Tylosin tartrate - drug guide

BUGLADY 2006-03-29 15:59:15

"Sandy Christmus, DVM" wrote in message
news:2mnWf.1788$IG.784@dukeread01...

>As with most livestock antibiotics, it is available without a veterinary

prescription. On the down side, the >injudicious use of livestock
antibiotics may be part of the reason the world is

> seeing more resistant microbes overall.

.......Amen! The issue of bird flu is nothing compared to having only one
antibiotic left to treat bacterial infections.
RESISTANCE ISSUES
Microb Drug Resist. 2005 Winter;11(4):395-403.
Presence and mechanism of antimicrobial resistance among enterococci from
cats and dogs.
Leener ED, Decostere A, De Graef EM, Moyaert H, Haesebrouck F.
Department of Pathology, Bacteriology and Poultry Diseases, Faculty of
Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke,
Belgium. ellen.deleener@UGent.be
The presence and mechanism of acquired resistance to erythromycin, tylosin,
lincomycin, quinupristin/dalfopristin, tetracycline, chloramphenicol,
gentamicin, kanamycin, and vancomycin were determined in 97 and 104
enterococci isolated from rectal swabs of cats and dogs, respectively.
Eleven feline and three canine enterococcal isolates contained the
aac(6')-Ie-aph(2'')-Ia gene encoding high-level resistance to gentamicin, an
antibiotic often used for treating enterococcal infections in humans. The
combination of erm(B) and vat(E) genes encoding resistance to streptogramins
was detected in one canine quinupristin/dalfopristin-resistant Enterococcus
faecium isolate. Four quinupristin/dalfopristin-resistant enterococci only
contained the erm(B) gene. Cross resistance against macrolides and
lincosamides (30%) and resistance against tetracyclines (55%) was found to
be widely distributed among enterococci from pets. In all of the feline and
in 93% of the canine macrolide and lincosamide-resistant isolates, this
resistance was encoded by the erm(B) gene. tet(M) was the most prevalent
tetracycline resistance gene. It was detected in 91% of the feline and 86%
of the canine tetracycline- resistant enterococci. A high occurrence of the
Tn916/Tn1545 transposon family was found among these tet(M)-positive
isolates. Enterococci from pet animals with resistance against vancomycin
were not found. This study shows that enterococci from the intestinal
microbiota of cats and dogs may act as a reservoir of resistance genes for
animal or human pathogens.
PMID: 16359201 [PubMed - in process]

.......Turns out a certain percentage goes through a dog's system unchanged
and is voided in the urine, exposing the bacteria in the yard to a selection
process. Recently they've found that innocuous bacteria can transfer
resistance to pathogenic bacteria. And I'm sure it's a subclinical dose,
which is another whole issue WRT bacterial resistance. And then there's
cross resistance with erythromycin
http://lib.bioinfo.pl/meid:17307
Competitive exclusion of a glycopeptide-resistant Enterococcus faecium in
the presence of vancomycin but not equivalent concentrations of tylosin or
gentamicin.
T L Poole, K J Genovese, T R Callaway, K M Bischoff, C J Donskey, D J Nisbet
The effect of subtherapeutic concentrations of antibiotics (10.0 and 40.0
microg/mL of vancomycin, gentamicin, and tylosin) on the efficacy of a mixed
anaerobe culture of chicken microflora (CCF) was studied in a
continuous-flow fermentation system. Efficacy of CCF posttreatment was
assessed by challenge with glycopeptide-resistant Enterococcus faecium (GRE)
at 6.0 log10 cfu/mL. Bacterial enumeration of endogenous CCF isolates,
volatile fatty acid (VFA) analysis, and challenge with GRE indicated that
CCF efficacy was affected by all antibiotic treatments. Although CCF treated
with 10.0 microg/mL of vancomycin eliminated GRE13 at a rate of 0.61 log10
cfu/ mL per day, it was unable to eliminate E. coli, a gram-negative
challenge organism. All other antibiotic treatments allowed GRE persistence
at approximately 2.0 to 6.5 log10 cfu/mL. All antibiotic-treated cultures
had decreased concentrations of acetic and propionic acids. Our data suggest
that low concentrations of antimicrobials may adversely affect the microbial
ecology of gut microflora with respect to its ability to exclude exogenous
bacteria. Moreover, gentamicin had an adverse effect on the inhibitory
stringency of CCF even though it showed little anti-anaerobic activity
against CCF strict anaerobes in pure culture. Verification of the results in
live animals will be necessary to determine if antimicrobial treatment could
compromise the effectiveness of normal microflora to serve as a natural host
defense against infection.
Poult Sci. 2004 Jul ;83:1099-105

More at same url above:
In vitro Susceptibility and a New Point Mutation Associated with
Tylosin-Resistance in Japanese Canine Intestinal Spirochetes.
Nuvee Prapasarakul, Kozo Ochi, Yoshikazu Adachi
The in vitro suscetibilities of six commonly used antimicrobial agents
against 29 isolates of intestinal spirochetes isolated from dogs in Japan
were examined by the agar dilution technique. In addition, the genetic basis
of tylosin resistance in in vitro selected resistant mutants of two
reference strains and three tylosin-susceptible field isolates obtained by
three successive subcultures on blood agar containing 1 microg/ml of tylosin
was investigated. Carbadox was the most active (MIC: < 0.00625) of all the
antimicrobial agents. Although all the isolates were susceptible to tylosin,
some were resistant to erythromycin. Tiamulin, lincomycin and dimetridazole
were also very active against the isolates. All the resistant isolates did
not harbor any plasmids. In vitro selected tylosin-resistant mutants of
previously tylosin-susceptible isolates showed a new mutation in which their
adenine at the base position equivalent to 2,062 of 23S rDNA of Escherichia
coli has been replaced by cytosine. These findings may both provide guidance
towards the proper choice of antimicrobial agents for the treatment of
canine intestinal spirochetosis, and add to the understanding of the genetic
basis of tylosin resistance.
J Vet Med Sci. 2003 Dec ;65:1275-80

Multiple antibiotic resistance gene transfer from animal to human
enterococci in the digestive tract of gnotobiotic mice.
C Moubareck, N Bourgeois, P Courvalin, F Doucet-Populaire
It has been proposed that food animals represent the source of glycopeptide
resistance genes present in enterococci from humans. We demonstrated the
transfer of vanA and of other resistance genes from porcine to human
Enterococcus faecium at high frequency in the digestive tract of gnotobiotic
mice. Tylosin in the drinking water favored colonization by transconjugants.
Antimicrob Agents Chemother. 2003 Sep ;47:2993-6

...Lots more good stuff at above site including this: Tylosin-resistant
bacteria cultivated from agricultural soil.
Leslie J Onan, Timothy M LaPara

.............I am also curious how many of these dogs end up with chronic
GI problems down the line. Might be a question to ask a client who has a GI
upset dog with white fur and no tear stains! What do vets tell people who
want to address this issue?

I can't tell you the specific legalities of the general public using
livestock antibiotics on domestic

> animals. I'd guess most state's laws say you can treat your own pet
> with whatever drug you want, as long as it's not cruelty.

....yeah, nothing to stop me from going to a farm store and getting
antibiotics for my dog/cat or myself. Selling it without a vet license for
specific use in a cat/dog, is a different issue and one I intend to pursue.

>I would think the law states it's illegal to sell an antibiotic that's

licensed for

> livestock use to domestic animals over the counter.

.......That's what I thought. The label is the law. And since it's not
labeled for dogs or cats it ought to be illegal to sell it as such. There
ought to at least be all the standard things on the label that there are on
a bottle of antibiotics such as dose and expiration date. Wading through
the FDA site, however, is proving to be a PITA! I'm sure there are also
state laws WRT antibiotic use, for example certainly CA law is liable to be
different. ;-)

If it were legal,

> I'm sure there would be products on the market using numerous
> antibiotics labeled for livestock to "improve" your dog's or cat's life.

......Well, unfortunately that's what's happening. Turns out the tear stain
site is the tip of the iceburg:
http://www.calvetsupply.com/index.asp?PageAction=VIEWPROD&ProdID=18
http://www.calvetsupply.com/index.asp?PageAction=COMPANY
*We also have a wide variety of human grade antibiotics, none of which
require a prescription !*

Angel's Glow - another tear stain product, which doesn't even tell you that
an Tylosin is an antibiotic:
http://www.pamperedpetboutique.net/grooming.html

Other info on Tylan:
http://www.inchem.org/documents/jecfa/jecmono/v29je08.htm
http://www.emea.eu.int/pdfs/vet/mrls/020597en.pdf

Thanks for your reply. Appreciate it. Sorry to go on and on. I was
alarmed before, now I'm just downright mad......

buglady
take out the dog before replying