266 BRITISH VETERINARY JOURNAL, 148, 3 lems in making a decision . They stated that in the liver from pigs treated `according to good practice in the use of veterinary drugs', quinoxaline-2-carboxylic acid is the only metabolite that can currently be identi- fied, but there are unidentified residues . Because of the genotoxic and carcinogenic nature of carbadox and some of its metab- olites, the committee was not able to estab- lish an ADI (acceptable daily intake) . How- ever, the committee then went on to conclude that residues resulting from the use of carbadox in pigs were acceptable, provided that the recommended MRLs were not exceeded . The definition of what are suitable MRLs (maximum residue limits) is not given, and since this review may be used in countries with perhaps different MRIs, which MRLs did the committee have in mind? For Olaquindox, the committee was unable to establish an ADI but concluded that residues resulting from the use of Ola- quindox in food producing animals under conditions of good practice in the use of vet- erinary drugs were temporarily acceptable . Further data are required by 1993 . Again no definite details are given of what represents good practice . Overall there is a lot of information-well indexed-that is not otherwise available, with definite decisions and recommen- dations in most cases on acceptable exposure levels for residues of the appropri- ate compounds . In most cases the pharma- cokinetics and metabolism of the com- pounds are reviewed and discussed, and this information could certainly be of interest to research workers . Joue A . ;JAMrs Coronaviruses and their Diseases . Advances in Experimental Medicine and Biology, Volume 276 . Edited by D. Cavanagh & T . D . K. Brown . New York and London : Plenum Press . 1990. 676 pp . US$155 .40 Coronaviruses are responsible for several important veterinary diseases including infectious bronchitis in chickens (IBV), transmissible gastroenteritis in pigs (TGEV) and infectious peritonitis in cats (FIPV) . These viruses, and mouse hepatitis virus (MHV) also serve as excellent models with which to study RNA replication, recombina- tion and translation . In addition, MHV, which causes subacute demyelination, pro- vides a means to study mechanisms of neurological damage . This volume contains the proceedings from the 4th International Symposium on Coronaviruses held at Cain- bridge in July 1989 . The book therefore pin- points the foci of current scientific research into this unusual group of viruses, and as such will mainly be of interest to specialists rather than to general readers (especially given the cost of the volume) . Each of the individual structural proteins and the poly- merase contributes a chapter, whilst other topics covered include transcription, vari- ation and evolution, and B- and T-cell epi- topes. Most of the 13 chapters start with a short paper giving the background to the subject, which should prove to be especially useful to the non-specialist . These are then followed by series of research papers which as in any multi-author volume are of vari- able quality, although the overall standard is high. Coronavirus research has made rapid progress recently, as these papers illustrate well . The recent findings that equine arter- itis virus (previously classified as a togavirus) and Berne virus, a torovirus, share many fea- tures with the coronaviruses, has expanded the range of viruses to which the findings reported here are relevant . The recent impetus in this area looks likely to he continued . M . BiNtis The Veterinary Formulary . Handbook of Medicines used in Veterinary Practice Edited by Yolande Debuf London : The Pharmaceutical Press . 1991 . 448 pp. £37.50 (hard) I began to use this book as it was intended-'as a rapid reference'-and quickly found it to be absolutely invaluable . The classified notes on drugs and prep- arations are encyclopaedic and have let me down on very few occasions, even when dealing with human products used in veter- inary medicine . I did catch it out when look- ing for fluoroquinolone antimicrobials and for tilmicosin . However, since these were not licensed or marketed for animals at the time of publication, the editor is forgiven . The layout of the classified section is excellent and is the only really user friendly guide to chemotherapeutic products for vet-