Animal Residue Data Sheet - Mepiquat

Mepiquat is registered in Australia for use on cotton. Details of the registered use patterns can be found on the approved labels of registered products containing mepiquat as the active constituent. This Animal Residue Data Sheet provides information on the possible residues in feed commodities obtained from crops treated with mepiquat. It also provides information on the anticipated maximum dietary exposure of animals fed treated commodities, which should not result in the violation of animal MRLs.

Current MRLs

The current Australian MRLs for mepiquat in food and animal feed commodities, as listed in Table 1 and Table 4 of the MRL Standard (as at August 2002) are shown below. The residue definition of mepiquat is the parent compound per se.

Code Food Current MRL, mg/kg
Food Commodities
SO0691 Cotton seed 1
OR0691 Cotton seed oil, edible 0.2
Animal Commodities
MO0105 Edible offal (mammalian) 0.1
  Meat [mammalian] 0.1
ML0106 Milks 0.05
PE0112 Eggs 0.05
PO0111 Poultry, Edible offal of 0.1
PM0110 Poultry meat 0.1
Animal Feed Commodities
Cotton seed meal and hulls 2

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Summary of Maximum Feeding Levels and Livestock Dietary Intakes

The Maximum Feeding Level (MFL, the feeding level at which the MRLs are based), the equivalent Daily Dietary Intake For Livestock (DDIL) and the equivalent daily intake of mepiquat are summarised below.

Species MFL,
ppm in diet
Equivalent DDIL, mg/kg bw Equivalent intake of mepiquat,
mg/animal/day
Cattlea 6.5 0.20 100
Sheepb 6.5 0.20 12
Pigc 6.5 0.20 12
Poultryd 5 0.43 0.70
a Based on 473 - 502 kg (av 483 kg) lactating cows consuming ~14 kg/day of feed and mepiquat chloride at a dose level equivalent to 13 ppm in the feed.
b Based on the available data for lactating cows and a bw of 60 kg
c Based on the available data for lactating cows and a bw of 60 kg
d Based on 1.4 — 2.1 kg (av 1.6 kg) birds consuming ~150 g/day of feed and mepiquat chloride at a dose level equivalent to 5 ppm in the feed.

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Detailed Information

All Feed Commodities

Feed commodities that may contain residues of mepiquat are listed in the table below. The theoretical maximum proportion of the diet that the commodity can comprise, when residues are present at the MRL, without the significant risk of animal commodity MRLs being violated is also given. For instance, cotton seed could be fed to cattle at 100% of the diet with minimum risk of cattle commodity MRLs being violated. It should be noted that the feeding levels assumed by the APVMA when setting animal commodity MRLs are theoretical values, and they should not be taken as recommendations of appropriate rations for livestock.

Commoditya Assumed Maximum proportion of diet (%)b Feed intake (kg/animal/day)c STMR / STMR-P
(mg/kg)d
Maximum intake of mepiquat from commodity (mg/animal/day)e Theoretical maximum proportion of diet (%)f
Cattle (Based on a 500 kg animal consuming 20 kg DM/day)
Cotton seed 30 6 0.2 (STMR) 1.2 100
Cotton seed meal and hulls 30 6 0.3 (STMR-P) 1.8 100
Sheep (Based on a 60 kg animal consuming 2.5 kg DM/day)
Cotton seed 30 0.75 0.2 (STMR) 0.15 100
Cotton seed meal and hulls 20 0.5 0.3 (STMR-P) 0.15 100
Pigs (Based on a 60 kg animal consuming 2.5 kg DM/day)
Cotton seed 30 0.75 0.2 (STMR) 0.15 100
Cotton seed meal and hulls 20 0.5 0.3 (STMR-P) 0.15 100
Poultry (Based on a 2 kg animal consuming 150 g DM/day)
Cotton seed 30 0.045 0.2 (STMR) 0.009 100
Cotton seed meal and hulls 20 0.03 0.3 (STMR-P) 0.009 100
aThe feed commodities that may contain residues of mepiquat, and may form more than 20% of an animals diet.
b The maximum % of the diet that the commodity is assumed to comprise for the purposes of setting MRLs, based on Stockfeed Information Document 1.
c The equivalent amount of feed for an animal of designated weight and feed intake that is assumed for the purposes of setting MRLs.
d The STMR / STMR-P for each feed commodity (correction for dry weight basis where required).
e The maximum intake of mepiquat when the commodity is fed at the maximum assumed level (Column 1) in the absence of other sources of mepiquat.
f The maximum % of the diet at which the commodity could theoretically be fed without significant risk of exceeding animal commodity MRLs. It is assumed that the residue in the feed commodity is present at the STMR (or dry weight equivalent) and other dietary sources of mepiquat are absent.

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Abbreviations and Definitions

DM: Dry matter. The feed consumption for livestock and the residue levels in feed commodities are expressed on a dry matter basis.

DDIL: Daily Dietary Intake for Livestock. The level of dietary exposure for a specified chemical in a specified species that should not result in exceedance of the relevant animal commodity MRLs. Expressed in mg chemical/kg bodyweight.

MFL: Maximum Feeding Level. The level of dietary exposure for a specified chemical in a specified species that should not result in exceedance of the relevant animal commodity MRLs. Expressed in terms of ppm in the feed.

MRL: The concentration of a chemical residue, in units of mg/kg, that is legally permitted in or on a food or food commodity.

ppm in the feed: Parts per million in the feed. An alternate way of expressing the level of dietary exposure for a chemical. The level of chemical intake is calculated as though it were present uniformly in the total feed intake. The ppm in the feed is calculated using the following formula: DDIL (mg chemical/kg bw) _ body weight (kg) ¸ daily feed intake

STMR-P: Supervised Trial Median Residue of the processed commodity. The highest residue that livestock are likely to be exposed to in practice when fed processed commodities over a prolonged period. This is derived from the STMR of the whole commodity multiplied by the processing factor.

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Attachment 1: Anticipated Maximum Dietary Exposure

The following calculations outline the theoretical diet used to calculate the maximum anticipated dietary exposure, maximum feeding level (MFL) and the daily dietary intake for livestock (DDIL) for cattle, sheep, pigs and poultry.

Cattle

Feed group Feed commodity % in the diet Feed intake, kg/animal/daya STMR, mg/kg % DMb Intake of mepiquat, mg/animal/dayc
Plant protein meals
[30% maximum]
Cotton meal and hulls 30 6 0.3 - 1.8
Total   30 6     1.8
aBased on assumed feed consumption of 20 kg dry matter/day
bEstimate of percentage dry matter. Applied to MRLs expressed on a fresh weight basis
cBased on assumed bodyweight of 500 kg
Maximum anticipated dietary exposure: 1.8 mg/animal/day
Equivalent to: 0.0036 mg/kg bw
Equivalent to: 0.09 ppm in the diet
MFL (Based on the available lactating
cow feeding data):
6.5 ppm in the diet
Equivalent DDIL: 0.2 mg/kg bw

Sheep

Feed group Feed commodity % in the diet Feed intake, kg/animal/daya STMR, mg/kg % DMb Intake of mepiquat, mg/animal/dayc
Oilseeds
[30% maximum]
Cotton seed 30 0.75 0.2 - 0.15
Total   30 0.75     0.15
aBased on assumed feed consumption of 2.5 kg dry matter/day
bEstimate of percentage dry matter. Applied to MRLs expressed on a fresh weight basis
cBased on assumed bodyweight of 60 kg
Maximum anticipated dietary exposure: 0.15 mg/animal/day
Equivalent to: 0.0025 mg/kg bw
Equivalent to: 0.06 ppm in the diet
MFL (Based on the available lactating
cow feeding data):
6.5 ppm in the diet
Equivalent DDIL: 0.2 mg/kg bw

Pigs

Feed group Feed commodity % in the diet Feed intake, kg/animal/daya MRL, mg/kg % DMb Intake of mepiquat, mg/animal/dayc
Oilseeds
[30% maximum]
Cotton seed 30 0.75 0.2 - 0.15
Total   30 0.75     0.15
aBased on assumed feed consumption of 2.5 kg dry matter/day
bEstimate of percentage dry matter. Applied to MRLs expressed on a fresh weight basis
cBased on assumed bodyweight of 60 kg
Maximum anticipated dietary exposure: 0.15 mg/animal/day
Equivalent to: 0.0025 mg/kg bw
Equivalent to: 0.06 ppm in the diet
MFL (Based on the available lactating
cow feeding data):
6.5 ppm in the diet
Equivalent DDIL: 0.2 mg/kg bw

Poultry

Feed group Feed commodity % in the diet Feed intake, kg/animal/daya MRL, mg/kg % DMb Intake of mepiquat, mg/animal/dayc
Oilseeds [30% maximum] Cotton seed 30 0.05 0.2 - 0.009
Total   30 0.05     0.009
aBased on assumed feed consumption of 0.150 kg dry matter/day
bEstimate of percentage dry matter. Applied to MRLs expressed on a fresh weight basis
cBased on assumed bodyweight of 2 kg
Maximum anticipated dietary exposure: 0.009 mg/animal/day
Equivalent to: 0.0045 mg/kg bw
Equivalent to: 0.06 ppm in the diet
MFL (Based on the available poultry feeding data): 5 ppm in the diet
Equivalent DDIL: 0.43 mg/kg bw

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