One of the cleaner ways to evaluate the effect of beneficial microorganisms in a livestock operation is a controlled study with consistent animal numbers, uniform conditions, and measured outcomes over time. A 2021 study published in the International Journal of Food Science (Hindawi/Wiley) did exactly that for laying hens — and the results provide a useful data point for poultry producers exploring biological water supplementation.
The study, conducted by Atsbeha and colleagues and available through PubMed Central (PMC8279862), used 180 ISA Brown pullets of uniform age and weight in a cage housing system. The birds were divided into four treatment groups with three replications each, for 15 hens per replicate unit. One treatment group received EM (effective microorganisms) in both feed and drinking water; others received EM in feed or water only, or served as untreated controls. The study ran across multiple laying periods to capture both early and peak production data.
Key outcomes from the group receiving EM in both feed and water:
- Egg laying percentage at peak production: 92.8% — significantly higher than control groups
- Egg weight: 6% heavier than eggs from control birds — a meaningful quality difference in commercial egg production
- Feed conversion rate: 2.05 — lower than controls, indicating improved efficiency in converting feed to egg mass
- Daily feed intake: 115.5 grams per bird — lower than controls despite better production outcomes
- Additional net profit: at least 40.30 ETB per day per 45 hens — demonstrating a calculable economic advantage in the study’s production context
The study also documented significant improvement in egg quality indicators in the EM-supplemented group, including shell integrity and yolk characteristics, though the specific parameters varied by treatment configuration.
The mechanism behind these results is consistent with how lactic acid bacteria and beneficial yeasts — the primary organisms in most fermented microbial inoculants — are understood to function in monogastric animals. When introduced through drinking water, they colonize sections of the digestive tract, producing short-chain fatty acids and antimicrobial compounds that may support feed digestion, reduce pathogen load in the gut, and improve nutrient assimilation. In laying hens, improved nutrient uptake is directly linked to egg mass and shell quality.
The practical delivery method in this study — adding fermented microbial inoculant to the drinking water supply — is the same approach used in farm-scale operations. A proportional injector or dosatron at the water header can meter the inoculant into the water line continuously, so every bird in the house receives the biology with every drink without requiring individual dosing.
This study doesn’t make definitive claims about all flocks in all environments. But it provides a well-structured reference point for poultry producers who want to understand what outcomes have been observed under controlled conditions when beneficial microorganisms are delivered through the water supply.
Disclaimer: Results from controlled studies may not directly translate to all production environments. Application outcomes vary by bird genetics, housing system, water quality, diet, and management practices. This material is educational and does not replace professional veterinary or production advice.
Source: Atsbeha T, et al. The Impact of Effective Microorganisms (EM) on Egg Quality and Laying Performance of Chickens. International Journal of Food Science. 2021. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8279862/