If you think that Irish dairy grazing is all about idyllic cows on lush green pastures, you’re only partially correct. Dr. Laura Boyle, of Teagasc, a research, advisory and training organization based in Ireland and operated by the Agriculture & Food Development Authority, addressed the welfare of dairy cows in Irish grazing systems in a recent Dairy Cattle Welfare Council (DCWC) webinar.
Dairy cows graze in Ireland, with pasture-based herds grazing between two and seven months of the year, depending on location and climate. These herds are then winter housed.
The Irish dairy industry is seeing a rapid increase in the number of farms with more than 100 cows and a decline in those with less than 40 head, a trend which began about 10 years ago. With that trend, the concern for dairy cow welfare has come to the forefront. Confined herds, which are fed total mixed rations year-round, produce about 20% more volume of milk than grazed herds.
“Our systems are focused on achieving high milk solids per hectare,” Boyle said. And with that focus, along with other industry changes, comes cow welfare concerns.
Cows have been shown to work very hard to gain access to the outdoors, preferring to be on pasture at night, and indoors with TMR access during the day, particularly if it is hot and humid or windy and rainy. Research has shown that cows that have pasture access and are fed TMR produce the most milk. This is due to decreased stress, increased lying time and enhanced cow comfort, Boyle said.
“The best option for cow welfare is to give them free choice,” she said.
Yet bigger herds and a fragmented land base can make grazing less feasible for some producers. A focus on maximizing milk production may cause some dairy farmers to focus on feeding cows rather than allowing them to access pasture. Overcrowding and low-cost housing systems, to accommodate more cows with less economic outlay, such as cement stalls outside, an option used on Irish dairy farms, increases herd health concerns.
Whether pasture based or not, the intensification – pushing for more production on less land – can cause decreased longevity, reduced fertility and more herd health concerns, she said.
Confined cows showed lower expressions of estrus, reduced rates of conception success and more incidences of metritis. Confined cows also had more udder issues, more leg concerns and lameness and more behavioral disorders.
While metabolic problems – grass tetany, negative energy balance and sub-acute ruminal acidosis – were shown to be more concerns in Irish pasture-based systems, there were far fewer reproductive problems or other herd health issues than in confined housing systems. Pasture-based systems have variable feed sources, and even moderate milk production can cause cows to have difficulty consuming and digesting enough forages to meet energy needs. Poor forage digestibility is a concern. Long walks to pasture can cause energy utilization issues. Lame cows won’t eat.
In the Irish pasture system, spring calving herds are the norm. All cows are in the same stages of pregnancy. Because cows maximize milk production four to six weeks postpartum, but maximized grass production doesn’t occur until the cows are about eight to 10 weeks postpartum, there can be challenges with forage availability when it is most needed.
In a 2021-22 study of Irish pasture-based dairy farms, cows were winter housed, on average, for four months. They produced and average of 5.7 gallons of milk/cow/day, and were fed 0.9 tons of concentrate/cow/year. All herds were spring calving and housed over winter in free-stalls.
Cows with lower body condition scores were found on larger farms and in herds run by younger farmers. These farms also tended to be overstocked at the feed face.
Sixty-eight percent of the farms bedded with mats only, while only 4% added straw to the mats. Twenty-eight percent have no bedding system, spreading lime in stalls only. Of these, 12% were bare concrete, and another 4% had less than 0.5 cm of bedding. On the majority of farms, there was less than one cubicle per cow.
Another area of concern was seen with laneways. Lameness increased on farms were no laneway repairs were done each year, which occurred on about one-quarter of the farms. Some of the farms had 30% of the cows lame, which is similar to the rate in year-round confined systems. On average, 10% of cows were lame during the grazing season and the same rate was seen during the winter housing period. Herd size did not impact the rate of lameness seen.
The study also demonstrated that recordkeeping led to less tail or hock injuries and reduced lameness. Silage quality testing and herd level disease screening led to less thin cows.
“Farmers believe their own data” and then make management changes, Boyle said.
Poor management will cause poor welfare outcomes and great management systems can lead to better cow welfare, whether pasture-based or confined, she said. In either system, challenges to cow welfare arise due to many factors facing dairy farming today.
In an era of rising production costs, climate change and labor concerns, concerns for cow welfare are increasing. Overcrowding, less labor to monitor cows or perform daily tasks carefully, a changing climate where rain, drought or temperature extremes impact pasture quality and availability and a push for producing more milk per farm are all detriments to cow welfare. Preventing cow welfare concerns while in a “race to the bottom in an effort to produce cheap foods in an era of rising costs,” Boyle said, is the main challenge facing Irish dairy farming today.
While the Irish pasture-based system is really a hybrid system, with many months confined, options for increasing pasture are possible. More pasture biodiversity, shelter on pasture and a focus on cow and herd health and longevity rather than milk production can all be solutions to enhancing cow welfare and creating a more extensive pastured dairy system.
“I’m not sure of any one single solution, but I think we will need heterogeneity in the systems of milk production” to create a truly sustainable dairy industry, Boyle said. “There are definitely enormous benefits to dairy cow welfare associated with access to pasture.”
by Tamara Scully