By: Iman Hernaman*

Adulteration of feed ingredients by mixing limestone into rice bran will reduce nutrient content and negatively impact livestock performance.

Rice bran is a by-product of the rice milling process derived from the outer layer of dehulled rice. Rice milling typically produces about 65% milled rice and 35% milling by-products, consisting of husk (23%), bran and fine bran (10%), with the remaining percentage made up of impurities. Rice bran is the by-product generated during the first milling process, while fine bran (bekatul) is produced during the second milling process.

This feed ingredient is widely used in animal feed. The inclusion level of rice bran in pig diets is relatively high, reaching 30–40% of the ration. In poultry diets, its use is more limited, namely 0–15% for layer starter phase, and 0–20% for grower and layer phases. For broilers, inclusion levels generally range from 5–20%, and should not exceed 20% as it may reduce productivity. Meanwhile, rice bran is used quite extensively in duck feed, accounting for around 25–30% of the total feed composition. Thus, rice bran is widely utilized as a feed ingredient for both poultry and pigs.

The availability of rice bran is fluctuating, which affects its market price. High demand for rice bran that is not matched by increased production often leads to price spikes, creating opportunities for adulteration practices by mixing rice bran with other substances. Such practices are generally carried out to increase profit margins by unscrupulous suppliers or feed traders. Rice bran that has been mixed with other substances experiences a reduction in nutrient content in animal rations and can negatively affect livestock performance. Recently, reports and discussions with feed industry practitioners have indicated cases where rice bran has been heavily mixed with limestone, commonly known as stone meal (limestone).

Feed Ingredient Adulteration

Feed adulteration is the practice of substituting or mixing original feed ingredients with other materials that have no nutritional value or possess different nutrient compositions. This is done to increase feed volume, reduce production costs, or purely for financial gain.

Feed adulteration can be carried out in several ways, including:

1. The addition of inferior materials that have no nutritional value, such as rice husks, fine bran dust, or soil, into feed;

2. The use of other materials that have physical characteristics similar to the original feed ingredient but possess different nutritional content;

3. Processing or mixing genuine feed ingredients in such a way that their nutrient content is reduced, for example by adding substances that inhibit nutrient absorption.

Feed adulteration can have negative impacts on livestock, such as:

1. Indigestible or inferior materials may cause digestive disorders, including diarrhea or constipation;

2. If adulterated feed contains insufficient or incomplete nutrients, livestock may suffer from nutrient deficiencies, affecting growth and health;

3. Adulterated feed reduces feed efficiency, resulting in suboptimal animal growth, which ultimately affects production performance and farmers’ profitability.

This article is an excerpt from the Research section of Poultry Indonesia magazine, September 2025 edition. Read the full article in Poultry Indonesia Magazine September 2025 Edition. For subscriptions or further information, please contact: https://wa.me/+6287780120754 or sirkulasipoultry@gmail.com