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Abstract

Objective—To evaluate the efficacy of an orally administered vaccine of Mycoplasma hyopneumoniae that was prepared by spray drying or solvent evaporation.

Animals—Thirty 6-week-old, crossbred, specificpathogen- free (SPF) pigs.

Procedure—Pigs were randomly allocated into 5 groups and housed in an SPF facility. Pigs in 2 groups (groups AQ and CAP) were fed M hyopneumoniae enteric-coated vaccine on days 0, 10, and 20. A third group (group IM) received an IM injection of M hyopneumoniae vaccine with aluminium hydroxide as an adjuvant on days 0, 10, and 20. The last 2 groups (nonvaccinated- challenged [NV-C] and nonchallenged [NC]) were fed a sham treatment. All 24 pigs in groups AQ, CAP, IM, and NV-C were challenge exposed with 5 ml of a 10% pneumonic lung suspension administered on day 40 via intubation of the trachea. All pigs were slaughtered and the lungs removed and examined for lesions on day 68.

Results—In vitro studies indicated that these 2 microencapsulation techniques formed an effective shell and protected mycoplasmal antigen from gastric acid. Results of inoculation and challenge tests indicated that microencapsulated M hyopneumoniae were sufficiently potent to induce an immune response and provide good protection.

Conclusions and Clinical Relevance—Orally administered microencapsulated M hyopneumoniae vaccines induced an immune response and reduced the severity of lung lesions in challengeexposed pigs. Results suggest that this novel method can be applied to other antigens, because the spray-drying process yielded an orally administered M hyopneumoniae vaccine that induced a good immune response. (Am J Vet Res 2002; 63:1118–1123)

Full access
in American Journal of Veterinary Research
in Journal of the American Veterinary Medical Association

Summary

Plasma catecholamine concentrations in response to onychectomy were examined in 27 cats receiving different anesthetic regimens. Each cat was anesthetized with a dissociative-tranquilizer combination, and onychectomy was performed on 1 forefoot. One week later, each cat was anesthetized with the same dissociative-tranquilizer combination plus either butorphanol or oxymorphone, and onychectomy was performed on the other forefoot. Four treatment groups were studied: tiletamine-zolazepam and tiletamine-zolazepam-butorphanol combinations were administered to group-1 cats, ketamine-acepromazine and ketamine-acepromazine-butorphanol combinations were administered to group-2 cats, tiletamine-zolazepam and tiletamine-zolazepam-oxymorphone combinations were administered to group-3 cats, and ketamine-acepromazine and ketamine-acepromazine-oxymorphone combinations were administered to group-4 cats. All drug combinations were administered im. Central venous blood samples were drawn for catecholamine analysis after injection of drug(s), after onychectomy, and 1, 2, and 4 hours after injection. Tiletamine-zolazepam alone or tiletamine-zolazepam-butorphanol prevented epinephrine release for 2 hours after injection of drug(s). Norepinephrine concentration increased significantly (P < 0.05) from baseline after onychectomy for tiletamine-zolazepam-butorphanol and at 4 hours for tiletamine-zolazepam and tiletamine-zolazepam-butorphanol. After onychectomy, there was no difference in epinephrine values between tiletamine-zolazepam and tiletamine-zolazepam-oxymorphone. Ketamine-acepromazine prevented increases in norepinephrine and epinephrine concentrations for up to 2 hours after surgery. Addition of butorphanol to ketamine-acepromazine decreased norepinephrine values immediately after onychectomy. Addition of oxymorphone to ketamine-acepromazine resulted in lower epinephrine values 4 hours after surgery.

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in American Journal of Veterinary Research

SUMMARY

Six healthy Holstein calves were anesthetized with isoflurane in O2 and instrumented for hemodynamic studies. A saphenous artery was catheterized for measurement of blood pressure and withdrawal of blood for determination of the partial pressure of carbon dioxide (PaCO2 ), oxygen (PaO2 ), and arterial pH (pHa). Respiration was controlled throughout the study. The ecg and eeg were monitored continuously. A thermodilution catheter was passed via the right jugular vein into the pulmonary artery for determination of cardiac output and measurement of central venous pressure, pulmonary arterial pressure, and pulmonary capillary wedge pressure. Baseline values (time 0) were recorded following recovery from isoflurane. Tiletamine-zolazepam (4 mg/kg)-xylazine (0.1 mg/kg) were administered iv immediately after recording baseline values. Values were again recorded at 5, 10, 20, 30, 40, 50, and 60 minutes after injection. Changes in left ventricular stroke work index, Paco2 , and pHa were insignificant. Arterial blood pressure and systemic vascular resistance increased above baseline at 5 minutes and then gradually decreased below baseline at 40 minutes, demonstrating a biphasic response. Values for pulmonary capillary wedge pressure, pulmonary arterial pressure, central venous pressure, and Pao2 were increased above baseline from 5 to 60 minutes. Stroke volume, stroke index, and right ventricular stroke work index were increased from 20 or 30 minutes to 60 minutes. Pulmonary vascular resistance increased at 10 minutes, returned to baseline at 20 minutes, and was increased again at 60 minutes. Heart rate, cardiac output, cardiac index, and rate pressure product were decreased at 5 minutes, and with the exception of cardiac output, remained so for 60 minutes. Cardiac output returned to the baseline value at 30 minutes. All calves recovered without complications. We concluded that tiletamine-zolazepam (4 mg/kg iv)-xylazine (0.1 mg/kg iv) is a safe and useful anesthetic regimen for use in calves.

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in American Journal of Veterinary Research

Objective—

To compare a prescrotal castration technique with the conventional bilateral scrotal incision technique for castration of llamas.

Design—

Prospective randomized controlled trial.

Animals—

10 clinically normal, sexually intact male llamas.

Procedure—

Five llamas were castrated by use of a 5-cm skin incision located 2 to 3 cm lateral to the ventral midline and approximately 15 cm cranial to the scrotum, which was closed with absorbable suture material to allow primary healing. Five other llamas were castrated via a more conventional technique, with a 5-cm scrotal incision positioned directly over each testis, which was allowed to heal by second intention.

Results—

The prescrotal technique required significantly more time to complete; however, no additional anesthesia was required to complete the longer procedure. Llamas castrated with the prescrotal technique required less aftercare and had less incisional pain when the area was palpated.

Clinical Implications—

Both techniques are safe and effective. Some clients, however, find the prescrotal technique more aesthetically acceptable. The prescrotal technique may be more clinically important where fly control is difficult. U Am Vet Med Assoc 1996:208:261-262)

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in Journal of the American Veterinary Medical Association

Abstract

Objectives

To use lipopolysaccharide (LPS) to create synovitis in the midcarpal joint of ponies, and to assess the morphologic, histochemical, and immunohistochemical effects of synovitis on articular cartilage of the third carpal bone.

Animals

2- to 3-year-old ponies, 6 control (group 1) and 6 treated (group 2).

Procedure

Synovitis was induced in 1 midcarpal joint of group-2 ponies by intra-articular injections of LPS (0.02 μg/kg of body weight), morphine (0.1 mg/kg), and saline solution (group 2a) and morphine and saline solution alone in the contralateral midcarpal joint (group 2b). Articular cartilage sections and attached synovial membrane from the third carpal bones were examined by immunohistochemical distribution of interleukin 1β, tumor necrosis factor (TNF)-α, TNF receptors (P55, P75) and 3-B-3(–) epitopes, and by localization of proteoglycans (metachromatic staining). Proteoglycan extracts were assessed by metachromatic staining or western blotting and immunohistochemical staining, using anti-3-B-3 antibodies.

Results

Enhanced immunoreactivity for the cytokines and receptors was found in inflamed synovial membrane and noncalcified cartilage (group 2a more than 2b). Metachromasia of the noncalcified cartilage was greater in group-1 than in group-2a and group-2b specimens. In group 2a, chondrocyte hypertrophy and enhanced immunoreactivity for 3-B-3(–) epitope in areas of increased cytokine immunoreactivity suggested possible phenotypic change of the chondrocytes in response to synovitis. Immunohistochemical analysis by western blotting of proteoglycan extracts indicated strong 3-B-3(–) epitope immunolocalization in group-2a, weaker staining in group-2b, and barely detectable stain in group-1 specimens, which correlated with in situ immunolocalization.

Conclusions

Intra-articular administration of LPS may be used to induce a synovial environment conducive to increased immunoreactivity of interleukin 1β, TNF-α, and its receptors in equine synovial membrane and articular cartilage. These cytokines may be involved in the early phenotypic change of chondrocytes that is believed to occur in osteoarthritis and is characterized in this study by enhanced 3-B-3(–) epitope immunoreactivity and chondrocyte hypertrophy. (Am J Vet Res 1996;57:1080–1093)

Free access
in American Journal of Veterinary Research