AFBI suckler beef research at a crossroads

A 100-cow suckler herd was first established at the Agri-Food and Biosciences Institute (AFBI) about 10 years ago. Among the aims at the time was to undertake research on the newly emerging Stabiliser breed, and compare these animals with Limousin crosses from the dairy herd.

Some of the results are to be expected, although other findings are probably not to the liking of those selling Stabiliser bulls. Whether AFBI should ever have got into comparing two breeds of suckler cows is perhaps debatable.

But we all must recognise that independent research is the cornerstone of a successful farming industry. While different breed societies can make various claims about the merits of their breed over others, if it isn’t backed up with independent science-based research, the marketing literature is of little value.

So what have AFBI found over the last 10 years? Basically that Limousin-cross Holstein Friesians have more milk than Stabilisers (no surprise there) so produce heavier calves at weaning. By the time the animals are slaughtered, the Stabiliser-bred animals have generally caught up.

Body condition

On the same feeding regime, the Stabiliser cows will generally have a higher body condition score. So in a dry period, they require less supplementary feed, and costs can be taken out.

But perhaps unexpected is the weight of the mature Stabiliser cows compared with the Lim crosses. At the same body condition score of three, the Stabilisers are averaging around 650kg, which is similar to, and even slightly ahead of the Lim crosses. In recent years, AFBI has been trying to breed replacements using Stabiliser bulls that will take some of that size out – with the aim of having a 600kg cow when in condition score three.

Longevity

However, one area where the Stabiliser (and any other beef-bred crosses) will come into their own, when compared with a Lim-cross Holstein Friesian, is cow longevity.

The dairy influence will bring more milk, but also all those unwanted traits of lower fertility, bad legs and feet, and pendulous udders. To quantify the effect fully takes a long time, probably more than 10 years.

So what next for the suckler herd at AFBI? It is grazed at AFBI Hillsborough, but a lack of suitable cow accommodation at the Co Down site means it is housed at AFBI Loughgall. It is far from an ideal scenario, given the risk of movement restrictions due to TB.

A few years ago the herd remained housed all summer at Loughgall as a result of a TB outbreak.

Abbey Farm

Longer-term, it has been proposed that the herd would move permanently to the Abbey Farm at Greenmount, with all progeny from this herd and Greenmount’s other suckler herds going to a new facility at AFBI Hillsborough, and to be used in finishing trials.

In essence, it would bring an end to intensive suckler cow research, but the reality is that it is limited in what can be achieved with a 100-cow herd. In recent years, the trend has been to undertake studies on-farm, using farmer co-researchers, which gives AFBI scientists access to robust data from a much greater number of suckler cows.

Over the last 12 months, it has become clear that ammonia emissions from livestock is a major threat to future growth of the farming industry in NI. The issue has also shot up the agenda at AFBI.

“We are planning a large programme of work on ammonia, hopefully to reduce ammonia emissions from livestock farms, and make these farms more sustainable going forward,” said AFBI director Dr Elizabeth Magowan in her welcoming remarks at the start of the farm tour at AFBI Loughgall.

Floor systems

Part of that work will consider flooring systems, as well as diet changes, on ammonia emissions, with the aim of getting the “right data in the right models, to get the right answers”, she said.

Aside from ammonia, other research work will continue to focus on improved technical efficiency, particularly increasing production and utilisation of grass.

A study is also ongoing, in association with AgriSearch and the Agriculture and Horticulture Development Board (AHDB) in England, to update beef nutrition models. The current models are based on equations developed over 30 years ago, which are thought to be underestimating the nutrient requirements (ME and protein) of modern beef cattle.

Body condition link to calf growth

Traditional practice has been to allow suckler cows to gain weight and condition over the summer, housing cattle at a body condition score (BCS) of 3.0. There is then the opportunity to take out some feed cost by allowing condition to slip to around 2.5 at calving in the spring.

However, recent research at AFBI has indicated that cows in too much condition in mid-pregnancy (around housing time) has a negative impact on subsequent calf performance.

“The calf will grow slower – it has been programmed to do less. We see a similar effect in sheep,” explained Dr Raymond Steen, the former head of beef research at Hillsborough.

In the ewe, where it is in a BCS of around three at tupping time, it can be allowed to lose around 0.5 of a condition score in mid-pregnancy. It is thought that this stimulates the placenta to develop to its maximum potential. However, if animals are overfed in mid-pregnancy it can lead to abnormal partitioning of nutrients to maternal tissues, and the birth of under-sized lambs of low viability.

25% of heifers calving at three years

An analysis of information held on the Bovine Information System (BovIS) shows that the average age of first calving for the main suckler beef breeds is 30 months.

The average is consistent across all the breeds, with no significant difference between early maturing animals such as Angus and Hereford, or continental cattle such as Limousin, Simmental or Charolais.

The data shows that nearly 25% of first-calving beef heifers are actually 36 months old and above.

According to Frances Titterington from AFBI, the 30-month average has not changed in 20 years, despite all the advisory messages about the financial benefit of calving at 24 months.

“It is well documented that heifers that calve at 24 months will produce more calves in their lifetime,” Titterington pointed out.

To successfully calve at 24 months, performance at grass is key.

Heifers should be 60% of mature cow weight at 14 months (around 390kg if mature weight is assumed to be 650kg), and 90% of mature weight at calving (585kg).

To ensure heifers are growing to target, an online growth monitoring tool is available through BovIS online.

Benefit from rubber on slats

Three studies on different floor types have been conducted at AFBI using Holstein Friesian bulls.

The different floor types compared include concrete slats, and concrete slats covered with rubber.

Presenting the results of the studies, Dr Steven Morrison from AFBI said that while differences in performance have been variable, there is a trend showing a benefit from finishing cattle on rubber.

Significant

In one of the studies, the difference between the floor types was statistically significant.

The data collected also showed that cattle on rubber floors spent more time lying, and were able to get up and down more freely. “It may reflect more natural behaviour,” said Morrison.

Potential role for sorted semen on suckler farms

Using sorted (sexed) semen could have a number of potential advantages on a suckler farm.

Where heifer semen is used in first-calving heifers, it should result in less problems at calving. In cows, using sorted semen could either increase the number of replacements available for breeding, or increase the number of bull calves born for beef production.

However, there are some drawbacks, including limited bull availability and higher semen costs.

Results from studies presented by Dr Francis Lively from AFBI also suggest that conception rates to first service will be lower than with conventional semen. Around 90% of calves born to sorted semen in the studies were the expected sex.

Synchronisation and AI on trial in sucklers