Evaluation of an ultrasonic Doppler probe for pregnancy diagnosis in cattle

SUMMARY The use of an ultrasonic Doppler probe for pregnancy diagnosis was evaluated. Data from the examination of 1115 cattle were analysed. Comparison of the probe with manual rectal palpation by an experienced clinician yielded a sensitivity of 92.8 ± 1.6% (± 95% confidence interval) and a specificity of 75.8 ± 7.4%. This level of accuracy was found to be insufficient to recommend the probe be used by farmers for the diagnosis of pregnancy.     

Effects of increasing days of exposure to prepartum transition diets on reproduction and health in dairy cows

Objective To evaluate the effect of the number of days exposure to a prepartum transition diet on reproduction and health in dairy cows. Design A prospective cohort study. Procedures We enrolled 1008 dairy cows from three herds to examine the effects on reproduction and health of increased days exposure to prepartum transition diets that included ryegrass pasture, ryegrass silage, cereal hay, grain, by-products, oilseed meals, BioChlor®, rumen modifiers, minerals and vitamins. Diets provided 9.9 MJ metabolisable energy per kg dry matter (DM), a metabolisable protein balance of 286 g/day and a dietary cation anion difference of −150 meq/kg DM. Statistical models controlled for herd, calving day, age and gestation period. Results In two of the three herds increased days exposure to prepartum transition diets increased the hazards of submission for breeding, conception and clinical mastitis, and decreased the hazard of cow removal. The odds of pregnancy by 6 and 21 weeks after the mating start date tended to increase with increasing days of exposure to prepartum transition diets. Conclusions Increasing exposure to a prepartum transition diet improved the calving to conception interval, tended to improve the odds of pregnancy and reduced the risk of culling of cattle, but increased the hazard of clinical mastitis.     

Retrospective study of 108 foals with septic osteomyelitis

Objective   To determine the clinical characteristics, short-term outcome and future athletic performance of foals with septic osteomyelitis.
Design   Retrospective clinical study of 108 Thoroughbred foals with radiographic evidence of bone infection that were presented at the Scone Veterinary Hospital between August 1995 and December 2001. Medical records were reviewed and information concerning signalment, the clinical, laboratory and radiographic findings, treatment and outcome was obtained. Racing records were obtained and evaluated for surviving foals that had reached racing age.
Results   Mean age of foals at initial evaluation was 39 days (range 1–180 days); 21 foals had multiple radiographic bone lesions (19.4%), and 76 had concurrent septic arthritis (70.4%). The most frequently affected bones were the femur, tibia and distal phalanx. In total, 87 foals were discharged from the hospital (80.6%), 79 survived long-term to reach racing age and 52 raced (65.8%). Overall, 48% (52/108) of the foals treated for osteomyelitis raced. Foals less than 30 days of age at the time of diagnosis, critically ill foals and those with multiple bones or joints affected were significantly less likely to be discharged from hospital. Multiple septic joints, but not multiple bone involvement, had an unfavourable prognosis for racing.
Conclusions   The prognosis for survival of foals with septic osteomyelitis or osteitis is favourable. Multiple bone or joint involvement is an important short-term prognostic indicator; however, the involvement of multiple joints, but not multiple infected bones, is associated with an unfavourable prognosis for racing.     

Use of enzyme-linked immunoassays for antibody to types C and D botulinum toxins for investigations of botulism in cattle

The development of specific enzyme-linked immunosorbent assays (ELISA) for antibody to types C and D Clostridium botulinum toxins for investigation of botulism in cattle is described. Partially purified type C and D toxins were used as antigens to develop these ELISAs. Specificity of the ELISAs was evaluated on sera from 333 adult beef and dairy cattle from areas with no history or evidence of botulism in animals or water birds. The test was also evaluated on sera from 41 herds that included herds vaccinated against botulism, confirmed botulism cases and herds from areas where the disease is considered endemic. The ELISAs detected the presence of antibody to botulinum toxins in samples from vaccinated cattle and both convalescent and clinically normal animals from unvaccinated herds with outbreaks of botulism. Antibody was also found in unvaccinated animals from herds in which there had been no diagnosed botulism cases in areas where botulism was considered endemic. Sera from some unvaccinated cattle with high ELISA reactivity was shown to be protective for mice in botulinum toxin neutralisation tests. The use of these tests in investigations of botulism in cattle is discussed.     

Evaluation of chemical restraint,isoflurane anesthesia and methadone or tramadol as preventive analgesia in spotted pacas (Cuniculus paca) subjected to laparoscopy

ObjectiveTo evaluate the efficacy and cardiopulmonary effects of ketamine–midazolam for chemical restraint, isoflurane anesthesia and tramadol or methadone as preventive analgesia in spotted pacas subjected to laparoscopy.Study designProspective placebo-controlled blinded trial.AnimalsA total of eight captive female Cuniculus paca weighing 9.3 ± 0.9 kg.MethodsAnimals were anesthetized on three occasions with 15 day intervals. Manually restrained animals were administered midazolam (0.5 mg kg^–1) and ketamine (25 mg kg^–1) intramuscularly. Anesthesia was induced and maintained with isoflurane 30 minutes later. Tramadol (5 mg kg^–1), methadone (0.5 mg kg^–1) or saline (0.05 mL kg^–1) were administered intramuscularly 15 minutes prior to laparoscopy. Heart rate (HR), respiratory rate, mean arterial pressure (MAP), peripheral oxygen saturation (SpO₂), end-tidal CO₂ partial pressure (Pe′CO₂), end-tidal concentration of isoflurane (Fe′Iso), pH, PaO₂, PaCO₂, bicarbonate (HCO₃^?), anion gap (AG) and base excess (BE) were monitored after chemical restraint, anesthesia induction and at different laparoscopy stages. Postoperative pain was assessed by visual analog scale (VAS) for 24 hours. Variables were compared using anova or Friedman test (p < 0.05).ResultsChemical restraint was effective in 92% of animals. Isoflurane anesthesia was effective; however, HR, MAP, pH and AG decreased, whereas Pe′CO₂, PaO₂, PaCO₂, HCO₃^? and BE increased. MAP was stable with tramadol and methadone treatments; HR, Fe′Iso and postoperative VAS decreased. VAS was lower for a longer time with methadone treatment; SpO₂ and AG decreased, whereas Pe′CO₂, PaCO₂ and HCO₃^? increased.Conclusions and clinical relevanceKetamine–midazolam provided satisfactory restraint. Isoflurane anesthesia for laparoscopy was effective but resulted in hypotension and respiratory acidosis. Tramadol and methadone reduced isoflurane requirements, provided postoperative analgesia and caused hypercapnia, with methadone causing severe respiratory depression. Thus, the anesthetic protocol is adequate for laparoscopy in Cuniculus paca; however, methadone should be avoided.     

An evaluation of calf castration by intra-testicular injection of a lactic acid solution

This experiment evaluated intra-testicular injection of a sclerosing drug, lactic acid, for castration of bulls. Its use was compared in 58 Brahman cross calves (50 to 128kg) with the general practice of open surgical castration. Chemical castration appeared to be more painful than surgical castration, though post-operative swelling and pain appeared similar for both methods. Chemical castration took 3 times longer than surgical castration (58 sec v 20 sec; P less than 0.01). Scrotal necrosis occurred in 25% of chemically-castrated calves and appeared due to drug leakage from the testes under the high pressure of injection. Healing time for chemical castrates was approximately twice that for surgical castrates. Five chemically-castrated calves (18%) retained one testis. Though all 5 were rendered sterile, each maintained androgenesis. This led to secondary male behaviour which caused management problems. Castration method did not influence post-operative growth. It is concluded that lactic acid administration is not a suitable alternative to the open surgical technique for castration of Brahman cross calves.