Proposal – Maximum Nutrient Values for Small Ruminant
(Sheep and Goat) Feeds

July 2018

Purpose

As part of a comprehensive, multi-year regulatory modernization process, the Canadian Food Inspection Agency (CFIA) has initiated the renewal of the federal Feeds Regulations (Regulations) as one of several priorities identified for modernization.

The goal of renewing the Regulations is to develop a modernized risk- and outcome- based regulatory framework for feeds which:

  • safeguards feeds and the food production continuum
  • attains the most effective and efficient balance between fair and competitive trade in the market
  • minimizes regulatory burden

Modernization of the Regulations provides the opportunity to review feed controls, standards, labelling and other regulatory requirements. The purpose of this proposal is to:

  • review the nutrient content standards for sheep and goat feeds set out in Table 4 of Schedule I of the current Regulations which the CFIA has used to exempt complete feeds and some supplements from registration
  • recommend possible updates or amendments to the current requirements

Background and current situation

Table 4 of Schedule I was created and incorporated into the Feeds Regulations in the 1980s as a mechanism to exempt certain groups of feeds from mandatory registration. The original Table 4 established nutrient ranges (minimums and maximums) as exemption criteria for feeds for chickens, turkeys, swine, beef and dairy cattle, and sheep. In 1990, via two regulatory amendments, the table was first expanded to include horses, goats, ducks, and geese; and then for rabbits, mink, and salmonid fish. Since that time, there have been no other substantive changes to the table or to any of the nutrient ranges.

Currently, the feed can be exempted from registration if:

  • a complete feed provides nutrients which fall within the ranges listed in Table 4 or
  • a supplement has directions for use which would result in a complete feed that provides nutrients which fall within the Table 4 ranges

Feeds that provide nutrients which fall outside the ranges listed in Table 4, and that do not meet any additional exemption criteria, require assessment and registration by the CFIA prior to manufacture and sale.

In the case of small ruminant feeds, the original Table 4 established nutrient ranges in complete feed only. However, the National Research Council (1987 and 2007) report nutrient requirements for small ruminants on a total diet dry matter basis. Many factors – breed, size, reproduction stage, lactating stage, climate, type of forages and grains, on-farm feed management and practices, environmental conditions among others – have an impact on the variability of the daily feed intake. As total daily ration for ruminants includes forages, establishing nutrient ranges on the basis of complete feeds only does not take into consideration the nutrient contribution from the forage portion of the total daily diets and may lead to over supplementation of certain nutrients especially when the forages contain high level of nutrients and constitute a greater proportion of the daily diets.

As indicated in the 2016 Feed Regulatory Renewal Consolidated Modernized Framework Proposal, both the CFIA and stakeholders recognize that some of the values in Table 4 may no longer have the same nutritional relevancy that they did when the table was first introduced. Stakeholders have also indicated that they feel that Table 4 prevents innovation for new feed products. However, many of the maximum nutrient levels which are currently set out in Table 4 have health and safety implications that must be considered.

Proposal

It is proposed that:

  • Table 4 be removed from the Regulations and no longer serve as a trigger to register feeds based on specified ranges of nutrient content
  • maximum nutrient levels be established and incorporated by reference for sheep and goat feeds
  • the proposed maximums are established based on total daily diets rather than for complete feeds only

This proposed approach addresses stakeholder concerns regarding Table 4 and its relevance in current industry practices, as well as claims that the nutrient ranges provided in Table 4 impede new products from entering the marketplace. Furthermore, it addresses concerns regarding the harmful impact that higher levels of certain nutrients may have on livestock or the resulting food products, and underscores the modernized regulatory framework's focus on health and safety for humans, animals, and the environment. It is further proposed that:

  • minimum levels for nutrients will no longer be established, however, feeds will still be required to be suitable for their intended purpose and must meet an animal's nutritional requirements
  • maximum levels for nutrients will be established by species or classes of species, as appropriate
  • nutrient maximum levels will be incorporated by reference in the Feeds Regulations to facilitate updating, as necessary

Considerations

The domestic feed industry considers that the Table 4 nutrient ranges are out of date, and that this table is no longer an appropriate regulatory tool for feeds. However, there remains a continued need for an enforceable regulatory framework regarding maximum nutrient concentrations in livestock feeds for health and safety reasons. For instance, levels of certain vitamins in livestock rations (for example, vitamins A, D, and E) in excess of nutritional requirements can be harmful to livestock or can be concentrated into tissues that are used for human consumption, thus posing potential risk to human health. Similarly, certain minerals (for example, copper, iodine, phosphorus and zinc) fed in excess of livestock requirements can also contribute to increased human and environmental risks.

A significant proportion of minerals fed in excess of requirements are excreted into the environment via urine and feces. Consequently, even though the maximum tolerable level (MTL) of a given mineral may be significantly greater than the nutritional level, feeding at the maximum tolerable level may result in negative impact on the environment.

An analysis of sheep and goat nutritional requirements and maximum tolerable dietary nutrient levels was conducted by the CFIA with the following scope:

  • to determine those nutrient levels that may impact the health and safety of the respective livestock, humans, and environment
  • to determine those nutrient levels that support a nutritional purpose as opposed to a therapeutic purpose
  • to determine those nutrient levels that may produce residues in the resulting food that could be harmful to those consuming the products

Information sources used in the review and development of nutrient maximums in sheep and goat feeds included:

Appendix I sets out the proposed maximum nutrient values for sheep feeds.
Appendix II sets out the proposed maximum nutrient values for goat feeds.

The current Table 4 nutrient values to exempt feeds from registration are for the complete feed (grain portion of diets only) on an "as fed" basis (assumed 90% dry matter), assuming a fixed intake for all classes of small ruminants. In contrast, the proposed maximum nutrient levels are to be applied to the total dietary intake. These proposed maximums were derived taking into consideration typical total daily diets for the various classes of small ruminants and ranges for nutrient content of the forages (where known) as well as complete feeds (grain portion) and are reported on a "dry matter" basis. The proposed maximum nutrient concentration in the daily diet has been set high enough to provide flexibility to formulate nutritionally and environmentally sound diets. Where practical,

  • classes of sheep and goats with similar maximums have been grouped, or
  • a common and rounded nutrient value is presented across all classes

While the NRC requirements for vitamins are on a supplemental basis and the maximum values indicated in this proposal are on a total diet DM basis, the proposed values are over and above the NRC requirements such that contributions from the grain and forages, though variable, would not result in values exceeding the stated maximums.

Anticipated outcomes

This modernized regulatory approach to the oversight of maximum nutrient content in sheep and goat feeds would:

  • give regulated industry the flexibility to manufacture feeds with nutrient contents that meet their customers' needs without requiring pre-market assessment and authorization
  • allow the CFIA to maintain regulatory oversight for hazards that may negatively impact human or animal health or the environment
  • allow for timely updates to the standards as new information concerning specific nutrients is provided
  • reduce the regulatory burden on industry wishing to get innovative products into the marketplace

Stakeholders are being provided with an opportunity to comment on all proposals, including the maximum nutrient values being suggested for each species or class of species, before they are incorporated into a regulatory framework.

References: A complete bibliography is available upon request.

Have your say

The CFIA is seeking feedback on the proposal to modify the regulatory requirements related to maximum nutrient content in livestock feed:

  • Do you have any concerns with the proposal to remove the Table 4 nutrient levels from the Feeds Regulations and no longer exempting feeds from registration based on the nutrient content of the feeds?
  • Do you have any concerns with the proposal to establish maximum nutrient values for livestock feeds?
  • Do you have any concerns with the proposed maximum nutrient values outlined in Appendix I and II for sheep and goat feeds, respectively?
  • Would the proposed amendments to the Feeds Regulations be effective in protecting human and animal health and the environment?
  • Are there options not mentioned in this proposal that should be explored?
  • Any additional feedback?

We strongly encourage you to provide your input and feedback, which is critically important to the success of the regulatory modernization initiative.

Please send written comments by 08/17/18 to:

Sergio Tolusso
Canadian Food Inspection Agency
Animal Feed Division
59 Camelot Drive
Ottawa, ON K1A 0Y9

Email: Sergio.tolusso@canada.ca
Fax: 613-773-7565

Appendix I – Proposed maximum nutrient values fo sheep feeds

Sheep classes and average intakes: (dry matter basis (DM))
Class Range of DM intake
(% body weight (BW)) Table Note 1
Forages
Rams 1.6 to 2 25 to 30% minimum
Ewes (Breeding and Lactating) 1.6 to 5 25 to 30% minimum
Market lambs 1.5 to 6 Up to 20%

Table Note

Table Note 1

Adapted from NRC 2007 Nutrient Requirements of Small Ruminants Washington, DC, The National Academies Press.

Return to table note 1  referrer

Macro-minerals

Calcium (Ca)
Class Current
(% of complete feed, as fed)
Proposed
(% of diet DM)
Sheep (All) 2 1.5

Considerations:

  • calcium (Ca) requirements for sheep are estimated by (NRC 2007) using the factorial method; they vary between 0.16% and 0.37% of diet DM based on the type of animal and stage of production
  • maximum tolerable level of Ca in sheep feed is 1.5% of diet DM (NRC 2005)
  • calcium levels greater than 1.5% of diet DM may decrease feed intake, and/or negatively affect the metabolism of other minerals – namely phosphorus (P) and zinc (Zn) (NRC 2005)
Phosphorus (P)
Class Current
(% of complete feed, as fed)
Proposed
(% of diet DM)
Sheep (All) 0.6 0.6

Considerations:

  • phosphorus (P) requirements for sheep are estimated by (NRC 2007) using the factorial method; they vary between 0.15% and 0.31% of diet DM based on the type of animal and stage of production
  • phosphorus supplied in surplus of dietary needs is excreted in the manure, contaminates runoff water, and leads to eutrophication; a significant environmental concern (NRC 2007)
  • high dietary P may lead to urolithiasis in sheep (NRC 2005)
  • maximum tolerable level for P in sheep feed (assuming sufficient Ca) is 0.6% diet DM (NRC 2005)
Magnesium (Mg)
Class Current
(% of complete feed, as fed)
Proposed
(% of diet DM)
Sheep (All) 0.5 0.6

Considerations:

  • magnesium (Mg) requirements for sheep are estimated by (NRC 2007) using the factorial method; they vary between 0.08% and 0.12% of diet DM based on the type of animal and stage of production
  • (NRC 2005) states that the maximum tolerable dietary level of Mg in ruminant feed is 0.6% diet DM
  • excessive dietary Mg in sheep may lead to lethargy, diarrhea, decreased feed intake and decreased performance (NRC 2007)
Sodium (Na)
Class Current
(% of complete feed, as fed)
Proposed
(% of diet DM)
Sheep (All) 1.2 1.6

Considerations:

  • sodium (Na) requirements for sheep are estimated by (NRC 2007) using the factorial method; they vary between 0.04% and 0.08% of diet DM based on the type of animal and stage of production
  • (NRC 2005) reports the maximum tolerable level of sodium chloride (NaCl) in feed as 4% diet DM (approximately 1.6% Na)
  • decreased animal performance can be observed at levels as low as 2.0% dietary NaCl (approximately 0.8% Na) (Markus 2013) but can be ameliorated with access to fresh water, as sheep increase water intake and urine excretion of Na when fed high Na diets (NRC 2007)
Potassium (K)
Class Current
(% of complete feed, as fed)
Proposed
(% of diet DM)
Sheep (All) 3 2

Considerations:

  • potassium (K) requirements for sheep are estimated by (NRC 2007) using the factorial method; they vary between 0.41% and 0.50% of diet DM based on the type of animal and stage of production
  • (NRC 2005) states that the maximum tolerable dietary level of K in ruminant feed is 2% diet DM
  • potassium excess may lead to grass tetany (hypomagnesemia) and/or milk fever (hypocalcaemia) (NRC 2007)
  • potassium excretion leading to environmental contamination is also of increasing concern and necessitates precision feeding (NRC 2007)
Sulfur (S)
Class Current
(% of complete feed, as fed)
Proposed
(% of diet DM)
Sheep (All) 0.4 0.4

Considerations:

  • sulfur (S) requirements for sheep are estimated by (NRC 2007) using the factorial method; they vary between 0.14% and 0.16% of diet DM based on the type of animal and stage of production
  • dietary S requirements may be greater when formulating diets with urea (or other non-protein nitrogen sources), with mature forages, and/or with forages grown on S deficient soils
  • NRC (2005) indicates that setting maximum tolerable level for S in sheep feed is 0.3% diet DM in high concentrate diets and 0.5% diet DM in high forage diet
    • high concentrate diets refer to diets with less than 15% forage (specifically market lambs)
    • high forage diets refer to diets with greater than 40% forage
  • extending the current 0.4% to a total diet DM basis for all sheep is protective of those with high forage diets and accounts for market lambs presumably being fed high concentrate diets
  • sulfur levels in forage crops and feed ingredients considering usage rates (NRC 2016) were considered
  • excessive dietary S interferes with copper (Cu) and selenium (Se) metabolism and may lead to polioencephalomalacia (NRC 2007)

Trace Minerals

Cobalt (Co)
Class Current
(mg/kg of complete feed, as fed)
Proposed
(mg/kg of diet DM)
Sheep (All) 10 1

Considerations:

  • fundamentally, ruminants do not have a dietary requirement for cobalt (Co); but, ruminal micro-organisms require Co for the synthesis of vitamin B12 (NRC 2007)
  • (NRC 2007) recommends a minimum level of 0.10 to 0.20 mg Co/kg diet DM
  • (Wang, Kong et al. 2007) and (Bishehsari, Tabatabaei et al. 2010) conducted trials in which supplementation of 0.50 mg Co/kg diet DM improved average daily gain and digestibility compared to 0.25 mg Co/kg diet DM and/or 1 mg Co/kg diet DM
  • maximum tolerable level of Co in sheep feed is reported as 25 mg/kg diet DM. However, there may be human health implications (via kidney Co concentration) associated with animals consuming the maximum amounts of Co/kg feed (NRC 2005)
  • Co and Co compounds pose a risk to workers during mixing and feeding due to their dusting potential and presumed carcinogenicity after inhalation (EFSA FEEDAP Panel (EFSA Panel on Additives and Products or Substances used in Animal Feed) 2009, European Food Safety Authority 2012)
  • European Food Safety Authority suggests a maximum content of 1 mg Co/kg diet DM (EFSA FEEDAP Panel (EFSA Panel on Additives and Products or Substances used in Animal Feed) 2009, European Food Safety Authority 2012)
Copper (Cu)
Class Current
(mg/kg of complete feed, as fed)
Proposed
(mg/kg of diet DM)
Sheep (All) 8 (added) 15

Considerations:

  • copper (Cu) requirements for sheep are estimated by (NRC 2007) using the factorial method; they vary between 3 and 7.12 mg Cu/kg diet DM based on the type of animal and stage of production
  • (NRC 2005) reports the maximum tolerable level of Cu in sheep feeds is 15 mg/kg diet DM
  • maximum tolerable level assumes the ration contains normal levels of molybdenum (1-2 mg/kg diet DM) and sulfur (0.15-0.25 mg/kg diet DM). If these minerals are present in greater quantities, some sheep may be susceptible to Cu deficiency; and if present in lower quantities, some sheep may be susceptible to Cu toxicosis (NRC 2005)
  • reports of copper toxicosis and chronic copper poisoning (CPP) are well documented in sheep; symptoms include excessive copper accumulation in the liver, haemoglobinuria, haemoglobianemia and jaundice (NRC 2007)
Iodine (I)
Class Current
(mg/kg of complete feed, as fed)
Proposed
(mg/kg of diet DM)
Lactating sheep 10 1.3
Non-lactating sheep 10 2

Considerations:

  • (NRC 2007) estimates the iodine (I) requirements for growing and mature (non-lactating) sheep as 0.5 mg/kg diet DM and for lactating ewes as 0.8 mg/kg diet DM
  • maximum tolerable level of I in sheep feed is reported as 50 mg/kg diet DM (NRC 2005)
  • (European Food Safety Authority 2013) states that iodine concentrations in foods of animal origin represent a significant risk to consumers. To ameliorate consumer risk, the proposed maximum is lower than both the MTL and current maximum in complete feed
  • children should be consuming approximately 200 μg/kg (Castro et al. 2010)
  • current bulk tank samples (of cow's milk) are testing at approximately 300 μg/kg, which rationalizes the move to reduce I in feed (Castro et al. 2010)
  • sheep milk that has been tested is comparable to cow milk (Rozenska 2011)
  • sheep proposal for I mirrors that for lactating dairy (1.3 mg/kg)
Iron (Fe)
Class Current
(mg/kg of complete feed, as fed)
Proposed
(mg/kg of diet DM)
Sheep (All) 250 500

Considerations:

  • iron (Fe) requirements for sheep are estimated by (NRC 2007) using the factorial method; they vary between 5.41 and 69.11 mg/kg diet DM based on the type of animal and stage of production
  • (Munday and Manns 1989) reported that iron doses of 100 mg/kg/day was protective against sporidesmin toxicity
  • maximum tolerable level (MTL) of Fe in sheep feed is reported as 500 mg/kg diet DM (NRC 2005)
  • forages are abundant in Fe; as such, the maximum safety limit is set to the MTL to accommodate the high intrinsic level that may be present in forages
  • excessive iron supplementation can result in liver damage and copper deficiency (NRC 2007)
Manganese (Mn)
Class Current
(mg/kg of complete feed, as fed)
Proposed
(mg/kg of diet DM)
Sheep (All) 200 150

Considerations:

  • concentration of manganese (Mn) in forages varies greatly depending on plant species, soil pH and soil drainage
  • Mn requirements for sheep are estimated by (NRC 2007) using the factorial method; they vary between 5.14 and 25.58 mg/kg diet DM based on the type of animal and stage of production
  • maximum tolerable level of Mn in sheep feed is reported as 2000 mg/kg diet DM (NRC 2005)
  • current authorised maximum of Mn in complete feed in the European Union is 150 mg Mn/kg diet (European Commission 2003); at this level manganese is considered safe for the animal, worker, consumer, and environment
Selenium (Se)
Class Current
(mg/kg of complete feed, as fed)
Proposed
(mg/kg of diet DM)
Sheep (All) 0.3 (added) 1 (total)

Considerations:

  • selenium (Se) concentrations in feedstuff range from 0.01- 0.3 mg/kg depending on Se content in the soil and pH (NRC 2007)
  • Se requirements for sheep are estimated by (NRC 2007) using the factorial method; they vary based on the type of animal and stage of production
  • maximum tolerable level of Se in ruminant feed is 5 mg/kg diet. However, this value was set considering animal health (only) and lower levels are necessary to avoid excessive accumulation in edible tissues (NRC 2005)
  • European Food Safety Authority suggests a maximum of 0.5 mg Se/kg diet (EFSA Panel on Additives and Products or Substances used in Animal Feed 2016)
  • the CFIA provided Health Canada with data on Se transfer to milk, meat, and eggs. Health Canada assessed this data and has indicated that 1 mg/kg total selenium in the diet should not result in Se concentrations of concern in foods of animal origin
Zinc (Zn)
Class Current
(mg/kg of complete feed, as fed)
Proposed
(mg/kg of diet DM)
Sheep (All) 150 150

Considerations:

  • zinc (Zn) requirements for sheep are estimated by (NRC 2007) using the factorial method; they vary between 18.57 and 35.04 mg/kg diet DM based on the type of animal and stage of production
  • (Wang, Zhu et al. 2006) found no difference in performance parameters in lambs supplemented with 50, 100 or 150 mg Zn/kg diet DM but did observe a negative effect of Zn supplementation on vitamin B12 status in lambs above 100 mg Zn/kg diet DM
  • maximum tolerable level of Zn in sheep feed is reported as 300 mg/kg diet DM (NRC 2005)
  • increases in sediment bound zinc have been positively associated with livestock densities (Smith, K.J. Hall et al. 2007) and, as a result, excretion of zinc from livestock is of increasing environmental concern (Monteiro, Lofts et al. 2010)
  • European Union authorized maximum content for Zn in complete feedingstuffs for "other species" is 150 mg/kg
  • EFSA (2014, 2015) proposes a reduction in zinc content of feedstuffs to 100 mg/kg DM to minimize environmental damage
  • use of Zn supplements (greatly exceeding requirements) in sheep feed also threatens food safety through the potential emergence and spread of antibiotic resistance pathogens. As such, the maximum levels are set lower than the current recommended MTL levels.

Vitamins

Vitamin A
Class Current
(IU/day)
Proposed
(IU/kg of diet DM)
Lambs for rearing
(≤2 months old)
75,000 16,000
Sheep for fattening
(≥2 months old)
75,000 10,000

Considerations:

  • 104.7 IU of vitamin A/kg of BW is recommended for small ruminants (NRC 2007)
    • for example, a 100 kg ewe would require 10,470 IU (104.7 IU/kg BW*100 kg) of vitamin A/day
  • (Markus 2013) estimates sheep vitamin A requirements between 2300 IU/kg diet DM and 5000 IU/kg diet DM based on type of animal and stage of production
  • presumed safe levels for vitamin A in sheep is 45 000 IU/kg diet (NRC 1987)
  • FEEDAP proposal from 2008 (EFSA, 2008) balanced equally between assuring the safety of consumers (avoiding excess retinol intake) and of target animals (avoiding negative effects on performance and the economics of production). As a guide the maximum contents proposed were based on double the allowances
  • European Food Safety Authority 2013 expanded on the FEEDAP Panel 2008 states that all exposure calculations demonstrate that liver is the only food of animal origin for which consumption poses a risk to adult consumers. This risk could be greatly reduced (but not eliminated) if the new levels proposed by EFSA for a reduction of the maximum vitamin A are implemented. EFSA (2013) provided some modification to improve its practicability and proposed the following maximum contents for vitamin A:
    • 16,000 IU/kg in feeds for lambs and kids for rearing in the first two months of life
    • 10,000 IU/kg in feeds for sheep and goats for fattening
Vitamin D
Class Current
(IU/day)
Proposed
(IU/kg of diet DM)
Sheep (All) 7,500 2,200

Considerations:

  • vitamin D requirements proposed by (NRC 2007) are in line with those in previous publications (NRC 1980; NRC 1981, 1985). 5.6 IU vitamin D/kg BW is required for maintenance and early pregnancy; an additional 213 IU/day in late pregnancy, 760 IU/kg milk production during lactation, and 54 IU/day for every 50 g daily weight gain is also required:
    • for example, a 100 kg ewe in late pregnancy would require 773 IU of vitamin D ((5.6 IU/kg BW*100 kg) + 213 IU) per day
  • safe upper level of vitamin D in sheep is reported as 25,000 IU/kg diet when exposure is less than 60 days and 2,200 IU/kg diet when exposure is greater than 60 days (NRC 1987)
  • vitamin D supplied in excess is associated with hypercalcemia and calcification of soft tissues (NRC 1987)
Vitamin E
Class Current
(IU/day)
Proposed
(IU/kg of diet DM)
Sheep (All) NRS (No requirement specified) 1250

Considerations:

  • 5.3 IU vitamin E/kg body weight (BW) is the minimum recommendation reported by (NRC 2007)
  • NRC (1987), noted most species should tolerate at least 20 times nutritionally adequate levels of vitamin E, and a presumed upper safe level is 75 IU/kg-BW. With feed intakes ranging up to 6% BW for some growing lambs, a presumed upper safe level is 1250 IU/kg DM
  • EFSA (2010) indicates that more than 200 IU vitamin E/kg complete feeds is not desirable in feeding practice
  • higher levels ofVitamin E has a potential non-feed/therapeutic use for improving immune function (Petersson et al., 2010)

Appendix II – Proposed maximum nutrient values for goat feeds

Goat classes and average intakes: (dry matter basis (DM))
Class Range of DM intake
(% body weight (BW)) Table Note 2
Forages
Mature bucks 1.9 to 2.7 25 to 30% minimum
Mature does (Dairy; Breeding and Lactating) 2.0 to 7.7 25 to 30% minimum
Mature does (Non-Dairy; Breeding and Lactating) 1.7 to 5.0 25 to 30% minimum
Growing kids (Dairy) 2.9 to 6.0 Up to 20%
Growing kids (non-Dairy) 2.4 to 5.5 Up to 20%

Table Notes

Table Note 2

Adapted from NRC 2007 Nutrient Requirements of Small Ruminants Washington, DC, The National Academies Press.

Return to table note 2  referrer

Macro-minerals

Calcium (Ca)
Class Current
(% of complete feed, as fed)
Proposed
(% of diet DM)
Goat (All) 2 1.5

Considerations:

  • calcium (Ca) requirements for goats are estimated by (NRC 2007) using the factorial method; they vary between 0.14% and 0.60% of diet DM based on the type of animal and stage of production
  • maximum tolerable level of Ca in goat feed is 1.5% diet DM (NRC 2005)
  • calcium levels greater than 1.5% of diet DM may decrease feed intake, and/or negatively affect the metabolism of other minerals – namely Phosphorus (P) and Zinc (Zn) (NRC 2005)
Phosphorus (P)
Class Current
(% of complete feed, as fed)
Proposed
(% of diet DM)
Goat (All) 1 0.6

Considerations:

  • phosphorus (P) requirements for goats are estimated by (NRC 2007) using the factorial method; they vary between 0.13% and 0.33% of diet DM based on the type of animal and stage of production
  • maximum tolerable level for P in small ruminant feed is 0.6% diet DM (NRC 2007)
  • phosphorus supplied in surplus of dietary needs is excreted in the manure, contaminates runoff water, and leads to eutrophication, which is a significant environmental concern (NRC 2007)
Magnesium (Mg)
Class Current
(% of complete feed, as fed)
Proposed
(% of diet DM)
Goat (All) 0.5 0.6

Considerations:

  • magnesium (Mg) requirements for goats were estimated by (NRC 2007) using the factorial method; they vary between 0.05% and 0.14% of diet DM based on the type of animal and stage of production
  • (NRC 2005) states that the maximum tolerable dietary level of Mg in ruminant feed is 0.6% diet DM
  • excessive dietary Mg may lead to lethargy, diarrhea, decreased feed intake and, as a result decreased performance (NRC 2007)
  • high dietary magnesium intake has also been associated with urolithiasis in goats (NRC 2007)
Sodium (Na)
Class Current
(% of complete feed, as fed)
Proposed
(% of diet DM)
Goat (All) 1.2 1.6

Considerations:

  • sodium (Na) requirements for goats are estimated by (NRC 2007) using the factorial method; they vary between 0.05% and 0.11% of diet DM based on the type of animal and stage of production
  • (Gomes, Oliveira-Pascoa et al. 2011) suggested that the nutritional requirements for Na proposed by the National Research Council (NRC 2007) were greater than what is actually required in growing Saanen goat kids
  • (NRC 2005) reports the maximum tolerable level of sodium chloride (NaCl) in feed as 4% diet DM (approximately 1.6% Na); however, decreased animal performance in goats can be observed at levels as low as 2% dietary NaCl (approximately 0.8% Na) (Markus 2013)
  • goats increase water intake and urine excretion of Na when fed high Na diets (NRC 2007)
Potassium (K)
Class Current
(% of complete feed, as fed)
Proposed
(% of diet DM)
Goat (All) NRS 2

Considerations:

  • potassium (K) requirements for goats are estimated by (NRC 2007) using the factorial method; they vary between 0.40% and 0.70% of diet DM based on the type of animal and stage of production
  • (Gomes, Oliveira-Pascoa et al. 2011) suggested that the nutritional requirements for K proposed by the National Research Council (NRC 2007) were greater than what is actually required in growing Saanen goat kids
  • (NRC 2005) states that the maximum tolerable dietary level of K in ruminant feed is 2% diet DM
  • potassium excess may lead to grass tetany (hypomagnesemia) and/or milk fever (hypocalcaemia) (NRC 2007)
  • potassium excretion leading to environmental contamination is also of increasing concern and necessitates precision feeding (NRC 2007)
Sulfur (S)
Class Current
(% of complete feed, as fed)
Proposed
(% of diet DM)
Goat (All) NRS 0.4

Considerations:

  • (NRC 2007) reports 0.22% sulfur (S) diet DM is required for maintenance, gestation and growing goats while 0.26% S diet DM is required for lactating does
  • dietary S requirements may be greater when formulating diets with urea (or other non-protein nitrogen sources), with mature forages, and/or with forages grown on S deficient soils
  • maximum tolerable level for S in ruminant feed is 0.3% diet DM in high concentrate diets and 0.5% diet DM in high forage diets (NRC 2005)
    • High concentrate diets refer to diets with less than 15% forage
    • High forage diets refer to diets with greater than 40% forage
  • applying the current 0.4% sheep to a total diet DM basis for all goats should suffice given it is protective of those with high forage diets and does not appear to be a current issue for market lambs presumably being fed high concentrate diet
  • sulfur levels in forage crops and feed ingredients considering usage rates (NRC 2016) were considered
  • excessive dietary S interferes with copper (Cu) and selenium (Se) metabolism and may lead to polioencephalomalacia (NRC 2007)

Trace Minerals

Cobalt (Co)
Class Current
(mg/kg of complete feed, as fed)
Proposed
(mg/kg of diet DM)
Goat (All) 10.0 1

Considerations:

  • ruminants generally do not have a dietary requirement for cobalt (Co),but ruminal micro-organisms require cobalt for the synthesis of vitamin B12 (NRC 2007)
  • (NRC 2007) recommends a minimum level of 0.11 Co/kg diet DM in goat feed
  • maximum tolerable level of Co in goat feed is 25 mg/kg diet DM. However, there may be human health implications (via kidney Co concentration) associated with animals consuming the maximum amounts of Co/kg feed (NRC 2005).
  • Co and Co compounds pose a risk to workers during mixing and feeding due to their dusting potential and presumed carcinogenicity after inhalation (EFSA FEEDAP Panel (EFSA Panel on Additives and Products or Substances used in Animal Feed) 2009, European Food Safety Authority 2012)
  • European Food Safety Authority recommends a maximum content of 1 mg Co/kg diet DM (EFSA FEEDAP Panel (EFSA Panel on Additives and Products or Substances used in Animal Feed) 2009, European Food Safety Authority 2012)
Copper (Cu)
Class Current
(mg/kg of complete feed, as fed)
Proposed
(mg/kg of diet DM)
Goat (All) 40 40

Considerations:

  • copper (Cu) requirements recommended by (NRC 2007) are: 15 mg Cu/kg diet DM for lactating goats, 20 mg Cu/kg diet DM for mature goats/bucks and 25 mg Cu/kg diet DM for growing goats
  • (NRC 2007) suggests that goats (especially meat goats) have a greater tolerance for copper than both sheep (MTL: 15 mg Cu/kg feed) and cattle (MTL: 40 mg Cu/kg feed); however, based on lack of evidence,( NRC 2007) proposes using the maximum tolerable level of Cu in cattle feed (40 mg Cu/kg feed) for goat management
  • (Huang, Wang et al. 2013, Huang, Wang et al. 2014) estimates the maximum tolerable limit for copper in goats as approximately 640 mg/kg diet DM
  • (EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) 2016) reports that copper levels considered safe for animals can result in substantial excretion of copper and a significant environmental load; they propose lowering copper maximums in feed
  • use of Cu supplements (greatly exceeding requirements) in goat feed threatens food safety through the potential emergence and spread of antibiotic resistance pathogens
Iodine (I)
Class Current
(mg/kg of complete feed, as fed)
Proposed
(mg/kg of diet DM)
Lactating Goats 10 1.3
Non-Lactating Goats 10 2

Considerations:

  • (NRC 2007) estimates the iodine (I) requirements for growing and mature (non-lactating) goats as 0.5 mg/kg diet DM and for lactating does as 0.8 mg/kg diet DM
  • maximum tolerable level of I in sheep and cattle feed is reported as 50 mg/kg diet DM (NRC 2005)
    • it is assumed that this level can be extrapolated to goat feed
  • (Lengemann 1970) demonstrates that goats concentrate more iodine in their milk than cows under similar conditions
  • goat milk contains greater levels of I than cows (Flachowsky 2007)
  • (European Food Safety Authority 2013) states that iodine concentrations in food of animal origin at the current maximum levels of I in feed (10.0 mg I/kg feed) represent a significant risk to consumers. To ameliorate consumer risk, the proposed maximum is lower than the current maximum in complete feed
Iron (Fe)
Class Current
(mg/kg of complete feed, as fed)
Proposed
(mg/kg of diet DM)
Goat (All) 500 500

Considerations:

  • (NRC 2007) estimates the iron (Fe) requirements of goats as 95 mg/kg diet DM for growing goats and as 35 mg/kg diet DM for pregnant/lactating goats
    • an additional 5 mg Fe/kg diet is recommended for Mohair (Angora) goats
  • maximum tolerable level of Fe in sheep and cattle feed is reported as 500 mg/kg diet DM (NRC 2005)
    • this level has been extrapolated to goat feed
  • forages are abundant in Fe; as such, the maximum safety limit is set the MTL to accommodate the high intrinsic level that may be present in forages
  • iron toxicity can result in liver damage and copper deficiency (NRC 2007)
Manganese (Mn)
Class Current
(mg/kg of complete feed, as fed)
Proposed
(mg/kg of diet DM)
Goat (All) 200 150

Considerations:

  • concentration of manganese (Mn) in forages varies greatly depending on plant species, soil pH and soil drainage
  • manganese requirements for goats are estimated by (NRC 2007) using the factorial method; they vary between 7.71 and 23.94 mg/kg diet DM based on the type of animal and stage of production
  • maximum tolerable level for Mn in sheep and cattle diets is 2,000 mg/kg diet DM (NRC 2005)
    • this level has been extrapolated to goat feed
  • current European Union authorised max total content of manganese in complete feed is set at 150 mg/kg for goats (European Commission 2003); at this level manganese is considered safe for the animal, worker, consumer, and environment
Selenium (Se)
Class Current
(mg/kg of complete feed, as fed)
Proposed
(mg/kg of diet DM)
Goat (All) 0.3 (added) 1 (total)

Considerations:

  • selenium (Se) requirements for goats are estimated by (NRC 2007) using the factorial method; they vary based on the type of animal and stage of production
  • maximum tolerable level of Se in ruminant feed is reported as 5 mg/kg diet. However, this value was set considering animal health only and lower levels are necessary to avoid excessive accumulation in edible tissues (NRC 2005)
  • current European Union authorised maximum total content of selenium in complete feed is set at 0.5 mg/kg for goats (European Commission 2003)
  • The CFIA provided Health Canada with data on Se transfer to milk, meat, and eggs. Health Canada assessed this data and has indicated that 1 mg/kg total selenium in the diet should not result in Se concentrations of concern in foods of animal origin
Zinc (Zn)
Class Current
(mg/kg of complete feed, as fed)
Proposed
(mg/kg of diet DM)
Goat (All) 250 150

Considerations:

  • zinc (Zn) requirements for goats are estimated by (NRC 2007) using the factorial method; they vary between 5.41 and 63.15 mg/kg diet DM based on the type of animal and stage of production
  • maximum tolerable level of Zn in sheep feed is reported as 300 mg/kg diet DM (NRC 2005)
    • this level has been extrapolated to goat feed
  • increases in sediment bound zinc have been positively associated with livestock densities (Smith, K.J. Hall et al. 2007) and, as a result, zinc excretion from livestock is of increasing environmental concern (Monteiro, Lofts et al. 2010)
  • (European Food Safety Authority 2014) proposes a reduction in zinc content of feedstuff to 100 mg/kg to lessen environmental damage. As such, the proposed maximum is lower than the MTL for animal health
  • use of zinc supplements (greatly exceeding requirements) in goat feed also threatens food safety through the potential emergence and spread of antibiotic resistance pathogens

Vitamins

Vitamin A
Class Current
(IU/day)
Proposed
(IU/kg of diet DM)
Kids for Rearing
(≤2 months old)
40,000 16,000
Goats for Fattening
(≥2 months old)
40,000 10,000

Considerations:

  • 104.7 IU of vitamin A/kg of BW is recommended for small ruminants (NRC 2007):
    • For example, a 100 kg doe would require 10,470 IU (104.7 IU/kg BW*100 kg) of vitamin A/day
  • presumed safe level for vitamin A in goats is 45 000 IU/kg diet (NRC 1987)
  • 2008 FEEDAP proposal (EFSA, 2008) balanced equally between assuring the safety of consumers (avoiding excess retinol intake) and of target animals (avoiding negative effects on performance and the economics of production). As a guide the maximum contents proposed were based on double the allowances.
  • European Food Safety Authority 2013 expanded on the FEEDAP Panel 2008 states that all exposure calculations demonstrate that liver is the only food of animal origin for which consumption poses a risk to adult consumers. This risk could be greatly reduced (but not eliminated) if the new levels proposed by EFSA for a reduction of the maximum vitamin A are implemented. EFSA (2013) provided some modification to improve its practicability and proposed the following maximum contents for vitamin A:
    • 16 000 IU/kg in feeds for lambs and kids for rearing in the first two months of life
    • 10 000 IU/kg in feeds for sheep and goats for fattening
Vitamin D
Class Current
(IU/day)
Proposed
(IU/kg of diet DM)
Goat (All) 3,000 2,200

Considerations:

  • vitamin D requirements proposed by (NRC 2007) are in line with those in previous publications (NRC 1980; NRC 1981, 1985). 5.6 IU vitamin D/kg BW is required for maintenance and early pregnancy; an additional 213 IU/day in late pregnancy, 760 IU/kg during lactation, and 54 IU/day for every 50 g daily weight gain is also required:
    • for example, a 100 kg doe in late pregnancy would require 773 IU of vitamin D ((5.6 IU/kg BW*100 kg) + 213 IU) per day
  • safe upper level of vitamin D in small ruminants is reported as 25 000 IU/kg diet when exposure is less than 60 days and 2 200 IU/kg diet when exposure is greater than 60 days (NRC 1987)
  • vitamin D supplied in excess is associated with hypercalcemia and calcification of soft tissues (NRC 1987)
Vitamin E
Class Current
(IU/day)
Proposed
(IU/kg of diet DM)
Goat (All) NRS 1000

Considerations:

  • 5.3 IU vitamin E/kg body weight (BW) is the minimum recommendation reported by (NRC 2007)
  • NRC (1987), noted most species should tolerate at least 20 times nutritionally adequate levels of vitamin E, and a presumed upper safe level is 75 IU/kg-BW. With feed intake ranging up to 7.7% BW for goats (NRC 2007), a presumed upper safe level of 1000 IU/kg DM is proposed
  • EFSA (2010) indicates that more than 200 IU vitamin E/kg complete feedingstuffs is not desirable in feeding practice