PUBLIC REVIEW DRAFTDRAFT UGANDA 
STANDARDDUS DARS  939 
First Edition  
2024-mm-dd
Reference number  
DUS DARS 939: 2023 
© UNBS 2024 Feed maize  — Specification  PUBLIC REVIEW DRAFTDUS DARS 939: 202 3 
ii                © UNBS  2024  - All rights reserved  
 Compliance with this standard does not, of itself confer immunity from legal obligations  
A Uganda Standard does not purport to include all necessary provisions of a contract. Users are 
responsible for its correct applicatio n 
© UNBS 2024  
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilised in any 
form or by any means, electronic or mechanical, including photocopying and microfilm, without prior written 
permission from UNBS . 
Requests for permission to reproduce this document should be addressed to  
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 PUBLIC REVIEW DRAFTDUS DARS 939: 202 3 
© UNBS  2024 - All rights reserved                 iii National foreword  
Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry of Trade, Industry and 
Cooperatives established under Cap 327, of the Laws of Uganda, as amen ded. UNBS is mandated to co -
ordinate the elaboration of standards and is  
(a) a member of International Organisatio n for Standardisation (ISO),  
(b) a contact point for the WHO/FAO Codex Alimentarius Commission on Food Standards, and  
(c) the National Enquiry Point on TBT Agreement of the World Trade Organisation (WTO).  
The work of preparing Uganda Standards is carried out through Technical Committees. A Technical 
Committee is established to deliberate on standards in a given field or area and consists of representatives of 
consumers, traders, ac ademicians, manufacturers, government and other stakeholders.  
Draft Uganda Standards adopted by the Technical Committee are widely circulated to stakeholders and the 
general public for comments. The committee reviews the comments before recommending the dr aft standards 
for approval and declaration as Uganda Standards by the National Standards Council.  
This Draft Uganda Standard, DUS DARS 393: 202 3, Feed maize — Specification , is identical with and has 
been reproduced from an African  Standard, DARS 393: 2023 , Feed maize — Specification , and adopted  as a 
Uganda Standard . 
The committee responsible for this document is Technical Committee UNBS/TC 210, Animal feeds and 
feeding stuffs . 
Wherever the words, “ African  Standard " appear, they should be replaced by "Uganda Standard ". AFRICAN 
STANDARD  DARS  
939  
Second  Edition 20 23 
 
 Reference No. ARS 939:2023(E) 
ICS 67.060  
 
 
© ARSO 20 23 
  
 
 
 
 
 
 
 
 
 
Feed maize — Specification  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 DARS 939:20 23 
ii © ARSO 20 23 — All rights reserved   
Table of contents  
 
1 Scope  ................................ ................................ ................................ ................................ .............  1 
2 Normative references  ................................ ................................ ................................ .....................  1 
4 Quality requirements  ................................ ................................ ................................ ......................  3 
5. Contaminants  ................................ ................................ ................................ ................................ . 3 
6 Hygiene  ................................ ................................ ................................ ................................ ..........  4 
7 Packaging and Labelling  ................................ ................................ ................................ ................  4 
8. Sampling  ................................ ................................ ................................ ................................ .........  5 
 
 DARS 939:20 23 
© ARSO 20 23 — All rights reserved  iii  
Foreword  
 
The African Organization for Standardization (ARS) is an African intergovernmental organization 
made up of the United Nations Economic Commission for Africa (UNECA) and the Organization of 
African Unity (AU). One of the fundamental mandates of ARSO is to develop and harmoniz e African 
Standards (ARS) for the purpose of enhancing Africa’s internal trading capacity, increase Africa’s 
product and service competitiveness globally and uplift the welfare of African communities. The work 
of preparing African  Standards is normally carried out through ARSO  technical committees. Each 
Member State  interested in a subject for which a technical committee has been established has the 
right to be represented on that committee. International organizations, Regional Economic 
Communities (RECs), governmental and non -governmental  organizations , in liaison with ARSO , also 
take part in the work.  
 
ARSO  Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.  
 
The main task of technical committees is to prepare ARSO  Standards. Draft ARSO  Standards 
adopted by the technical committees are circulated to the member bodies for voting. Publication as an 
ARSO  Standard requires approval by at least 75 % of the member bodies casting a vote.  
 
Attention is drawn to the possibility that some of the elements of this document may be the subject of 
patent rights. ARSO  shall not be held responsible for identifying any or all such patent rights.  
 
This African Standard was prepared by the ARSO Technical Harmonization Committee on Agriculture 
and Food Products (ARSO/THC 02). 
 
 
 
 
 
© African Organisation for Standardisation  2016 — All rights reserved* 
 
ARSO Central Secretariat  
International House 3rd Floor  
P. O. Box 57363 — 00200 City Square  
NAIROBI, KENYA  
 
Tel. +254 -20-2224561, +254 -20-311641, +254 -20-311608  
Fax: +254 -20-218792  
E-mail: arso@arso -oran.org  
Web: www.arso -oran.org  
 
* © 2016 ARSO — All rights of exploitation reserved worldwide for African Member States’ NSBs.  
 DARS 939:20 23 
iv © ARSO 20 23 — All rights reserved   
 
Copyright notice  
 
This ARSO document is copyright -protected by ARSO. While the reproduction of this document 
by participants in the ARSO standards development process is permitted without prior 
permission from ARSO, neither this document nor any extract from it may be reproduced, stored 
or transmitted in any form for any other purpose without prior written permission from ARSO.  
 
Requests for permission to reproduce this document for the purpose of selling it should be 
addressed as shown below or to ARSO’s member body in the country of the requester:  
 
 
© African Organisation for Standardisation 201 6 — All rights reserved  
 
ARSO Central Secretariat  
International House 3rd Floor  
P.O. Box 57363 — 00200 City Square  
NAIROBI, KENYA  
 
Tel: +254 -20-2224561, +254 -20-311641, +254 -20-311608  
Fax: +254 -20-218792  
 
E-mail: arso@arso -oran.org  
Web: www.arso -oran.org  
 
Reproduction for sales purposes may be subject to royalty payments or a licensing agreement. 
Violators may be p rosecuted.  
 
 
 DARS 939:20 23 
© ARSO 20 23 — All rights reserved  v  
Introduction  
 
With the rapid rise of the industrial food animal production system, an increasing number of food 
animals once raised on pastures are now raised in feedlots. Feedlot -raised animals are kept indoors 
for the majority of the year, and they are given feed formulated to speed their growth to market weight 
and supply them with essential nutrients, while minimizing costs to operators. Concerns have arisen 
about the content of these feeds, however, as grain -based diets can produce serious and sometimes 
fatal digestive tract problems in food animals such as cows, goats, and sheep whose stomachs are 
best suited to digesting high -cellulose containing plants like grass.  In addition, recent studies have 
shown that chemical additives in feed may accumulate in animal tissues, potentially exposing 
consumers to unwanted chemicals such as veterinary drug residues and heavy metals.  It is important 
to consider how livestock feed affects animal health, and by extension the health of people who 
consume these animal products.  
 
 DARS 939:20 23(E) 
© ARSO 20 23 — All rights reserved  1  
Feed maize  — Specification  
 
 
1 Scope  
 
This Draft African Standard specif y the requirements , sampling and methods of tests for maize grain  
of varieties grown from common maize  grains  (Zea mays ) intended for the preparation of animal 
feeds . It does not apply to maize intended for human consumption.  
 
2 Normative references  
 
The following documents are referred to in the text in such a way that some or all of their content 
constitutes require ments of this document. For dated references, only the edition cited applies. For 
undated references, the latest edition of the referenced document (including any amendments) 
applies.  
 
 
ARS 56, Prepackaged foods — Labelling  
 
CODEX STAN 193, Codex general standard for contaminants and toxins in food and feed  
 
ISO 605 , Pulses — Determination of impurities, size, foreign odours, insects, and species and variety 
— Test methods  
 
ISO 711, Cereals and cereal products — Determination of moisture content (Basic reference method)  
 
ISO 712 , Cereals and cereal products — Determination of moisture content — Routine reference 
method  
 
ISO 16050,  Foodstuffs — Determination of aflatoxin B 1, and the total content of aflatoxin B 1, B2, G 1 
and G 2 in cereals, nuts and derived products  — High performance liquid chromatographic method  
 
ISO 24333, Cereals and cereal products — Sampling  
 
AOAC Official Method 2001.04, Determination of Fumonisins B 1 and B 2 in corn and corn flakes — 
Liquid chromatography with immunoaffinity column cleanup  
 
 
3 Terms and d efinitions  
 
For the purposes of this document, the following terms and definitions apply.  
 
3.1  
bulk density  
test weight  
cereals ratio of the mass of a cereal to the volume it occupies after being poured into a 
container under well -defined conditions  
 
Note 1 to entry: Bulk density is expressed in kilograms per hectolitre of grains as received. Other units such as grams per litre 
or pound per bushel could also be used .  
 
3.2  
impurity  
all matters of a sample of grain other than the basic cereal of unimpaired quality  
 
Note 1 to entry: In maize, impurities comprise four main categories: broken grain , damaged grains, other grain s and 
miscellaneous impurities  AFRICAN STANDARD  DARS 939:20 23(E) 
2 © ARSO 20 23 — All rights reserved   
3.3  
broken grain  
grain or pieces of grain that can pass through a sieve with a circular mesh of 4,5 mm in diameter  
 
3.4  
damaged grain  
whole kernel that is distinctly discoloured, sprouted, diseased or damaged by weather, pest, heat, or any 
other causes and that is not an unsound grain but that is still fit for human and/or animal consumption  
 
3.4.1  
heat-damaged grain  
grain with a chestnut to black coloration, resulting from the effect of heat, and of which a section of the 
endosperm is yellowish -grey or brownish black resulting from the effect of spontaneous heat generation 
or too extreme heating during drying  
 
3.4.2  
sprouted grain  
grain in which the radicle or plumule is clearly visible to the naked eye  
 
Note 1 to entry: Account should be taken of the general appearance of the sample when its content of sprouted grains is asses sed.  
 
Note 2 to entry: Sprouted grains are those where the germ has undergone clearly visible changes which makes it easy to 
distinguish the sprouted grain from the normal grain.  
 
3.4.3  
grain attacked by pests  
grain that shows visible damage owing to attack by insects, rodents, mites or other pests  
 
3.5 
other grain  
grain other than maize, in any condition  
 
3.6  
miscellaneous impurity  
element that can consist of extraneous seeds , unsound grains , extraneous matter , and impurities of 
animal origin  
 
3.6.1  
extraneous seed  
seed of a plant, whether or not cultivated, other than cereal  
 
Note 1 to entry: “ Noxious seeds” means seeds that are toxic to humans and animals, seeds hampering or complicating the 
cleaning and milling of cereals and seeds affecting the quality of products processed from cereals.  
 
3.6.2  
unsound grain  
grain rendered unfit for human and/or animal consumption, owing to putrefaction, mildew, grain affected 
with fusariosis, or bacterial or other causes  
 
Note 1 to entry: Unsound grains also include grains damaged by spontaneous heat generation or too extreme heating during 
drying which are fully grown grains in which the tegument is coloured greyish -brown to black while the cross -section of the kernel is 
coloured -yellowish grey to brownish -black. 
 
 
3.6.3  
extraneous matter  
matter in a sample that can pass through a sieve with apertures of 1,0 mm and that also includes 
stones, sand, fragments of straw, cob and similar impurities in  a sample that are retained by a sieve with 
apertures of 1,0 mm  
 
3.6.4  DARS 939:20 23(E) 
© ARSO 20 23 — All rights reserved  3 impurity of animal origin  
matter of animal origin (eggs, larvae, nymphs or adults of insects and their fragments, rodent hairs and 
their fragments, mites and their fragments) separated from the product under specified conditions  
 
3.7 
stained kernels  
kernels whose natural colour has been altered by external factors. This includes ground, soil or weather 
damaged kernels, which may have dark stains or discolourations with a rough external appearance  
  
3.8 
diseased grains  
grains made unsafe for human consumption due to decay, moulding, or bacterial decomposition, or 
other causes that may be noticed without having to cut the grains to examine them  
 
3.9 
discoloured kernels  
kernels materially discoloured by excessive heat, including that caused by excessive respiration (heat 
damage) and dried damaged kernels. Kernels may appear darkened, wrinkled, blistered, puffed or 
swollen, often with discoloured, damaged germs. The seed coat may be peeling or may have peeled off 
completely, giving kernels a checked appearance.  
 
3.10 
mouldy kernels  
maize grains with visible mycelial growth on its tip or surface  
  
3.11 
foreign matter  
all organic and inorganic material (such as sand, soil  and glass) other than maize, broken kernels and 
other grains  
 
 
4 Quality requirements  
 
4.1 General requirements  
 
4.1.1  Maize shall be free from foreign odours, moulds, live pests, rat droppings, toxic or noxious 
weed seeds and other injurious contaminants as determined from samples representative of the lot.  
 
4.1.2  Maize shall be  whole and clean . 
 
4.1.3  Maize may be presented as yellow, white, red, or a mixture of these colours.  
 
4.2 Specific requirements  
 
Feed maize  grain  shall be grad ed on the basis of the maximum  limits established in table 1 when 
tested according to the test methods specified therein  
 
Table 1 — Maximum specific requirements for feed maize grains  
 
 
5. Contaminants  
 S/N Characteristics  Maximum Limits  Test methods  
Grade 1  Grade 2  Grade 3   
(1) Moisture, % m/m  14 14 14 ISO 711 ,712  
(2) Broken kernels, % m/m   6 8 10  
ISO 605  (3) Damaged grain,  % m/m  10 10 10 
(4) Miscellaneous impurities,  % m/m  2 2 2 
(5) Total content of the impurities,  % m/m  15 15 15 DARS 939:20 23(E) 
4 © ARSO 20 23 — All rights reserved  5.1 Heavy metals  
 
Feed m aize grains shall comply with those maximum limits for metal contaminants specified in 
CODEX STAN 193 and in particular those listed in Table 2 . 
 
Table 2  Heavy Metal limits    
 
S/N Heavy metals  Maximum limits  
ppm  Test method s 
(1) Arsenic (As)  2,0 ISO 27085  
(2) Mercury (Hg)  0,5 ISO 6637  
(3) Lead (Pb)  1,0 ISO 6633  
(4) Cadmium (Cd)  5,0 ISO 6561 -1 or ISO 6561 -2 
 
 
5.2 Pesticide residues  
 
Maize grains shall comply with those maximum pesticide residue limits established by the Codex 
Alimentarius Commission for this commodity . 
 
5.3 Aflatoxin  
 
Maize grains for animal feeds shall comply with those maximum limits for aflatoxins specified in 
CODEX STAN 193 and in particular those listed in Table 3.  
 
Table 3 — Aflatoxin limits  for feed maize  
S/N Aflatoxin  Maximum limits  
 ppb Test method s 
(1) Total aflatoxin  20 ISO 16050  
(2) Aflatoxin B1   10  ISO 17034  
 
 
6 Hygiene  
 
Feed maize shall be processed and  handled in accordance with CAC 54.  
 
 
 
 
7 Packaging and Labelling  
 
7.1 Packaging  
 
The feed maize  shall be pack aged in new and clean food grade packaging material or de livered in 
bulk containers. The  packaging material shall be  properly  sealed . In the case of bulk deliveries, the 
delivery outlet of the bulk tanker shall be sealed after loading.  
 
7.2   Labelling  
 
In addition to the requirements of ARS 56, the following specific labelling requirements shall apply and 
shall be legibly and indelibly marked:  
 
(a) Name , colour, variety and grade  of the feed maize  
(b) Name and address or contact information o f producer ; DARS 939:20 23(E) 
© ARSO 20 23 — All rights reserved  5 (c) Net weight when packed, in SI units : 
(d) Lot/Batch  /Code number;  
(e) Crop year  
(f) Country of origin ; and  
(g) Directions for use and storage conditions  
 
 
8. Sampling  
 
Sampling shall be done in accordance with the ISO 24333 . 
 DARS 939:20 23(E) 
6 © ARSO 20 23 — All rights reserved   
Bibliography  
. 
Cereals Grading and Marking Rules, 2001 , Ministry of Agriculture, Government of India, Schedule V, 
Grade Designation and Definition of Quality of Maize  
 
CODEX STAN 153:1985 (Rev.1:1995), Standard for Maize (Corn)  
 
Corn,  Official Grain Grading Guide, August 1, 2012, Canadian Grain Commission  
 
United States Standards for Corn , Effective September 1996  
 
CODEX STAN 193:1995 (Rev.5:2009), General standard for contaminants and toxins in foods  
 
CODEX STAN 228:2001 (Rev.1:2004), General methods of analysis for contaminants  
 
 DARS 939:2013(E)  
© ARSO 20 23 — All rights reserved