Development and evaluation of an endoscopic technique permitting rapid visualization of the cardiac region of the porcine stomach.

Our study was designed to ascertain whether a flexible videoscope could be used to efficiently monitor ulcers of the pars esophagea in a large group of grower-finisher swine. Gastroscopy was performed on 2 separate occasions in 32 pigs following anesthesia with intravenous pentobarbital, and ulcers of the pars esophagea were subjectively graded. The pigs were then necropsied. Grades from the second endoscopic examination were compared for agreement with grades derived from gross inspection of the pars esophagea at necropsy, and with grades derived from histopathologic examination of sections of the same region. The pars esophagea was adequately visualized in all endoscopic examinations. The average duration of each examination, from anesthetic induction, was approximately 8 min. Gastroscopy permitted appreciation of a wide range of focal and diffuse superficial and deep ulcerative lesions of the pars esophagea, but failed to unequivocally identify parakeratosis of the pars esophagea. Agreement between endoscopic and subsequent necroscopic and histopathologic gradings of ulcerations was poor. We concluded that the use of a flexible videoscope permitted rapid inspection of the pars esophagea, and was therefore a practical method of experimentally monitoring the progression of spontaneous gastric ulcers in pigs. We also postulated that the poor agreement between endoscopic and postmortem findings occurred because endoscopy was possibly more sensitive at detecting small and superficial ulcerations. However, further studies are needed to verify the accuracy of endoscopic diagnosis of gastric ulcers in the live pig.     

Corneal concentrations and preliminary toxicological evaluation of an itraconazole/dimethyl sulphoxide ophthalmic ointment

The objectives of this study were to determine the concentration of itraconazole achieved in corneal tissue and aqueous humour after topical application of a 1% itraconazole ointment; to determine the effect of including dimethyl sulphoxide (DMSO) in the ointment on achievable ocular tissue itraconazole concentrations; and to assess if any gross or histopathologic ocular toxicity results from the topical application of 1% itraconazole with or without the addition of DMSO.
The experimental trial consisted of 6 horses considered to have normal eyes. Each horse had one eye treated with 0.3 mL of 1% ultra-micronized itraconazole ointment and the fellow eye with 0.3 mL of 1% itraconazole/30% DMSO ointment. The ointment was applied every 6 h for a total of 28 treatments. Both ointments were well tolerated and no gross or histopathologic abnormalities developed during the trial.
Corneal tissue and aqueous humour concentrations of itraconazole were determined using high performance liquid chromatography. Corneal tissue concentration averaged 1.1 (± 0.4) μg/g in horses treated with the 1% ultra-micronized itraconazole ointment and 7.9 (± 3.3) μg/g for those treated with the 1% itraconazole/30% DMSO ointment; there was a statistically significant difference between ointments ( P = 0.005) No itraconazole could be detected in the aqueous humour in either treatment group.     

Laparoscopic Cryptorchid Castration in Standing Horses

Objective — This article describes a new technique for laparoscopic cryptorchid castration in standing horses. Study Design — Prospective study. Animals or Sample Population — Eight horses aged 11 months to 3 years and weighing between 300 and 643 kg. Methods — Food was withheld for 24 to 36 hours, and then horses were sedated with detomidine HC1 (0.02 to 0.03 mg/kg) and butorphanol tartrate (0.02 mg/kg). The paralumbar fossa region was desensitized with 2% mepivacaine in an inverted “L” pattern and caudal epidural anesthesia was administered with either xylazine (0.18 mg/kg diluted to 10 to 15 mL with 0.9% sodium chloride) or a combination of 2% mepivacaine and xylazine (0.18 mg/kg). Initial laparoscopic exploration was performed from the left flank; in three horses, right flank laparoscopy was needed to complete the procedure. The spermatic cord was ligated within the abdomen with one or two sutures of 0 polydioxanone suture, and the testis or testes removed through a flank incision. Results — In five horses with no palpably descended testes, standing laparoscopy was the only procedure performed, whereas in two horses, the abdominal testis was removed laparoscopically, and the descended testis was removed under short acting anesthesia. In one horse, with nonpalpable testes, it was determined by laparoscopic observation that the testes were in the inguinal canal, and castration was performed under general anesthesia. No surgical or postoperative complications were noted. The right side of the abdomen, and especially the right vaginal ring, could be easily observed from the left side by passing the laparoscope through a small perforation in the mesocolon of the descending colon or by elevating the descending colon with an instrument or by use of an arm in the rectum. Conclusions — The standing laparoscopic approach combined with or without short-acting anesthesia to remove the descended testis is easily performed. Clinical Relevance — This approach will provide surgeons with another option to castrate cryptorchid stallions.     

A multivariable prognostic model for equine colic patients

A survey of 1965 equine colic cases was conducted from August 1985 to July 1986 ten equine referral hospitals located througout the U.S.A. Two-thirds of the cases were randomly selected for model development (1336), while the remaining cases (629) were used only for subsequent validation of the model. The following outcomes were defined: (1) died or killed prior to discharge from the hospital; or (2) alive at the time of discharge. Only variables which were significant (P<0.05) in an initial bivariate screening procedure and for which there were less than 400 missing values were considered in the multivariable modelling. A multivariable logistic regression model was constructed using a stepwise algorithm. The model used 666 cases and included the following variables: peripheral pulse (normal or weak), pulse rate, surgical or medical treatment, packed cell volume, self-inflicted trauma (absent or present) and capillary refill time. For each horse in the validation data set which had the appropriate variables recorded (n=335), the estimated expected probability of death (expected value) was calculated using the logistic regression equation. Using Bayes theorem, the post-test probability was calculated from the expected value (an estimate of the test odds) and the present probability (the case-fatality rate at each institution). Nomograms of predictive values for different case-fatality rates and expected values were constructed. Hosmer-Lemeshow goodness-of-fit statistics indicated that the model fitted the model data set well but the validation set poorly. However, when the observed case-fatality rates were compared with the average post-test probabilities for 0.10 increments of post-test probability, qualitatively, the model's performance was better.     

Intraruminal administration of milk in the calf as a model for ruminal drinking: Morphological and enzymatical changes in the jejunal mucosa

In order to develop a calf model for studying the syndrome of ruminal drinking (RD) in veal calves, three dual-fistulated calves were used to test the effect of intraruminal administration of milk replacer on the jejunal mucosa. Biopsies of the proximal jejunal mucosa were taken through a jejunal fistula and the mucosal morphology and the activities of two brush border enzymes, lactase and alkaline phosphatase, were determined.Means of villus length and brush border enzyme activities decreased during the period of intraruminal administration of milk. The hyperplastic villus atrophy in this model was similar to that found in chronic RD patients in previous studies. This could not be associated with isolation of pathogenic micro-organisms from the faeces and is probably the consequence of the intraruminal milk feeding procedure itself.Clinical recovery from the signs of RD occurred rapidly after intraruminal administration of milk ceased and was followed by restoration of villus length and brush border enzyme activities 3–4 weeks later.     

Airway hypersensitivity induced by Ascaris suum extract in New Zealand Romney sheep

Sheep from local farms with and without previous exposure to pigs were tested for their skin and airway responses to a commercial Ascaris suum antigen. There was an immediate reaction to intradermal injection of the antigen in 90% of 101 sheep. A bronchial provocation test by aerosol of the same antigen was undertaken on 43 of the sheep with a positive skin reaction. About 70% of sheep showed an immediate airway response to the antigen as an aerosol, reflected as a significant increase in airway resistance and/or decrease of dynamic lung compliance. The mean peak airway resistance and mean lowest dynamic lung compliance were 165% above and 61% below their baselines, respectively. No significant changes were recorded when the same animals were given an aerosol of phosphate buffered saline. Similarly, no correlation was found between the degree of skin reaction and the magnitude of bronchoconstriction (p>0.05). The sheep with previous exposure to pigs showed no significant differences in airway responses to antigen challenge, although they showed significantly greater skin reactions than those without exposure to pigs. These results indicate that the majority of Romney sheep in the Manawatu have a natural skin and airway sensitivity to A. suum antigen and may therefore be used as an animal model to study human airway hypersensitivity. The origin of this sensitivity has yet to be determined.     

Interstitial lung disease in feline immunodeficiency virus (FIV) infected cats

Postmortem bronchoalveolar lavage of feline immunodeficiency virus-infected cats indicated an alveolitis process, and histological examination of their lungs confirmed the occurrence of alveolitis, parenchymatous lymphoplasmocytic infiltration and myomatosis. Similar lymphoid interstitial pneumonitis has been described in human and animal lentiviral diseases: lymphocytic interstitial pneumonitis in hiv-1-infected human beings, and maedi in sheep infected by the maedi-visna virus. Such lymphoid interstitial pneumonitis may thus be a common feature of lentiviral infections.     

Assessment of parental genomic proportions in crossbred chickens by DNA fingerprints

SUMMARY: Starting with the second crossbred generation, parental genomic-proportion lines in individuals deviate considerably from expectation. These individual variations offer the potential to increase the efficiency of crossbreeding programmes. DNA fingerprinting was established as an approach, to quantify the genomic contribution of the parental lines in individuals of two crossbred generations. For this purpose, line-specific bands were identified in representative banding patterns of pooled DNA from purebreds. The representative banding patterns obtained with eight combinations of restriction enzymes HinfI and AluI, and oligonucleotide probes [CA]8, [CAC]5, [GGAT]4, and [GACA]4, contained between nine and 14 line-specific bands. The estimation of the proportion was based on the relative proportion of line-specific bands of one parental line in banding patterns of crossbreds. This was first done in F1 individuals with a definite 50% genomic proportion of each parental line, to determine the accuracy of the approach. The mean value, 51.0 ± 0.34%, observed in 45 F1s using all eight combinations of enzymes and probes, of genomic contribution of one parental line, was close to the theoretical value of 50%. In 24 animals of the BC1, considerable shifting of the parental genomic proportion was observed. ZUSAMMENFASSUNG: Sch?tzung der Genomanteile bei Hühnern verschiedener Kreuzungsstufen durch DNA-Fingerprinting Von der ersten Rückkreuzungsgeneration an treten erhebliche, individuelle Verscheibungen in der Verteilung der Genomanteile der parentalen Ausganslinien vom Durchschnitt auf. Diese individuelle Variation stellt ein Potential zur Steigerung der Effektivit?t von Kreuzungszuchtprogrammen dar. Mit der vorliegenden Arbeit wird eine Untersuchungsmethode zur direkten Quantifizierung der Genombeitr?ge der parentalen Ausganslinien bei Individuen verschiedener Kreuzungsstufen durch DNA fingerprints vor gestellt. Dazu wurden in für die Ausgangslinien repr?sentativen Bandenmustern aus DNA-Gemischen linienspezifische Banden identifiziert. Die repr?sentativen Bandenmuster wurden mit den Restriktionsenzymen HinfI and AluI sowie den Oligonukleotidsonen [CA](8) , [CAC](5) , [GGAT](4) , und [GACA](4) erzeugt und enthielten 9-14 linienspezifische Banden. Die Bestimmung der parentalen Genomanteile beruhte auf der Identifizierung linienspezifischer Banden in den Bandmustern von Kreuzungsindividuen und der anschlie?enden Berechnung des relativen Anteils an für eine parentale Linie spezifischen Banden. Um die Genauigkeit der Untersuchungsmethode zu evaluieren, wurde sie zun?chst bei F(1) Tieren angewandt, die einen Anteil von jeweils 50% der elterlichen Linien aufweisen müssen. Der Durchschnittswert berechnet über alle 45 F(1) Individuen und alle acht Kombinationen von Enzymen und Sonden betrug 51,0 ± 0,34% Genomanteil der einen parentalen Linie und lag somit nahe dem theoretischen Wert von 50%. Bei 24 Tieren der R1 konnte eine beachtliche Verschiebung der Genombeitr?ge der parentalen Ausgangslinien gezeigt werden.     

Effect of natural zeolite on yolk: Albumen ratio in hen eggs

1. The egg yolk: albumen (Y:A) ratio during the laying year was investigated in a commercial strain (Hisex) when natural zeolite was added to a layer's diet. 2. Dietary natural zeolite (NZ) increased both egg weight and albumen weight, while yolk weight was not significantly affected. 3. The Y:A ratio was less (more albumen) in eggs laid by hens on zeolite treatments. It was concluded that by feeding NZ it is possible to alter the Y:A ratio.     

Influence of high dietary vitamin E supplementation on egg production and plasma characteristics in hens subjected to heat stress

1. The effects of different dietary concentrations of vitamin E (alpha-tocopherol acetate) were investigated in 2 experiments on laying hens exposed to chronic heat stress at 32C. 2. In the first experiment, egg production and plasma concentrations of calcium and egg yolk precursors were measured in 24 hens before, during and after a stress period of one week and fed on diets containing 10 or 500 mg vitamin E/kg. 3. In the second, larger experiment, egg production and food intake were measured in 300 hens housed in 2 temperature-controlled rooms and fed on diets containing 10, 125 or 500 mg vitamin E/kg. Birds in room 1 were stressed from 24 to 28 weeks of age and those in room 2 from 32 to 36 weeks. 4. In experiment 1, egg production and egg weight were significantly higher (72.6 vs 51.2%, P < 0.05 and 66.6 vs 63.1 g, P < 0.005 respectively) during and after the period of stress in the group given 500 mg vitamin E/kg. Plasma concentrations of calcium, vitellogenin (zinc) and VLDL (triglyceride) were also higher in this group. 5. In experiment 2, egg production was significantly higher (65.4 vs 56.2%, P < 0.05) during and after the period of heat stress in birds in room 1 fed on the diet containing 500 mg vitamin E/kg. Egg production was also higher (49.9% vs 44.7%) on this treatment during the stress period in room 2, though the difference was not significant (P < 0.10). Egg weight and food intake were unaffected by treatment in either room. 6. It is concluded that dietary supplementation with extra vitamin E can, at least in part, alleviate the adverse effects of chronic heat stress in laying hens, perhaps by maintaining the supply of egg precursors in plasma.