Research has shown that shifting feeding of beef cows to later in the day could mean more animals will calve during daylight hours.
Beef herds should be aiming for calf mortality rates of less than 3 per cent from birth to weaning, according to AHDB figures, and with the highest risk period generally considered as being within 24 hours after calving, this is the time when closest supervision is needed.
Several studies have found that feeding cows later in the day could lead to more animals calving during daylight hours in some systems.
The calving pattern of cows in some herds fed in the early evening instead of the morning has been found to shift towards daytime hours, rather than during the night.
Originally observed and reported by Canadian farmer Gus Konefal in the 1970s, subsequent research has suggested this could lead to benefits such as fewer calf mortalities, as levels of supervision is likely to be higher during the day.
In the past, Scotland’s Rural College (SRUC) has run trials across four commercially managed spring-calving beef herds in south east Scotland to test this theory.
Two of the herds involved were out-wintered, while two were calving on a housed system.
Dr Basil Lowman, beef specialist at SAC Consulting, was involved in the study.
He says: “The most interesting outcome was on one of the farms that out-wintered. The farmer had previously routinely gone up last thing at night in the dark to check the cows and rarely, even after half-an-hour or more, was able to find all of them.
“The biggest advantage to him was that going up to the field with the tractor and trailer at night to feed was that all the cows were there, waiting to be fed.
“If any were not there, he knew it was worthwhile searching for the missing animal as it was obviously calving or in some other trouble.”
The study found there was evidence to suggest that feeding later in the day resulted in fewer calves being born during the night, with the ‘day’ being 16 hours between 6am and 10pm, while the night was the eight hours between 10pm and 6am for the purposes of the trial.
Of the herds involved, it was calculated that feeding at 10pm resulted in 79 per cent of cows calving during the day, while feeding at 9am led to 57 per cent calving during the same period.
The results from the trial suggested the distribution of calving between day and night can be adjusted by time of feeding, but may be more applicable to spring calving cows, which have a large proportion of their daily feed intake controlled; made up mainly of roughage, which is consumed slowly.
SRUC also tested the theory on autumn calving beef cows in a stripgrazing system.
Dr Lowman says: “We used two adjacent fields, one of which was second cut aftermath.
“Cows were allowed onto a fresh strip of aftermath each evening when they were checked, before being taken back into the other field each morning.
“This also worked well, with only one cow calving in the aftermath before they were moved off at 7am. Dr Lowman also highlights research in Northern Ireland, which used the same principle around feeding times to influence when Friesian Holstein replacement heifers, due to be AI’d, came into heat.
“Using cameras, it was recorded that about 74 per cent of heifers fed in the evening came into heat between 7am and 8pm, whereas for those fed during the day, only 39 per cent did so during the same time period.”
Phil Cookes, stockman at Bassingbourn Limousins, Cambridgeshire, has been implementing this feeding system on a 100-head herd of pedigree Limousins for the past four years.
The group calves indoors from January and is fed ad-lib straw, plus 10kg/head of maize between 4pm and 5pm daily.
He says: “Since we started feeding this regime, we generally do not get a calf much after 10pm or before 6am. About 40 have calved since the beginning of January this year and, so far, only two have been outside this window.
“Aside from the odd one, most cows tend to calve between 11am and 3pm.
“A lot of people’s systems might not suit it. Those feeding bailed silage, for example where the animals eating is not so restricted, but I would recommend it to anyone who thinks it would suit their system, as it definitely does work.
“I got the idea for this system of feeding from my dad a few years ago and, as soon as we switched, the difference was noticeable.
Before this, we were feeding in the morning and cows were calving all over the place.
“We have not changed anything else in the system, only the time the cows were fed we have found although we still keep an eye out, we are less worried about calving problems at night as well as reducing out-of-hours vet calls.”