J. , MORRIS ELISABETH A. 
Published: June 2010

SummaryClinical exercise stress testing is an important diagnostic tool for evaluating exercise intolerance and degree of fitness in human athletes. The purpose of this paper was to describe the methodology necessary to perform a clinical exercise test and report the results of performance evaluations on 10 Thoroughbred racehorses using this test. The test utilised an open flow gas analysis system for ease of use with untrained horses and a fast time response lactate analyser for rapid data analysis. Exercise test measurements used to evaluate fitness included peak oxygen consumption (mean V̇O2peak = 161.9 ± 12.9 ml/kg/min), peak heart rate (mean HRpeak = 232 ± 10 b/m), peak venous blood lactate concentration (mean LAC peak = 15.2 ± 5.8 mmol/l), peak packed cell volume (mean PCVpeak = 0.64 ± 0.3 l/l) and the maximum number of steps completed (mean STEPmax = 8.7 ± 0.5 steps). The relationship between these exercise test measurements with velocity and time post exercise was also evaluated. Change in serum creatine kinase levels resulting from exercise test were minimal (mean ΔSCK = 72 ± 53 u/l).
Pulmonary artery, aortic and oesophageal pressure changes during high intensity treadmill exercise in the horse: a possible relation to exercise‐induced pulmonary haemorrhage
Authors: ERICKSON B. K. , ERICKSON H. H. , COFFMAN J. R. 
Published: June 2010

SummaryThis study investigated changes in packed cell volume (PCV), pulmonary artery and aortic pressures, and the interaction between oesophageal pressure and pulmonary artery and aortic pressures during strenuous exercise in the horse. It was hypothesised that oesophageal pressure changes summate with pulmonary artery and aortic pressures during exercise and contribute to exercise‐induced pulmonary haemorrhage (EIPH). Acute treadmill exercise (10 m/sec, 3° incline) produced increases in heart rate (HR) from 50 to 202 beats/min; mean pulmonary artery pressure (PAP) from 28 to 80 mmHg; mean aortic pressure (AP) from 108 to 157 mmHg; and PCV from 0.35 to 0.52 litres/litre. EIPH was observed in three of seven horses after treadmill exercise, but no differences in the above variables were observed between the two groups of horses. Electronic subtraction of the oesophageal pressure signal from PAP and AP signals indicated peak transmural pressures of approximately 150 mmHg pulmonary and 175 mmHg aortic pressure. The elevated PAP associated with exercise appeared related more to increased HR and less to PCV (blood viscosity) or AP (bronchial). Both pulmonary artery and aortic peak transmural vascular pressures were substantially influenced by oesophageal pressure changes; peak and mean pulmonary artery and aortic pressures were significantly higher than resting pressures, and may conceivably contribute to EIPH.
Accuracy of formulae for calculating left ventricular volumes of the equine heart
Authors: LORD P. F. , CROFT M. A. 
Published: June 2010

SummaryEchocardiography may be an accurate method of measuring left ventricular (LV) volumes and mass of the horse's heart. If so, studies of the heart size and hypertrophy would be possible. This study evaluated geometric models of the external and internal LV shapes, to determine which could be applied to echocardiographic measurements. We preserved 30 horses' hearts and measured their dimensions and cross sectional areas. These measurements were entered into seven formulae representing different geometric models of the ventricle and its chamber. We derived a correction factor to estimate the long axis as a fixed proportion of the external diameter, so that volumes could be determined from an M‐mode or a cross sectional echocardiogram. Statistical analysis of the regressions of known volumes against calculated volumes measured by water displacement, demonstrated that the ellipsoid formula using cross sectional areas was very accurate in representing the external shape of the left ventricle (slope = 1.01 r2 = 96.3) and its chamber (slope = 0.83, r2 = 94.3). Myocardial volume, measured by subtracting internal (chamber) volume from external volume, was also calculated accurately (slope = 1.01, r2 = 96.5). The ellipsoid formula using directly measured diameter was only slightly less accurate. LV mass could be calculated by applying the specific gravity of equine myocardium, 1.05, to the myocardial volume. Formulae recommended for evaluating are, with M‐mode echocardiography:and with 2D echocardiographywhere De is the external diameter, Di is the internal diameter, Ae the external area and Ai the internal area.
Effects of treadmill elevation on heart rate, blood lactate concentration and packed cell volume during graded submaximal exercise in ponies
Authors: SEXTON W. L. , ERICKSON H. H. 
Published: June 2010

SummarySix ponies performed a standardised exercise test on a motorised treadmill at each of three randomly assigned treadmill elevations (1, 4, or 7°). The exercise test consisted of four, 4 min increments of increasing treadmill speed from 1.0 to 3.4 m/sec. Heart rate, blood lactate concentration, and packed cell volume (PCV) were determined, during the last min of each exercise level, and at 4 and 12 mins post exercise. Regardless of treadmill elevation, no differences were observed in pre‐exercise heart rate (49 ± 2) beats/min), lactate (1.2 ± 0.1 mM), and PCV (0.32 ± 0.01 litres. During exercise, heart rate and PCV were highly correlated to treadmill speed and elevation. Peak exercise heart rates (determined at 3.4 m/sec) were 159 ± 10, 182 ± 5, and 216 ± 6 beats/min at 1, 4, and 7°, respectively, while peak PCVs were 0.37 ± 0.01, 0.40 ± 0.01 and 0.42 ± 0.02 lit/litre at 1, 4, and 7°, respectively. Blood lactate did not change significantly from pre‐exercise levels during the exercise test at a treadmill elevation equal to 1°, but increased markedly at 4 and 7°. Peak lactates were 1.9 ± 0.7, 5.3 ± 1.0, and 18.1 ± 1.5 mM at 1, 4, and 7°, respectively. There was a highly significant correlation between heart rate and lactate at all treadmill speeds and elevations. Therefore, during graded, submaximal exercise increasing treadmill elevation up to 7° results in increases in heart rate, blood lactate concentration and PCV comparable to those seen with increasing treadmill speed alone.
The effect of an acute hoof wall angulation on the stride kinematics of trotting horses
Authors: CLAYTON HILARY M. 
Published: June 2010

SummaryHigh speed cinematography was used to describe the stride kinematics in a group of six, sound horses subjected to two farriery treatments, designated ‘normal’ and ‘acute’ hoof angulation. Normal was defined as having the dorsal hoof wall aligned with the pastern axis, whereas the acute hoof angulation was approximately 10° lower than the normal angle for the individual horse. The acute angle was achieved by allowing the toes to grow relatively longer than the heels. The results of a multivariate analysis of variance showed significant differences between the two farriery treatments in the mode of hoof impact with the ground and the duration of breakover. The acute angulation was associated with fewer heel‐first impacts and a greater number of toe‐first impacts than the normal angulation (P<0.01). Breakover time was prolonged with the acute angulation (P<0.01). There were no significant differences between the two farriery treatments in stride length, duration of the suspension phase of the stride or duration of the stance phases of the fore or hind limbs (P>0.05). The flight arc of the toe was similar for the normal and acute hoof angles, reaching its highest point shortly after lift off, after which the toe followed a low flight path. There was an elevation of the toe in preparation for heel‐first or flat‐foot impact, but when impact was toe‐first the trace approached the ground smoothly at a more acute angle.
The role of the reciprocal apparatus in the hind limb of the horse investigated by a modified CODA‐3 opto‐electronic kinematic analysis system
Authors: VAN WEEREN P. R. , VAN DEN BOGERT A. J. , BARNEVELD A. , HARTMAN W. , KERSJES A. W. 
Published: June 2010

SummaryThe function of the reciprocal apparatus in the hind limb of the horse was studied by kinematic gait analysis. For recording purposes a modified opto‐electronic CODA‐3 kinematic analysis system was used. The raw kinematic data were corrected for skin displacement artifacts by use of recently developed correction models. It was concluded that contradictory findings about the coupling of tarsal and stifle joints by the reciprocal apparatus, when comparing in vitro and in vivo studies, can be fully attributed to artifacts due to the movement of the skin markers over the underlying bony structures, occurring in the in vivo experiments.
A quantitative analysis of skin displacement in the trotting horse
Authors: VAN WEEREN P. R. , VAN DEN BOGERT A. J. , BARNEVELD A. 
Published: June 2010

SummarySkin displacement was investigated at 16 sites in the front and hind limbs of four Dutch Warmblood horses at the trot. For visualisation of the bone under the skin, a measuring device mounted on a Steinmann pin driven into the bone under investigation, was employed. Mean displacements ranged from 8 mm (X‐displacements proximal and distal metacarpus) to 142 mm (Y‐displacement caudal part of greater trochanter). When compared with previously determined skin displacement patterns at walk, mean displacements at trot were of the same magnitude whereas the shape of the time‐displacement curve was different. The latter may be attributed to differences in relative duration of stance and swing phases between the walk and the trot.
Failure of passive immunisation by colostrum from immunised mares to protect foals against Rhodococcus equi pneumonia
Authors: Martens R. J. , Martens Judy G. , Fiske R. A. 
Published: June 2010

SummaryThe immunoprophylactic capacity of colostrum‐derivedRhodococcus equiantibodies was evaluated in pony foals experimentally infected withR. equi.Six pony mares (Group 1) were injected serially with liveR. equiduring pregnancy; a further six pony mares were not vaccinated and used as controls All (Group 2) foals were permitted to suck from their dams and the adequacy of IgG, passively transferred via colostrum, was determined by single radial immunodiffusion. The presence and relative value of R. equi specific antibodies were determined by ELISA. Mares vaccinated withR. equideveloped significantly (P<0.05) increasedR. equiantibody levels, and the principal foals from these mares had specific antibody values that were significantly (P<0.01) higher than control foals.Rhodococcus equiwere aerosolised into a caudal lung lobe of all foals at seven days of age. Clinical signs, haematological alterations, immune responses and thoracic radiographs were monitored. Foals were subjected to euthanasia and complete post mortem examinations were performed. All foals developed pneumonia as evidenced by clinical and radiographic signs. The survival rate for Group 1 foals did not differ significantly from that of control foals. Two of the six foals in each group survived the bacterial challenge. Also, there were no significant differences between groups for duration of survival, peak febrile responses, duration of fever, time from infection to onset of fever, or peak concentrations of leucocytes and neutrophils. Post mortem examinations of four foals from each group, destroyed approximately three weeks post infection because of terminal disease, revealed severe pyogranulomatous pneumonia involving primarily the caudal portion of one lung. One control foal had miliary pyogranulomatous lesions in both lungs.Rhodococcus equiwas cultured from the pulmonary lesions in these foals. Two principal and two control foals that recovered from the infections had mild pulmonary fibrosis at three months post infection.Rhodococcus equiwas not cultured from any of these foals at necropsy. The results of this investigation suggest that passive immunisation of newborn foals, by ingestion of colostrum derivedR. equispecific antibodies, does not provide adequate protection against experimental infection withR. equi.
Therapeutic effects of immune plasma in foals with Rhodococcus equi pneumonia
Authors: Chaffin M. K. , Martens R. J. , Martens Judy G. , Fiske R. A. 
Published: June 2010

SummaryThe immunotherapeutic efficacy of specific immune plasma was evaluated in pony foals infected experimentally withRhodococcus equi. ViableR. equiwere aerosolised into the right caudodorsal lung of 10 foals at seven days of age. Immune plasma, produced by repeated parenteral administration of viableR. equito an adult donor gelding, was harvested and frozen. Group 1 (4 foals) and Group 2 (6 foals) foals received lactated Ringer's solution and immune plasma, respectively, at seven and nine days post infection. Clinical signs, haematological alterations, immune responses and thoracic radiographs were monitored throughout the study. All foals were destroyed and complete post mortem examinations were performed. All foals developed pneumonia as evidenced by clinical and radiographic alterations. Immune plasma had no significant effect on survival rate, length of survival, temperature response or peripheral blood concentrations of leucocytes, neutrophils or fibrinogen. Enzyme‐linked immunosorbent assay values forR. equi‐specific antibody and serum concentrations of IgG were significantly greater in Group 2 foals following treatment with immune plasma. Post mortem examination of three Group 1 and four Group 2 foals, destroyed because of terminal disease, revealed severe pyogranulomatous pneumonia. The two surviving Group 2 foals were free of gross pulmonary lesions and had minimal microscopic scar formation three months post infection; whereas the one surviving Group 1 foal had a large, encapsulated, caseonecrotic pulmonary mass three months post infection. This study demonstrates that the parenteral administration ofR. equiimmune plasma to foals seven days after experimental infection withR. equidoes not alleviate the clinical signs nor alter the course of disease.