bluuebunny/crossref_metadata_2025_split huggingface dataset:
Videoendoscopic evaluation of the mare's uterus: III. Findings in the pregnant mare
Authors: ALLEN W.R. , BRACHER VERENA 
Published: April 2010

SummaryDuring a 5‐year period 65 Pony and 20 Thoroughbred pregnant mares were subjected to videoendoscopic hysteroscopy from 10 to 266 days of gestation. The aims of these examinations were to 1) observe foetal and placental developmentin vivo(60 Pony and 10 Thoroughbred mares); 2) eliminate one of unicornuate twin conceptuses (9 Thoroughbred mares); 3) recover embryonic foetal and placental tissues non‐surgically for experimental purposes (47 Pony mares); 4) induce focal separation of the placenta in late gestation as an experimental model of placentitis (5 pony mares and 1 Thoroughbred mare). It was possible to view the embryo and all constituent extra‐embryonic membranes of the conceptus between Days 10 and 87 of gestation without having to perforate the allantochorion. This allowed study of physiological processes such as the coordinated uterine contractions responsible for conceptus motility between Days 7 and 17, active foetal movements, which began as early as Day 34, and invasion of chorionic girdle cells into the endometrium, which occurred between Days 34 and 38. From Day 90, vision of the foetus was reduced or prevented by the increased thickness of the allantochorion. Transendoscopic recovery of the conceptus was successful in all of 10 mares under 30 days of gestation, whereas only 10 of 18 attempts between Days 30 and 45 produced the conceptus without resorting to uterine lavage after initial rupture of the allantochorion. All 9 attempts to eliminate one of unilateral twin conceptuses were unsuccessful and the technique was abandoned as clinically unsuitable. Nevertheless, 9 of 22 (41%) single conceptuses remained viable after one or more hysteroscopic examinations. This did not seem to be influenced by a variety of anti‐abortion treatments administered.
Milk and water intakes of foals sucking grazing mares
Authors: MARTIN R. G. , McMENIMAN N. P. , DOWSETT K. F. 
Published: April 2010

SummaryIntakes of milk and milk nutrients were determined for 8 foals at 11–18 days of age and for 10 foals at 30–44 days and 60–74 days of age while sucking grazing mares. Water intakes (sources other than milk) of the foals were determined at 30–44 days and 60–74 days of age. Five of the 10 mares were fed a protein supplement (24% crude protein) in addition to grazing during the stud season. The protein supplement did not influence foal intakes of milk and milk nutrients, milk composition, weight gains of the mares or the growth rate of the foals. Foal milk intakes increased (P<0.05) from 16.9 kg/day at 11–18 days to 18.1 kg/day at 60–74 days of age. The water intakes of the foals increased (P<0.01) from 3.9 kg/day at 30–44 days to 5.5 kg/day at 60–74 days of age. Total fluid intakes per kg foal liveweight were 246, 202 and 172 g at 11–18, 30–44 and 60–74 days of age, respectively. For each kg of weight gain, foals consumed 12.8, 15.7 and 16.4 kg milk at 11–18, 30–44 and 60–74 days of age. Stage of lactation had a significant effect on the total solids, lactose and protein content of milk. The fat and gross energy content of milk remained constant.
Treatment of respiratory infections in horses with ceftiofur sodium
Authors: FOLZ S. D. , HANSON B. J. , GRIFFIN A. K. , DINVALD L. L. , SWERCZEK T. W. , WALKER R. D. , FOREMAN J. H. 
Published: April 2010

SummaryCeftiofur sodium was evaluated as a therapy for respiratory infections in horses. This cephalosporin antimicrobial was administered intramuscularly every 24 h and at a dose of 2.2 mg/kg (1.0 mg/lb) of body weight. The efficacy of ceftiofur sodium was compared with that of a positive control drug, ampicillin sodium (recommended dose of 6.6 mg/kg [3 mg/lb], given every 12 h). Both treatments were continued for 48 h after clinical symptoms were no longer evident (maximum of 10 days). Fifty‐five (55) horses with naturally acquired respiratory infections were included in the study; 28 were treated with ceftiofur and 27 with ampicillin. Clinical improvement was recorded for 92.9% of the patients treated with ceftiofur and 92.6% of the animals receiving ampicillin. Both therapies reduced body temperatures to an afebrile level after 2 days of treatment. Complete recovery/cure was noted for 78.6% of the ceftiofur patients and 59.3% of the horses treated with ampicillin. Supporting variables (depression/malaise, respiration/dyspnoea, nasal discharge) were assessed and these also substantiated the effectiveness of the treatments. Both antibiotics were well tolerated. Neither pain nor swelling were noted at the ceftiofur injection site(s). None of the animals developed diarrhoea. Data from this study indicated that ceftiofur sodium is an effective and safe treatment for respiratory infections in horses.
Tearing of the medial palmar intercarpal ligament in the equine midcarpal joint
Authors: McILWRAITH C. W. 
Published: April 2010

SummaryTearing of the medial palmar intercarpal ligament is described in 45 intercarpal (midcarpal) joints in 42 horses (37 racehorses, 5 non‐racehorses). Of the 37 racehorses, there were 20 Quarter Horses, 14 Thoroughbreds and 3 Standardbreds. The patients had been referred for arthroscopic surgery for removal of osteochondral chip fragments that had been diagnosed radiographically or diagnostic arthroscopy of a persistent carpal problem. The problem was unilateral in 39 horses and bilateral in 3. The presenting clinical signs were lameness and/or persistent synovial effusion. In one instance, the presenting complaint was haemarthrosis. Osteochondral chip fragments were present in the joint affected with tearing in 23 horses. In 6 horses in which osteochondral fragments were present in other joints, the degree of synovial effusion was greatest in the midcarpal joint with ligamentous tearing. In most of the 22 midcarpal joints where carpal chip fragmentation and ligamentous tearing were present concomitantly, the degree of clinical compromise was greater than normally seen with that degree of osteochondral fragmentation. A ligament was designated as torn when a defect was present in the ligament. This usually took the form of frayed fibres suspended in the irrigating solution, presenting a transverse type of defect in the dorsal aspect of the lateral portion of ligament. However, longitudinal tearing was present in 1 case and tearing was noted in the palmar aspect of the ligament in 2 other cases. The shredded fibres were trimmed in most cases and this allowed better definition of the amount of ligament considered to be torn. The degree of damage ranged from 10% to 100% of the width considered to be torn. A total loss of integrity was diagnosed in 2 cases. The degree of tearing was estimated at 70–90% in 6 joints, 50% in 11 joints, 30% in 7 joints, 20–25% in 7 joints, and 10–15% in 9 joints. Long‐term follow‐up was obtained for 31 horses and 17 had successful and 14 unsuccessful results. Of the horses with successful results, 13 were estimated as having 30% or less damage to the ligament and 3 horses with 50% damage to the ligament raced successfully after treatment with intra‐articular corticosteroids. One horse with >30% damage was considered to be successful without the use of intra‐articular corticosteroids. In the 14 horses with unsuccessful results, all but 2 had 50% or more estimated damage to the medial palmar intercarpal ligament. Of the 2 exceptions, 1 had 30% damage but also had a sagittal fracture of the third carpal bone and the second horse's lack of success was considered to be unrelated to the carpus.
Healing of full‐thickness cartilage compared with full‐thickness cartilage and subchondral bone defects in the equine third carpal bone
Authors: HANIE ELIZABETH A. , SULLINS K. E. , POWERS B. E. , NELSON P. R. 
Published: April 2010

SummaryThe effect of lesion depth on the quality of third carpal bone cartilage repair was examined. A 1‐cm diameter articular defect penetrating the calcified cartilage in one limb and the subchondral bone plate in the opposite limb was created in the radial facet of the third carpal bones. Clinical and xeroradiographic examinations were performed every 4 weeks until 4 months (3 horses) and 6 months (3 horses) after surgery. The synovial membrane, non‐opposing articular surfaces and articular defects were examined grossly, histologically and histochemically. Grossly, deeper defects contained thicker, whiter tissue, but both joints contained generalised degenerative changes. Defects extending through calcified cartilage were filled deeply by fibrocartilage and superficially by fibrous connective tissue. Defects extending through subchondral bone were consistently filled with hyaline‐like cartilage in the depths of the lesion, fibrocartilage in the intermediate layer and fibrous connective tissue superficially. The results indicate that subchondral bone is the source of hyaline‐like cartilage repair tissue and suggest that quality of healing of cartilage defects may be improved by penetrating the subchondral bone plate. It also appears that the synovitis associated with the procedure must be controlled before the procedure can be advocated for treatment of clinical cases.
Intravenous catheterisation of foetus and mare in late pregnancy: management and respiratory, circulatory and metabolic effects
Authors: TAYLOR POLLY M. , SILVER MARIAN , FOWDEN ABIGAIL L. 
Published: April 2010

SummaryThe uterine and umbilical vessels of 12 pregnant ponies were catheterised to study foetal metabolism. The effects of this procedure on maternal and foetal cardiovascular, respiratory, metabolic and adrenocortical activity were monitored during and after surgery. Premedication with acepromazine ‐butorphanol‐detomidine was followed by induction of anaesthesia with detomidine and ketamine and maintenance, using mechanical ventilation, with halothane in oxygen and nitrous oxide. Mean maternal arterial blood pressure was >70 mmHg during anaesthesia and arterial oxygen tension remained over 100 mmHg. The foetuses were adequately oxygenated but were hypercapnic and lacticacidaemic. Most maternal and foetal blood gases and metabolites had returned to normal by 24 h, although foetal plasma lactate fell more slowly. The maternal adrenocortical discharge was less severe than reported previously and plasma Cortisol had fallen to basal levels by 48 h after surgery. Foetal plasma Cortisol remained low and did not change during or after surgery. Arterio‐venous metabolite and gas tension differences across the uterine and umbilical circulations were slightly greater at operation than in the recovery period, suggesting that uteroplacental perfusion may have been impaired during surgery. Post‐operative recovery of the mare and foetus was satisfactory and subsequent problems associated with the foetal catheters were not related to the anaesthesia or surgery.
Fractures of the lateral malleolus of the tibia in 16 horses
Authors: WRIGHT I. M. 
Published: April 2010

SummaryClinical and radiological features of 16 horses with fractures of the lateral malleolus of the tibia are reported. The paper describes surgical techniques used, results obtained and discusses justification for removal. Fourteen fractures were unilateral and two bilateral. There was no left:right disparity. The history included a known traumatic incident in 14 cases. All animals had a tarsocrural joint effusion and 10 had palpable thickening of the lateral collateral ligaments. Crepitus was also palpable in 10 horses. The fracture was identified in all dorsoplantar and 14 of 18 dorsomedial‐plantarolateral oblique radiographic projections. Nine fractures were simple and 9 comminuted. All fractures were removed via a tarsocrural arthrotomy. Approaches were dorsolateral in 14 joints, plantarolateral Ural in 3 and dorsolateral and plantarolateral in 1. After an ascending exercise programme horses returned to work 6 months after surgery: 15 horses were free of lameness after 17–62 months, with 13 animals performing at a level similar to pre‐injury standard.
Effects of hypoxia and azotaemia on the pharmacokinetics of amikacin in neonatal foals
Authors: GREEN S. L. , CONLON P. D. , MAMA K. , BAIRD J. D. 
Published: April 2010

SummaryThe effects of hypoxia and azotaemia on the pharmacokinetics of amikacin were evaluated in 20 full‐term neonatal critically ill foals which required 24‐h supportive care, antibiotics and dextrose‐supplemented polyionic fluids given intravenously, nasal insufflation with oxygen and nutritional supplementation. There was no association between sepsis score or survival and pharmacokinetic parameters. Concurrent hypoxia and azotaemia were associated with significantly decreased clearance and increased peak and trough serum concentrations of amikacin; however, peaks or troughs did not exceed toxic values. Derangements in serum peak, trough and clearance values, which were present on admission, persisted over the 6‐day duration of this study. Daily monitoring of serum amikacin concentration revealed a tendency to underdose (particularly in foals receiving aggressive fluid therapy), which necessitated increasing the dose/kg body weight (9–12 mg/kg) and increasing the dose interval (10–12 h) in 40% (8/20) of the cases, so that blood concentrations of amikacin could be maintained within the target range of 3–15 μg/ml. Amikacin‐induced nephrotoxicity was not indicated by conventional laboratory testing, nor was it strongly suspected after examination of post mortem lesions.
Nutrient utilisation by the hindlimb of Thoroughbred horses at rest
Authors: PETHICK D. W. , ROSE R. J. , BRYDEN W. L. , GOODEN J. M. 
Published: April 2010

SummaryNutrient uptake by the hindlimb was investigated utilising the arteriovenous difference technique in 5 Thoroughbred horses fed to maintenance a diet of 100% roughage or 52% oat grain and 48% roughage. Arterial blood was obtained from a catheter inserted into the carotid artery while venous blood was simultaneously collected from a catheter placed into the iliac vein via the medial saphenous vein. The arteriovenous difference for glucose was significant and represented a mean extraction of 10 ± 1% with no effect of diet. If fully oxidised, glucose uptake (corrected for lactate and pyruvate arteriovenous difference) was sufficient to account for 78 ± 13% or 107 ± 15% of the oxygen consumed by the hindlimb in horses fed a roughage or 52% oat grain diet respectively. Acetate was also a major metabolite of the hindlimb, showing a 39 ± 5% extraction with no effect of diet. However, the 52% oat grain diet did induce a significant decline in the concentration of acetate in arterial blood. The potential contribution to oxidation in the hindlimb was significantly reduced from 32 ± 4% in horses fed roughage to 21 ± 3% when fed 52% oat grain. D‐3‐Hydroxybutyrate uptake could account for 9 ± 1% of the oxidation by the hindlimb with no effect of diet. The technique for measuring nutrient uptake across the hindlimb using the arteriovenous difference is relatively simple and would be valuable in investigating fuel use by muscle during exercise.
Effect of carnitine supplement to the dam on plasma carnitine concentration in the sucking foal
Authors: BENAMOU AGNES E. , HARRIS R. C. 
Published: April 2010

SummaryThe changes in carnitine in plasma and milk during the first 3 months of lactation were studied in 14 broodmares and their foals. Six of the mares (Group S) were given a supplement of 10 g carnitine split between the morning and evening feeds, starting 2 weeks before birth.At birth the plasma carnitine concentration in Group S mares was about twice that in Group NS mares (no supplement). In both groups the concentration initially declined in the days after birth. Whilst this trend was reversed in Group S mares, the concentration in Group NS mares remained at a reduced level for the remainder of the study. Milk concentrations declined continuously over the monitoring period in both groups. There was no apparent relationship between milk and plasma concentrations. Despite this the milk concentration tended to be higher in Group S than in Group NS mares although differences were not significant. There was an immediate drop in the plasma concentration in foals after birth which was reversed in foals of Group S mares but not in those of Group NS mares. There were no apparent side effects of carnitine supplementation.
The correlation of running ability and physiological variables in Thoroughbred racehorses
Authors: HARKINS J. D. , BEADLE R. E. , KAMERLING S. G. 
Published: April 2010

SummaryThe running abilities of 25 Thoroughbred racehorses were measured at distances of 1200, 1600 and 20000 m. Various physiological variables were measured subsequently on the treadmill and correlated with running speed. There was a negative correlation for running speed with the velocity (VLa4) and work rate (WLa4) at which blood lactate reaches a steady‐state concentration of 4 mmol/litre and a positive correlation with peak plasma lactate, suggesting that plasma lactate concentrations of faster horses rise more rapidly and to higher levels than do those of slower horses. The correlation between running speeds and heart rates (HR) was stronger for unfit than fit horses, suggesting that cardiovascular effects of training are more beneficial to slower horses. The significant correlation between running speeds and V200 suggests that the HR of faster horses increases more rapidly than in slower horses performing similar exercise. The correlation of running speeds and O2max suggests that the HR of faster horses increases more rapidly than in slower horses performing similar exercise. The correlation of running speeds and VO2max suggests that faster horses utilise more oxygen during maximal intensity exercise. The correlation of running speeds with minimum pH and minimum HCO3− suggests that faster horses maintain speed at higher hydrogen ion (H+) concentrations. Correlations between running speeds and the measured variables were consistently stronger for the longer distance runs. Because VLa4 and WLa4 were obtained during sub‐maximal exercise, these variables were determined to be the best correlates of running performance.
Advancing the time of ovulation in the mare with a short‐term implant releasing the GnRH analogue deslorelin
Authors: MEINERT C. , SILVA J. F. S. , KROETZ I. , KLUG E. , TRIGG T. E. , HOPPEN H. O. , JÖCHLE W. 
Published: April 2010

SummaryA small, biocompatible and short‐term implant releasing 1.5 mg or 2.25 mg of the GnRH analogue deslorelin was evaluated in 140 Hanoverian (warm blooded) mares during the 1990 breeding season (Study I). Mares in oestrus and with a follicle 40 ± 2 mm in diameter were assigned alternately to treatment (70) or remained as untreated controls. Implants were administered subcutaneously, and intervals to ovulation determined by rectal examination and ultrasound at 12‐h intervals. Since results with both doses of deslorelin were similar, data were pooled. Deslorelin implantation resulted in ovulations in 65 of 70 mares within 48 h (93%), while only 5 of 70 control mares ovulated within the same time period (7%) (P<0.01). Most induced ovulations (63%) occurred 36–48 h after implantation. In Study II, 4 groups of 12 Hanoverian mares each were treated with 3,000 or 5,000 iu hCG, or a 2.25 mg deslorelin implant, or received placebo. All treatments resulted in 100% ovulations within 48 h, versus 25% ovulations in controls (P<0.01), and 63%, 75% and 86% of these ovulations occurred 36–48 h after treatment with 3,000 and 5,000 iu hCG and deslorelin respectively.Hormonal response to deslorelin in treated mares, sampled every 12 h, consisted of elevations of FSH and LH concentrations of >200% and >300% baseline values at 12 h (P<0.001), of 67% and 79% at 24 h (P<0.01) and of 35% and 49% at 48 h (P<0.05), respectively. No local reactions at the implantation site were observed.
A comparison of responses to analgesia of the navicular bursa and intra‐articular analgesia of the distal interphalangeal joint in 59 horses
Authors: DYSON SUE J. , KIDD LISA 
Published: April 2010

SummaryAnalgesia of the distal interphalangeal (DIP) joint and of the navicular bursa was performed independently in the lame or lamer forelimb of 59 horses, in which lameness was significantly improved by perineural analgesia of either the palmar digital or palmar (abaxial sesamoid) nerves.In 3 horses no improvement was detected. Lameness was improved by analgesia of the DIP joint but there was no response to analgesia of the navicular bursa in 3 horses. In 12 horses, lameness was improved by analgesia of the navicular bursa but intra‐articular analgesia resulted in no change. Forty‐one horses responded both to analgesia of the navicular bursa and intra‐articular analgesia of the DIP joint. Synovial fluid was retrieved from all DIP joints but from only one navicular bursa. It is suggested that a positive response to analgesia of the DIP joint does not necessarily imply that pain arises from the jointper se, but a positive response to intra‐bursal analgesia probably reflects pathology of the bursaper se, the navicular bone and/or supporting ligaments and/or the DDFT.Radiographic abnormalities of the navicular bone in the lame or lamer limb were detected in 35 horses, all of which showed some response to analgesia of the navicular bursa. In 25 of these horses (71%) changes were only identifiable in the palmaroproximal‐palmarodistal oblique views. There was a higher incidence of radiographic abnormalities of the navicular bone in horses in which the response to intraarticular analgesia of the DIP joint was similar (70%) to, or greater (71%) than analgesia of the navicular bursa, compared with the groups in which there was no response (58%) or a lesser response (62%) to intra‐articular analgesia.The front feet of 6 horses were examinedpost mortem. All horses had pathological abnormalities of the flexor surface of the navicular bone of the lame or lamer limb and in 5 there was associated fibre damage of the opposing deep digital flexor tendon. No abnormalities of the DIP joint were identified.We suggest that, when possible, if foot pain is suspected, the following analgesic techniques should be performed in sequence, but on different occasions: (1) perineural analgesia of the palmar digital (and when necessary palmar [abaxial sesamoid]) nerves; (2) analgesia of the DIP joint; and (3) analgesia of the navicular bursa.