MGA MILLED IN FEED: PRODUCT INFORMATION
Mazuri ADF-16 Herbivore pellet with MGA
provides an alternative contraceptive method particularly for ungulates housed
and fed in mixed species/mixed sex herds.
Two MGA concentrations are offered to allow for delivery of the
appropriate MGA dose. This product is
considered suitable for bovids, giraffes, cervids, camelids and hippos, but
is not effective in suids or equids.
The product
is available only as part of an experimental trial coordinated by the
The FDA requires all medicated diets
be manufactured under an INAD (New Animal Drugs for Investigational Use, 21 CFR
511.1(a)). Purina Mills LLC was granted
permission to manufacture MGA-treated herbivore pellet for use in this project
under their existing INAD on file with the FDA.
Therefore, all participating institutions must obtain the experimental
MGA feed through the
SAFETY OF MGA FEED TO HUMANS
When used as directed, this product
poses no health risk to humans. Domestic
cattle are 240 times more sensitive to MGA than are humans, i.e., a human would
have to ingest a dose 240 times higher than that ingested by cattle to have the
same effect. The doses being recommended
for exotic ungulates are within the range used for cattle. Purina Mills, Inc. believes it is not
hazardous materials according to the OSHA Hazard Communications Standard, 29
CFR 1910.1200 or the EPA Community Right-to-Know regulations. Questions about the Purina Mills MSDS program
should be directed to Mr. Paul Luther at 314-768-4630.
SAFETY OF MGA FEED TO TREATED ANIMALS
MGA has been fed to domestic cattle
for decades without untoward effects, which suggests that it should be
generally safe for ruminants. However,
exotic species have not been treated for more than 5 years, so possible long
term effects are not known. Also,
species differences may apply.
RECOMMENDED DOSES OF MGA FEED
The two concentrations are:
Mazuri ADF-16 0.1MA (5ZA4)
containing 0.1 mg MGA/lb, and Mazuri ADF-16 0.5MA
(5ZA5) containing 0.5 mg MGA/lb. Either concentration alone or in combination
may be used to achieve the recommended daily MGA dose/animal for your
individual feeding program. The following daily MGA doses are recommended:
0.5 mg
MGA/day/animal for species with body size smaller than an adult, female banteng (about 800 lb).
1.0 mg
MGA/day/animal - for species with body size similar to or larger than an adult,
female banteng.
2.0 mg MGA/day/animal - for hippos and
giraffe (some giraffe have needed as much as 3.0 mg/day to suppress estrous
behavior).
NOTE:
The maximum safe dose is considered to be more than 3 times that
recommended here.
The amount of pellet and choice of
concentration depends on the species, the body size and on your particular
feeding program. The MGA herbivore
pellet is intended to replace the regular herbivore pellet in your current
diets. The pellet should still be fed in
conjunction with hay, in an amount that meets the recommended minimum daily MGA
dose while still meeting the nutritional needs of the animals.
In general, ruminant herbivores have a
daily diet intake of 1.5 – 4.0% body mass (BM), with larger species consuming
food at a smaller percentage of BM than medium or small species. The amount of herbivore pellet to feed is
based largely on the quality of hay fed, and the pellet is intended to correct
the nutrient imbalances or deficits that might occur on a diet of only
hay. Regular analysis of the nutrient
content of your hay is highly recommended.
It may be necessary to make adjustments in your current feeding regimens
in order to deliver the appropriate dose of MGA via the new herbivore
products. Current recommendations from
zoo nutritionists suggest that medium to large size ruminant herbivores should
receive 30-40% of the diet (by weight, as fed basis) as a nutritionally
complete herbivore pellet and 60-70% of the diet (by weight, as fed basis) as
hay. The type of hay(s) used (i.e.,
legume or grass hay, species of hay) in the diet is dependent on the nutrient
content of the hay, the species being fed and hay types available in your area.
If you would like assistance in
determining an appropriate feeding plan, please contact
REPORTING REQUIRED FROM INSTITUTIONS
USING MGA FEED
All institutions using MGA feed must
submit an annual report to the AZA Wildlife
LATENCY TO EFFECT
As with implants and injections,
separation or alternative contraception should be used for 1-2 weeks.
ESTROUS CYCLES DURING CONTRACEPTIVE
TREATMENT
MGA in feed, like other synthetic
progestins, allows for contraception by blocking ovulation, causing thickening
of cervical mucus, slowing ovum transport, and/or interfering with
fertilization or implantation. However,
follicle growth may continue and sometimes be accompanied by estrogen
production sufficient to cause estrous behavior. Ovulation may occur even though pregnancy
does not ensue. Higher progestin doses
may be preferred so that estrous behavior is blocked, but may not be effective
in completely suppressing follicle growth and estradiol production.
DURATION OF EFFICACY
Duration of efficacy may not be much
more than one day, so must be administered daily.
REVERSIBILITY
Time to reversal can vary for many
reasons. The most basic measure of
reversal is when the concentration of the contraceptive compound in the body
drop below the level of efficacy.
However, it is often not possible to measure this event, so confirmation
that reversibility has been successful must depend on documentation that ovulatory cycles have resumed or diagnosis of pregnancy or
birth of young. Many factors other
than contraceptives affect ovulation and conception. These include reproductive history, age,
health, body weight (very thin or obese animals may not ovulate or conceive)
and, of course, fertility of the partner.
Circulating MGA clears very rapidly following cessation of treatment, so
ovulation and conception may occur within days, although actual latency is
usually longer and will depend on the individual.
CONTRACEPTION FOR SEASONAL BREEDERS
Treatment should begin at least one
month before the anticipated onset of the breeding season.
CONTRACEPTION DURING PREGNANCY
MGA in feed, like other synthetic
progestins, is not recommended in pregnant animals because of the possibility
of prolonged gestation, stillbirth, abortion, etc. in some species, although
the effect may depend on dose.
CONTRACEPTION DURING LACTATION
MGA in feed, like other synthetic
progestins, is considered generally safe for nursing infants.
PRE-PUBERTAL CONTRACEPTION
MGA in feed has been shown not to
affect pre-pubertal female domestic cattle.
WEIGHT GAIN
Like all synthetic progestins, MGA in
feed probably causes weight gain in all species.
CONTRACEPTION DATABASE SURVEY
Because all contraceptives used in
exotic species must be considered experimental, it is critical that records be
kept on each method used, dose, date started, date ended, presence of
opposite-sex in group, signs of estrous behavior, birth dates of any offspring
born, abortions, date of death if an individual dies during treatment, and any
other pertinent observations, especially pathology that might be related to
contraceptive use. Records must be
included annually in the
Sally Boutelle
Program Coordinator
314-646-4595; Fax:314-646-5534
Contraceptive Health Surveillance
Program
The AZAWildlife
Contraception Center (WCC) conducts pathology surveillance to identify adverse
reactions that might be associated with contraceptive products. For this surveillance, we are requesting
reproductive tracts from all male (MGA-fed males) and female mammals treated
with contraceptives as well as from non-contracepted individuals, so we can compare normal
changes with lesions arising from contraceptive use.
Instructions for Submission of Tissue
Reproductive
tracts can be fixed in buffered formalin by immersion of the entire tract for
72 hrs if a small incision is made in each uterine horn, making sure there is a
ratio of 1 part tissue to 10 part formalin.
If sending the entire tract is impractical, send a description (or
photos) of necropsy results, samples of all lesions, 2 endometrial samples (be
sure to include both caruncles and inter‑caruncular areas) and both ovaries. Submission forms can be found in the Health
Surveillance link
on our webpage. A brief summary of the
reproductive history of each animal should be included. We will send a pathology report for the
tissues you submit and will be certain to acknowledge your institution’s contribution
in any publication that includes your submission. Please
note that this is a research project and, as such, reports may not be as timely
as a standard diagnostic report. If
there is urgency in getting a reproductive diagnosis, please contact Dr. Agnew
directly.
Send tissue
and reports to:
Dr. Dalen Agnew
Attn: Histo
Research
Diagnostic Center for Population and
Animal Health
4125 Beaumont Rd.
Lansing, MI USA 48910-8104
Phone: 517-353-1683
RESEARCH OPPORTUNITIES
Fecal Sample Collection to Monitor
Ovulation
If your institution can collect feces
weekly from known individuals and wish for hormone analysis, please contact Dr.
Collection of Fecal Samples:
1. Collect sample as fresh as
possible.
2. Scoop up about a spoonful
(inexpensive plastic coffee spoons are convenient for this).
3. Place in small zip-lock bag. Do not overfill bag. Make sure it is well sealed.
4. Using permanent black marker
(Sharpie), clearly label bag with animal ID and date of collection.
5. Freeze immediately, at -70EC
if possible.
6. Ship on dry ice by overnight courier to:
Joan
E. Bauman, Ph.D.
Research
Department
7. Mark box “Frozen Specimens”. Include information in the box clearly identifying species, what assays are requested (i.e.: progesterone for cycle monitoring), and contact information for the sender.
8. Notify
Feed Consumption Study
If you are
interested in participating in a feed consumption study, please contact
TO PURCHASE MGA FEED
Before placing your first order, you must register
with the
REGISTRATION FOR PARTICIPATION IN AZA
WILDLIFE CONTRACEPTION CENTER TRIALS OF MAZURI ADF-16 HERBIVORE PELLET WITH
MELENGESTROL ACETATE (MGA) FOR CONTRACEPTION OF BOVIDS, CERVIDS, CAMELIDS,
GIRAFFES, AND HIPPOS
Contact person (responsible for
reporting): Date:
Phone/E-mail address:
Institution:
Address:
City/State/Zip:
Purina Mills
dealer/phone:
Species and Proposed Feeding Regimen:
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Species |
Number and Gender* of Animals |
ID or ISIS# |
Product Code (5ZA4, 5ZA5, etc,) |
lbs. of feed/animal/day |
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*
reported as number of males.females (i.e. 1.1 = 1 male, 1 female)
By this application, the participating institution
agrees to feed the contraceptive product only to approved species at the
recommended dosage, and also agrees to submit the Wildlife
Veterinarian Signature (required):_____________________________________________________
Mail MGA Feed Registration Form to:
Sally Boutelle
Program Coordinator