The effect of different combinations of local anaesthesia,sedative and non-steroidal anti-inflammatory drugs on daily growth rates of dairy calves after disbudding

AIM: To assess the effect of sedation and local anaesthesia (LA) at disbudding, and the addition of meloxicam or ketoprofen treatment, on weight gain in dairy calves following disbudding.

METHODS: Friesian-Jersey cross calves, from four dairy farms, were enrolled when 3–6 weeks old. All calves (n=271) were disbudded by veterinary personnel and randomly assigned to six groups: 136 were disbudded without sedation or LA, of which 31 received 20 mg meloxicam S/C and 75 received 150 mg ketoprofen I/M. A further 135 were disbudded with sedation (0.25 mg/kg xylazine I/M) and LA, of which 30 also received meloxicam and 75 received ketoprofen. Calves were weighed 3 days before, and 15 and 30 days after, disbudding (Day 0). Daily weight gain was analysed using mixed models and ANOVA.

RESULTS: Complete results were obtained from 263 calves. From Day ?3 to Day 15, the growth rate of calves disbudded without pain relief (0.53 (95% CI=0.47–0.60) kg/day) was less that of calves disbudded with some form of pain relief (0.65 (95% CI=0.62–0.68) kg/d; p=0.004). There was no difference between the effect of meloxicam or ketoprofen (p=1.00). An interaction between use of sedation and LA and additional non-steroidal anti-inflammatory drugs (NSAID) meant that NSAID treatment did not increase growth rates in calves disbudded with sedation and LA but did increase growth rates for calves disbudded without pain relief (p<0.05). From Day 16 to Day 30 there was no effect of NSAID treatment on growth rate, but calves receiving LA and sedation grew faster (0.74 (95% CI=0.69–0.80) kg/day) than calves disbudded without LA and sedation (0.66 (95% CI=0.61–0.71) kg/day; p=0.018). From Day ?3 to Day 30, calves disbudded with sedation and LA grew faster (0.71 (95%CI=0.64–0.77) kg/day) than calves disbudded without sedation and LA (0.60 (95% CI=0.55–0.65) kg/day; p=0.011). However, addition of NSAID to sedation and LA made no further difference to growth rates (p=0.69).

CONCLUSIONS: Dairy calves disbudded with no pain relief had slower growth rates than calves receiving pain relief. From Day 15 to 30 calves given no pain relief, or NSAID alone, grew more slowly than those receiving sedation and LA at disbudding. The addition of NSAID treatment to sedation and LA did not further increase growth rates.

CLINICAL RELEVANCE: This study adds to the evidence that pain management when disbudding is beneficial for calf productivity as well as calf welfare.     

Beta-lactam antibiotics prevent Salmonella-mediated bovine encephalopathy regardless of the β-lactam resistance status of the bacteria

This study assessed the capacity of β-lactam antibiotics to prevent salmonella-mediated encephalopathy in calves given the putative neuroprotective effects of these drugs of increasing glutamate export from the brain. Both ampicillin and ceftiofur prevented the development of encephalopathy despite resistance of the inoculated Salmonella enterica serovar Saint-Paul isolate to both drugs. A glutamate receptor antagonist also prevented this salmonella-mediated encephalopathy. Glutamate exporters were hyper-expressed in the presence of β-lactam antibiotics while a glutamate export inhibitor obviated the effects of these antibiotics, demonstrating a neuroprotective effect through glutamate export from the brain. The findings indicate that β-lactam antibiotics remain an important treatment option for this atypical form of bovine salmonellosis.     

Cerebrospinal fluid from a dog with neurologic collapse

A 3-year-old Staffordshire Terrier was presented to the Texas Veterinary Medical Center with a short progressive history of anorexia, weight loss, and weakness that had progressed to ataxia and collapse with empirical treatment. The dog was tetraparetic and obtunded. Results of a complete neurologic evaluation were consistent with severe, multifocal to diffuse disease involving the forebrain, spinal cord, and brainstem. Cerebrospinal fluid, obtained via cerebellomedullary cisternal puncture, was highly cellular and contained large atypical round cells with small numbers of nondegenerate neutrophils and large mononuclear cells. Rare eosinophils and small lymphocytes were noted. The atypical round cells were approximately 15–25 μm in diameter with a single nucleus set in a small amount of cytoplasm. The nuclei were typically round to slightly ovoid; however, occasional notched, lobulated, and reniform nuclei were observed. These cells were interpreted as malignant lymphocytes. Owing to a grave prognosis, the animal was euthanized and a necropsy was performed. No gross lesions were found in the central nervous system. Multiple sections of cerebellum, medulla, and spinal cord contained a diffuse neoplastic infiltrate that was predominantly meningeal with rare superficial neuropil invasion. The neoplastic cells were arranged in sheets, cords, and rosettes. Immunohistochemical staining for vimentin, pancytokeratin, CD3, CD79a, synaptophysin, S-100, and neuronspecific enolase was negative; glial fibrillary acidic protein (GFAP) staining was equivocal. Based on histologic findings, a diagnosis of medulloblastoma was made. This case documents the rare occurrence of a canine medulloblastoma and illustrates the difficulty in distinguishing between some embryonal brain tumors and lymphoma.     

Vehicle design and thermal comfort of poultry in transit

1. Four second‐generation artificial chickens (Glorias) simulated the sensible heat exchanges, H, of pullets and end‐of‐lay hens which they accompanied throughout commercial transit in different sites of the loads.

2. Data from two summer and two winter journeys on each of 5 naturally‐ and 2 fan‐ventilated vehicles were used to derive general equations to predict H and temperature lift for each vehicle.

3. From these, air movement, V, within the crates was calculated together with predicted H at ambient temperatures to compare the thermal comfort of the vehicles.

4. All naturally‐ventilated vehicles were over‐ventilated in motion, with mean V ranging from 0.9 to 2.4 m/s within the crate, and maximum V of 6.0 m/s resulting in negligible temperature lift above ambient. Poorly‐feathered hens were, consequently, extremely cold‐stressed in winter. When stationary, vehicles with a central passage that enabled the ‘stack effect’ to operate were thermally comfortable provided V was kept low. Designs stocked over die whole floor area of the vehicle were too hot.

5. Fan‐ventilated vehicles had a similar range of H whether stationary or in motion. The mean V of 1 to 2 m/s of bird‐warmed air maintained satisfactory thermal conditions most of the time.

6. For current designs of poultry vehicle stocked at commercial rates, V should normally be between 0.3 and 1.0 m/s; air temperature near pullets or broilers should be 10.15°C and near poorly‐feathered hens 22–28°C. Suitable ventilation rates are likely to be in the range 100 to 600 m³ per hour. It is strongly recommended that appropriate temperature monitoring systems be fitted on all vehicles.     

Continental drainage in north america during the phanerozoic from Nd isotopes

Neodymium (Nd) isotopic data show consistent patterns in the sources of sedimentary rocks in North America at a continental scale. Between 600 and 450 million years ago (Ma), ancient continental shield sources dominated. Around 450 Ma, detritus from the Caledonian-Appalachian mountains overwhelmed sediment from all older sources, and is documented over large areas of the southern, western, and northern margins of North America. This material continued to dominate the sediment supply until about 150 Ma, probably due to cannibalistic recycling of sedimentary rocks formed earlier. Around 150 Ma, the rising western Cordillera delivered new and different detritus to the sedimentary system.