Elizabeth Doughman, editor, WATT PoultryUSA and Poultry Future: Hello and welcome to WATT Poultry Chat. I'm Elizabeth Doughman, the editor of WATT PoultryUSA and Poultry Future.
This Watt Poultry Chat is brought to you by Jones Hamilton. Jones-Hamilton manufactures products that lower pH – empowering producers to maintain healthier house environments that support better performance. They’ve lead the industry for 30 years – starting with the leading litter amendment, PLT, to the new pest control solution for organic poultry production, DiaMate.
Joining us today is Dr. Craig Coufal, senior research and technical services manager at Jones-Hamilton.
Thanks for joining us, Craig.
We often talk about ammonia as an air-quality issue, but it’s really a bird health issue. Can you explain why ammonia becomes more challenging later in the flock and what prolonged exposure actually does to bird health and overall performance?
Dr. Craig Coufal, senior research and technical services manager, Jones-Hamilton: Here in the U.S., we typically recycle litter for many flocks.
Obviously, ammonia is a big challenge at the time of chick placement when we have this older used litter and litter amendments are typically added to reduce that ammonia challenge. That's been done for 25 years, and no one really even thinks twice about it anymore. It's just standard practice.
But litter amendments applied prior to chick placement only lasts for so long, right? And then the ammonia buffers out the acid that's been added and basically neutralizes that acid. And so, as the flock ages, ammonia production is still occurring.
Typically, we don't worry about it too much later in the flock because we increase ventilation rates and we pull that ammonia out of the house. But it still can be a challenge to the birds, because the birds are sitting right there on the litter and as that ammonia is coming on the litter, they're still exposed to it, even though it's then quickly ventilated.
They're still exposed to that ammonia and ammonia damages the respiratory system. It damages the cilia of the trachea that filters out particles and bacteria. As the birds age and the initial litter amendment is used up, we still have this ammonia challenge that the birds are exposed to on a daily basis. This could even be much worse in wintertime when it's very cold outside and ventilation rates are even lower, even towards the end of a flock.
That's when we really see these challenges. I's really an overall bird health issue because of that damage that the ammonia does to that respiratory system that allows for other bacteria and dust and things to actually filter deeper into the respiratory system of the bird, thus leading to potential bacterial infections like air sacculitis and other types of health issues.
Doughman: You talked about the link between ammonia and pH, but how else does litter pH affect bacterial activity in the house, and how does that change over the growout?
Coufal: Great question. When we first put those litter amendments down on day one, we're going to drop that pH very low. Typically, most bacteria, particularly pathogenic bacteria that might affect the bird, don't grow well below a pH of four.
If we get that pH low at the beginning, we've got a nice healthy litter bed. Those birds get off to a good start. We don't have a lot of bacterial exposure to those birds if we do that. But again, as the flock ages that pH is going to start to come up because the acid is being buffered out, which then allows those bacteria to grow again.
Typically, if we look at bacterial counts in litter, it'll be very low at the beginning when chicks replaced. But then as the flock ages, the bacterial activity in that litter is going to increase.
One, because the pH is coming back up from that initial litter amendment application, but also because we're adding more moisture as the birds deposit more manure. Manure is 70% water typically. When you have a high moisture environment, a moderate to high pH environment, bacteria are going to thrive. The more bacteria that are thriving and reproducing and accumulating in that litter, the more potential bacterial challenge we have to those birds as they age.
Doughman: A lot of management decisions come down to timing. What role does timing play in litter pH manipulation and how can that impact disease pressure, livability and performance?
Coufal: If we apply that litter amendment at the beginning, we're going to create that healthier bed. The chicks get off to a good start. And then, that pH comes up, the bacteria start to proliferate as I talked about.
If there's any other disease challenges or environmental stressors that come along that really allows those bacteria to potentially impact the bird. If the bird has a really good solid immune system, it can typically defend and fight off those bacteria that may be growing in the litter, but in times of stress – maybe we have a viral challenge such as avian metapneumovirus or bronchitis, or maybe we have some other gut health stressors or things that come along – now all those bacteria in the litter could potentially impact the overall health of those birds.
That's when you run into issues of immune suppression and you really start to see more mortality, morbidity in those birds, which of course is going reduce performance.
If we can manipulate that litter pH – hold that litter pH below four – to reduce that bacterial load in that litter, that's going to prevent that secondary bacterial challenge to those birds.
For example, when you have a viral challenge that comes in such as avian metapneumovirus, a lot of times people have noted that it's not really the virus that kills or hurts the chickens as much as it is the secondary bacterial infections. If we can decrease the bacterial load in that environment by holding the pH down – and of course that's going to take subsequent litter amendment, more acid to do that – we can then see a reduced impact to the birds as they get through that viral challenge.
We're not saying that by applying a litter amendment or by acidifying the litter, we're going to stop a viral infection or we're going to prevent it. But what we'll do is we will reduce the severity of the impacts through production because we've reduced the secondary bacterial challenges to those birds during that viral challenge.
Doughman: Thank you so much for sharing these insights. For more information on the solutions discussed here today, visit Jones Hamilton at joneshamiltonag.com.
Thanks again, Craig, and thanks to you for tuning in.
