Preanaesthetic use of atropine in small animals

Although it is unwise to recommend any preanaesthetic drug or regimen to be used routinely without consideration for the individual patient, the procedure being undertaken or the other drugs that will be used during the anaesthetic, of all anaesthetic-related drugs that might be under review, atropine is probably one of the least 'toxic' and least likely to cause life-threatening complications when used correctly. In most small veterinary practices there isn't the luxury of a dedicated anaesthetist available to monitor and manage each anaesthetised patient and the best form of cardiac monitor available may be an audible rate monitor. In this situation the advantages combined with the usual indications probably far outweigh the disadvantages of using atropine prophylactically. If a choice must be made, a sinus tachycardia under anaesthesia is probably preferable to a profound bradyarrhythmia. Absolute contraindications for using atropine are rare; the drug, when used alone, has low incidence of toxicity at clinically recommended doses in dogs and cats. Further, the new inhalation agents available to veterinarians (enflurane and isoflurane) do not sensitise the heart to the effect of catecholamines, so that the predominance of sympathetic tone produced when atropine is used is unlikely to precipitate dysarrthythmias during gaseous anaesthesia. Rhythm disturbances that occur under halothane anaesthesia when atropine is used, suggest there is some other cause, or agent, that is arrhythmogenic, such as an alpha 2 agonist, excessively deep level of anaesthesia, hypercapnia or hypoxaemia. Notwithstanding the above arguments, my preference, as a specialist anaesthetist, is that a drug is given only as required (not before) and that when, for example, any unusual heart rhythm occurs, all possible reasons for the occurrence (such as excessively deep anaesthesia or hypoventilation) are eliminated before other drugs like atropine or antiarrhythmics are administered.     

Use of a polymerase chain reaction assay to detect bovine herpesvirus type 2 DNA in skin lesions from cattle suspected to have pseudo-lumpy skin disease

Beef cattle from a herd in north Alabama were examined because of an outbreak of nonfatal skin disease characterized by discrete circumscribed areas of inflammation that developed on the skin from the neck to the hips. Areas of inflammation, which tended to be superficial, underwent necrosis and scabbed over. The scabs eventually dropped off leaving discrete, round, whitish, hairless lesions that were 1.2 to 2.5 cm diameter. Because clinical signs were consistent with those expected with pseudo-lumpy skin disease (PLSD) caused by bovine herpesvirus type 2 (BHV-2), samples from 16 representative animals were submitted for BHV-2 testing. All 16 animals were seropositive for BHV-2, but the virus could not be isolated from skin biopsy specimens or buffy coat samples. Results of a polymerase chain reaction assay incorporating primers designed to amplify 2 DNA sequences from BHV-2 were positive for 3 of the 10 cattle, suggesting that skin lesions in these cattle were a result of PLSD. Our findings suggest that PLSD may be more common and widespread in the United States than suggested by the frequency with which BHV-2 has been isolated from cattle with PLSD-like skin lesions.     

Forage systems for production of stocker steers in the upper south

The southern states produce large numbers of beef calves that are generally weaned and sold in autumn. Keeping calves in this region beyond weaning to graze high-quality forages through a stocker cattle phase could improve profitability. Autumn-weaned Angus crossbred steers were allocated by breeding and weight to four forage systems that began in mid-November and continued through mid-October as follows: System 1, tall fescue (Festuca arundinacea Schreb.) and Kentucky bluegrass (Poa pratensis L.)-white clover (Trifolium repens L.); System 2, tall fescue, caucasian bluestem (Bothriochloa caucasica [Trin.] C. E. Hubbard) and tall fescue-red clover (Trifolium pratense L.); System 3, orchardgrass-alfalfa and bluegrass-white clover; and System 4, rye (Secale cereale L.), soybeans (Glycine max)-foxtail millet (Setaria italica), and bluegrass-white clover. All steers were supplemented with hay or silage previously cut from their respective systems when forage for grazing was limited. System 2 which used stockpiled tall fescue for winter grazing and caucasian bluestem for summer forage plus fescuered clover for hay and grazing in a three-paddock system, resulted in greater (P < .01) gain per hectare and per steer, more grazing days, and reduced stored forage requirements and produced more surplus feed than the other systems tested. Gains per hectare for Systems 1 through 4 were 454, 554, 472, and 487 kg (SE = 18), respectively. Harvested forage from Systems 1, 2, and 3 met needs for stored forages but System 4 required additional "purchased" hay. Stored forage was fed for 61, 38, 112, or 104 d for Systems 1 through 4, respectively. Within the physio-climatic region of this experiment, a simple three-paddock system based on cool- and warm-season perennial forages could improve beef production per unit of land area while reducing inputs of labor and equipment.     

道塞特、萨福克与阿勒泰羊5月龄杂交公羔肉品质分析

选取5月龄萨福克×阿勒泰(SAF1、SAF2)、道塞特×阿勒泰(DAF1、DAF2)杂交一、二代羔羊与同龄阿勒泰羊(ALT)各3只,对肉品质进行分析。结果表明:5月龄杂交羔羊肉品质得到明显改善,特别是蛋白质、脂肪和氨基酸含量变化尤为明显,且杂交二代优于杂交一代,杂交组合SA优于DA。