Late-calving cows putting suckler herd profits at risk, CAFRE warns

Farmers allowing calving seasons to drift over long periods are quietly losing efficiency, calf weight and profitability, according to a new warning from CAFRE beef and sheep adviser Jack Friar.

The College of Agriculture, Food and Rural Enterprise says maintaining a compact calving pattern remains one of the clearest indicators of reproductive performance in suckler herds — with late-calving cows creating a knock-on effect that can become increasingly difficult to reverse.

Mr Friar said herds with extended calving periods often reveal deeper weaknesses in breeding management, conception rates or cow recovery after calving, while tighter systems consistently produce stronger performance and more uniform calves.

“A tight calving spread is a strong indicator of good herd fertility,” he explained.

“Where calving is spread over a long period it usually points to underlying weaknesses in breeding management, submission rate, conception rate or cow recovery after calving.”

Early calving delivers heavier calves and easier herd management

Jack Friar, CAFRE, Beef and Sheep Adviser.

CAFRE advises that ideally between 80 and 90 per cent of cows should calve within the first six weeks of the calving season.

Cows calving earlier in the season have more time to recover before breeding begins again, while late-calving cows often continue slipping further behind year after year.

The consequences are not just reproductive. Early-born calves benefit from a significantly longer growing period before weaning, with calves born in the first six weeks often weighing between 20kg and 30kg more at weaning than later-born animals simply because they have had more days to grow.

CAFRE says a compact calving spread also creates:

• More uniform calf age and weight at weaning

• Easier health planning and vaccination programmes

• Improved labour efficiency during calving

• Simpler dosing and herd management

• A more even batch of calves for sale or retention

Mr Friar warned that allowing breeding seasons to drift too long can quickly undermine herd fertility targets.

“In most suckler herds the breeding season should ideally be limited to nine to 12 weeks,” he said.

“If breeding is allowed to drift on for too long, late conceptions become late calvings, and those cows often slip later again the following year.”

Heat detection and conception rates under scrutiny

CAFRE says one of the earliest warning signs of problems is poor submission rates during the breeding season.

If too many cows are not cycling or are not being served early, the calving spread widens rapidly. Causes can include inadequate body condition, poor recovery after calving, weak heat detection or cows simply being missed during observation.

Accurate heat detection remains critical, particularly in herds using artificial insemination (AI). Farmers are being encouraged to watch for mounting behaviour, restlessness, standing to be mounted and increased activity during breeding periods.

CAFRE also highlighted the use of heat detection aids including:

• Tail paint

• Chin-ball harnesses

• Teaser bulls

• Activity monitors

“These tools can improve the accuracy of heat detection and help ensure cows are served early in the breeding period,” Mr Friar said.

Conception rate remains another major driver of calving spread.

CAFRE says first-service conception rates of between 60 and 70 per cent are achievable in well-managed suckler herds, but poor conception performance can rapidly extend breeding seasons as cows repeatedly return to heat and are served later.

“When conception rate falls, attention should be given to bull fertility, service timing, cow health, nutrition and heat detection accuracy,” Mr Friar said.

“There is little value in identifying heats accurately if cows are then being served at the wrong time or by a sub-fertile bull.”

Bull fitness and herd records seen as critical

Bull management was also identified as central to maintaining tighter calving patterns.

CAFRE says breeding bulls should be fertile, physically sound and fit before breeding begins, with particular attention paid to feet and leg health. Lame or unfit bulls may fail to serve cows effectively, creating unseen fertility problems across the herd.

Farmers using natural service systems are also advised to closely observe bull activity during the early stages of breeding to ensure cows are being served normally.

Late-calving cows require especially close management, according to CAFRE, as they have less recovery time before the next breeding cycle begins.

“In some cases, repeatedly late-calving cows may need to be culled if they are consistently failing to maintain the herd pattern,” Mr Friar warned.

“Carrying too many regularly late cows can make it very difficult to tighten the calving season.”

CAFRE stressed that accurate record keeping is essential if farmers are to properly monitor fertility performance.

Recording calving dates, breeding dates, service dates and pregnancy outcomes allows farmers to identify cows repeatedly calving late, poor conception performance and wider breeding problems before they become embedded in the herd.

Pregnancy scanning helps identify costly empty cows early

Pregnancy scanning carried out around 30 to 50 days after the breeding season ends can also provide an early picture of conception spread and identify barren cows before winter feed costs accumulate.

CAFRE says well-managed herds should ideally keep barren cow levels below five per cent.

“Empty cows reduce overall herd efficiency and consume feed without producing a calf,” Mr Friar said.

The adviser concluded that compact calving systems do not happen accidentally and require deliberate management decisions throughout the year.

“By controlling the breeding season, monitoring submission and conception rate, using accurate heat detection, scanning cows and taking action on late-calving animals, farmers can maintain a compact calving pattern and improve overall herd performance.”

Farmers seeking further advice are encouraged to contact their local CAFRE Beef and Sheep Adviser through their local DAERA Direct Office.