One of the targets often quoted as a measure of the fertility of a suckler herd is that there should be 0.95 calves weaned per female put to the bull (stock bull or AI) in the previous year.

It is a target promoted by various advisory bodies across these islands including the Better Returns Programme in England, Teagasc in the Republic of Ireland, CAFRE in NI and Quality Meat Scotland (QMS). They all correctly point out that it is a key driver of profitability in suckler production.

But how realistic a target is it? On the face of it, most suckler producers would probably suggest that it is achievable, and certainly if you calved down 100 cows this spring, you would hope to have upwards of 95 live calves on the ground.

However, the number of females to the bull is the number of calved cows and heifers put out in the spring in the hope that they become pregnant and calve the following year. It is not the average number of cows in the herd, which is a different figure entirely. That figure does not include heifers that turn out not-in-calf. It is also a figure that can be manipulated downwards by culling out cows that are not pregnant after breeding. In Ireland, north and south, the average number of calves weaned per cow per year is 0.82 to 0.83. The number of calves weaned per female put to the bull is probably significantly less again.

It should also be recognised that both figures can be improved by leaving the bull with the cows all year round. Most will eventually get pregnant, but if the calving interval (the number of days from one calving to the next) is extended, it is a false economy. The average calving interval in a herd should be close to 365 days. In NI, the average is just over 400 days, while for the Republic of Ireland it is 407 days. In other words, on average a suckler cow in Ireland which calved on 15 March 2016 will not calve again until 26 April 2017.

However, the calving interval figure can also be manipulated down by culling out all late-calving cows. It is possible to have an excellent figure for calving interval, yet have inherently poor fertility on the farm. Therefore, when assessing fertility performance, it is important to look at both calves reared per cow to the bull and calving interval.

Aim

For farmers in the NI suckler beef programme, the aim is to keep a tight breeding period of around 12 to 14 weeks, so that the calving interval is maintained at 365 to 370 days. That inevitably means that some cows and heifers put to the bull do not turn out in-calf and have to be culled each year.

Each farmer in the programme is asked to keep accurate records of performance at breeding. They also record reasons for culling and all problems around calving. Table 1 shows a summary of performance in their herds calving this spring. The information is based on a total of 713 female animals put to the bull in 2015. The result is 637 calves alive on 1 July 2016, which works out at 0.84 calves per female to the bull, well short of the target of 0.95.

This suggests that either the performance on the farms must be improved, or the target of 0.95 is unrealistic for the majority of farmers. There is always room for improvement on any farm, and in a couple of farms in particular, there needs to be more emphasis put on managing newborn calves.

However, farm industry advisers must also consider whether the targets they set are actually achievable in practice and if the measures they use are giving farmers false reassurance rather than hard facts. Anyone consistently achieving more than 0.85 calves reared per female to the bull alongside a calving interval of less than 370 days is doing an excellent job on fertility. Where performance falls short, this should be discussed with the farm vet or farm adviser to see where improvements could be made.

Replacements

The other simple take-home message is that if any suckler producer is going to maintain a tight calving interval, as well as a closed herd, they must have sufficient numbers of replacements coming through each year. In fact, the experience of farms on the programme is that all bulls that they use must have the potential to be used to breed replacements. There is little room on the farms for bulls bought purely on the basis of terminal sire traits.

As shown in Table 1, across the farms on the suckler beef programme each farmer put an average of 71 cows and heifers out to bulls (or used AI) last summer, and at 1 July 2016 they had an average of just under 60 living calves on the ground in their spring-calving herds.

As expected, there is a significant range in the figures and slightly better success calving mature cows than heifers. Only one farm got close to the industry target and had an exceptional year, ending up with 61 living calves after putting 65 cows and heifers to the bull in 2015 (an average of 0.94 calves per female to the bull). The figures on this farm were helped significantly by a number of sets of living twin calves. Most of the other farms achieved results in the low 0.80s, with one farm down at 0.73 after having a number of disease problems last winter.

Looking in more detail at the reasons why the farms were below target, out of the 713 female animals that went to the bull, 48 did not go in-calf (6.7%) after the breeding period and were culled. Another 10 either turned out not in-calf or died pre-calving, with a further three cows dead at calving time.

A total of 52 calves were lost at or shortly after calving (7.5%), either the result of difficult calvings, or disease issues such as scour and pneumonia, while across both cows and heifers, a total of 17 aborted calves early (2.5%). This is in line with what is seen as a normal level of abortion in pregnant cattle of 2% to 3%.

There are a number of sets of twin calves to bring the figures back up to 596 living calves at 1 July. A target often quoted for suckler herds is to have a replacement rate of 15% – ie.15 heifers coming in and replacing 15 culls in a 100-cow herd each year.

Looking in detail at the figures on the programme farms would suggest that this replacement rate is too low if numbers are to be retained. On average, 23% of breeding animals calving down in programme herds this spring were first-calving heifers.

Across the majority of programme farms, all problem animals are quickly removed out of the system – there is no room for passenger animals and a strong emphasis on bringing replacement heifers through. For those that doubt the management decisions, remember that a number of these farms are right at the top of CAFRE benchmarking results in terms of margins produced per hectare.