Lyra Halprin, UC Sustainable Ag Research & Educ Program (at UC Davis)
> Date: Sat, 26 Feb 1994 07:31:40 -0800
> From: Charles Benbrook <email@example.com>
> To: firstname.lastname@example.org
> Cc: email@example.com, firstname.lastname@example.org
> 2/26/94 Sanet -- From: Chuck Benbrook Re: Corrections/Some More
> Data on BST
> Thanks to all the people who contacted me separately and
> online to correct mistakes in my earlier BST postings. I
> apologize for not doing more thorough research, but this is just a
> "recreational past-time" for me, and my real work leaves little
> time for recreation.
> I am passing along a message received from Michael Hansen,
> providing more accurate/thorough data on mastitis incidence. The
> point Michael clarifies is obviously an important one -- the
> increase in mastitis across a herd is expected to be in the range
> of 15%, while the RATE of incidence among treated cows, in
> contrast to untreated cows in the same herd, is in the 80% to 100%
> range (i.e. the relative risk nearly doubles).
> Michael raises some serious questions from one of Dr.
> Bauman's trials. Perhaps someone from Cornell could clarify what
> the data actually showed re rates in that trial.
> Some people asked for how to contact Lara Wiggert. Her new
> e-mail address is email@example.com
> BST is a big risk for the dairy industry, and the country.
> Its become a precedent setting "battle" over the factors/values
> that support regulatory decision-making. FDA concludes the drug
> is "safe" and "effective". Inherent is this decision are a set of
> "decision-rules" that are grounded in values -- weights given to
> different factors, if you will. Those critical of the decision
> cite two major factors -- different interpretation of the science
> base; different values, or weights given to a modest economic gain
> to producers/consumers+(possibly) significant gains to a few
> companies, versus the costs to producers/society of increased
> mastitis and other health problems which everyone acknowledges
> will happen when you use a hormone to push a animal to higher
> levels of performance, but which some people view as acceptable
> since the incidence of such health problems apparently falls
> within the range of incidence, from other factors. The logic
> underlying this decision-rule would support interesting decisions,
> for example, in attempts to reduce crime through gun-control, or
> deal with AIDS.
> If anyone has a FEW relevant references on the economics of
> mastitis, in the nature of review articles, please send a
> >From conpolinst, Michael Hansen Date: Fri, 25 Feb 1994 16:45:34
> -0800 From: Consumer Policy Institute/Consumers Union <conpolinst>
> Message-Id: <199402260045.QAA09211@igc.apc.org> To: cbenbrook
> Subject: rbGH info on SANET
> Got your message of 2/24. . .perhaps I should give you a
> bunch of materials on rbGH, as some of your info is misleading.
> In particular, the notion that rbgh only increases mastitis by
> 15%. This is not true!!!
> If you look at the FDA FOI summary, you'll see that the
> relative risk of clinical mastitis in rbgh-treated cows compared
> to controls during the treatment period is 1.79 overall. That
> means that there is a 79% increase in the rate of clinical
> mastitis during the treatment period. Furthermore, if we look at
> first calf heifers (i.e. cows going through their first
> lactation), the relative risk is 1.97, or a 97% increase!!! In
> addition, if we look at the data on relative risk of cases of
> subclinical mastitis, the number is 1.81, an 81% increase!! I
> think that what FDA is referring to as only a 15% increase in
> clinical mastitis might be if you lumped the data from the entire
> lactational cycle (i.e. if you include the first 9 weeks of data).
> This is not good science. To compare the effect of bGH on
> mastitis, one should only look at data from the treatment period.
> If you wanted to look at the entire lactational cycle, you should
> have data on cows treated for the entire lactational cycle. I've
> never seen any such data, but would be willing to bet that the
> increase in clinical mastitis would be higher than 100% if it were
> given during the entire lactational cycle.
> Further, you should know that the data FDA used is a very
> selective rendering of all the studies. For example, they didn't
> include the Vermont Jersey study which demonstrated a four-fold
> increase in the number of cows treated for clinical mastitis and a
> seven-fold increase in the number of cases of clinical mastitis.
> This study is a pivotal study, but it is only pivotal for
> injection site syndrome. Further, there has been much suppression
> on any adverse health effects. A big example is the Cornell
> trials (which involved 84 animals--42 controls and 42 treated).
> When Bauman et al. published the results in the J. of Dairy
> Science, they said that they observed no catastrophic adverse
> health effects. They also made a point of saying that to detect
> "subtle" differences in effects on cow health requires larger
> sample sizes and that they would lump the data from the Cornell
> trials with other data so that the sample sizes would be larger.
> It turns out, from looking at info in the FDA FOI summary and from
> slides from the VMAC (Vet. Med. Advisory Cmtee) meeting on March
> 31, that the real data on clinical mastitis from Cornell is pretty
> bad: cases of clinical mastitis went from 4 out of 42 in controls
> to 14 out of 42 in rbGH-treated animal!! I think that a 3.5-fold
> difference is more than a "subtle" health effect. I mean, 33% of
> all rbGH-treated animals getting mastitis is pretty significant
> and should constitute a catastrophic increase.
UC Sustainable Agriculture Research & Education Program
Davis, CA 95616