What’s the cost of ammonia in your calf shed?

Ammonia is a typically overlooked performance thief in calf sheds – quietly and consistently chipping away at calf health, growth rates, and feed efficiency.

It starts with a simple reaction inside the calf shed. Calves urinate, excreting urea. Bacteria present in manure and bedding break that urea down into ammonia gas and carbon dioxide. Add moisture and warmth into the mix and the process accelerates rapidly. 

In practical terms: Urine + manure + bacteria + moisture = rising ammonia levels + increasing litter pH.

Wet bedding, poor ventilation, and high stocking densities exacerbates the issue, but even in well maintained sheds with good ventilation, ammonia can quickly accumulate. In humid sheds, ammonia tends to sit low, concentrating at calf nose height rather than at human breathing height, often remaining undetected by calf rearers.
 

Ammonia is highly irritating to the calves’ respiratory tract 

Even when the animals do not appear clinically sick, ammonia exposure damages the delicate lining of the airways and weakens the calf’s first line of defence against respiratory disease. Once the immune system is activated, nutrients that should be driving calf growth are diverted into repair and defence instead.
 

Measure ammonia levels in the calf shed with an ammonia meter

New Zealand’s Code of Welfare for Dairy Cattle requires immediate action if ammonia levels at animal height reach 25ppm, while recommended best practice is to keep levels below 15ppm. But emerging research suggests even those levels may still be too high for young calves. In a large Belgian study involving more than 428 group-housed calves across 60 farms, researchers found that prolonged exposure to ammonia concentrations as low as 4ppm increased the risk of pneumonia.

Notably 4ppm is below the level most humans can even smell. On top of that, regular exposure to ammonia causes “olfactory fatigue”, meaning the longer people spend in the shed, the harder it becomes to detect. In other words, just because a calf shed does not smell strongly of ammonia does not mean calves are not being affected.

High bedding pH is an unseen contributing factor

Ammonia forms more readily under alkaline conditions, which means the higher the bedding pH, the more ammonia is released into the air. This is why alkaline products such as lime, zeolite and hydrated lime, or products which include these minerals as a base, will worsen the problem. While these products may appear to dry bedding, they also increase alkalinity - promoting ammonia volatilisation and creating a harsher environment for calves’ skin and lungs. 
 

How to manage ammonia

Managing ammonia starts with three key principles: keeping bedding dry, maintaining good airflow, and controlling pH. Fresh, dry bedding and effective ventilation will reduce moisture levels and slow ammonia production. However, a low pH bedding conditioner such as Stalosan F will make the real difference.

A powerful drying agent, Stalosan F binds both moisture and ammonia while lowering and stabilising bedding pH. With a pH of less than 4, Stalosan F helps create a more neutral bedding environment, far less favourable for ammonia release and pathogen survival. In a low pH environment, with low ammonia concentration, more of the energy calves consume will go into growth instead of immune stress and recovery.

For more information on managing ammonia in calf sheds, visit Stock IQ or talk to your local Farm Source team.
 

Article supplied by Stock IQ