To date, there has been little if any demand for improved levels of feed efficiency in ruminants, but spiralling feed costs coupled with a growing urgency to produce more 'climate friendly' livestock could be the game changer to focus producers' breeding goals on the trait which has been shown to save in excess of £100 per head on one Scottish beef farm.

While many countries are already testing bulls for feed efficiency, the UK has lagged behind and there are huge differences between the top and the bottom performers as pedigree Aberdeen-Angus breeder, John Elliot has discovered.

As the first Angus breeder in the UK to test his young bulls for feed efficiency, John found his top rated bull for the characteristic required a phenomenal 523kg less feed than the average bull in the group to reach slaughter weight. At a conservative £200 average finishing ration price per tonne, this amounts to a massive £105 per head less in feed costs.

"Basically, the bull with the highest feed efficiency cost half a tonne less to feed than the average in the batch," said John who has been amazed at the results from the 63 Rawburn Aberdeen-Angus bulls in the first trial on the farm at Roxburgh Mains, Kelso.

"We really didn't expect to see as big a range in the results when our cattle have always had really good growth rates, but the most efficient bull required 3.6Kg of feed to gain 1kg of body weight compared to the worst bull for feed efficiency in the trial which required 6kg of feed."

Unsurprisingly, John, who is also trialling his pedigree Limousin and Beef Shorthorn bulls alongside other Aberdeen Angus bulls, believes the results have the potential to make huge financial and environmental improvements to all beef units if the results are taken on board.

"Recording for feed efficiency is the biggest step forward in performance testing at Roxburgh Mains, since we started to weigh our cattle in the 1980’s," he said.

"As an industry we must be aware of our image and be seen to be doing everything we can to make our product more environmentally friendly and trials in the US have shown that breeding cattle that are high for feed efficiency can reduce methane production by 30%.

"Recent trials at the University of Alberta and NSW Agri Research Station, have also shown that cattle that are feed efficient have the same results on grass-based systems. By using this data we hope to select for cattle that can give us the same output on less acres of grazing."

However, while John and his father, also John are convinced of the benefits of breeding cattle for improved feed efficiency, both were surprised by the fact that neither – despite their well-known stockmanship capabilities – could pick out the star performers visually, or from previous growth, muscle and marbling figures they had for individual bulls in the trial.

"There was no obvious visual type of bull that you would say had good feed efficiency figures, although the progeny of Nichols Expectation, a US-bred bull that we bought the semen rights from because he had the highest feed efficiency figures and growth rate on the Nichols ranch, Iowa, did fare the best."

That was in 2016, when John was viewing large scale feed efficiency trials in Aberdeen Angus herds in North America. Impressed by the results from such trials he did initially look to buy into the system, but held back due to the costs involved.

Instead, the semen rights to the highest combined bull for feed efficiency and growth, Nichols Expectation, and his dam, Nichols Bonnie, were purchased from the Nichols ranch, Iowa, which runs 500 head of pedigree Aberdeen-Angus cows.

Nichols Bonnie was then flushed and semen from Expectation has been used extensively in the 220 pedigree cows based at Roxburgh Mains and the 110 Angus females at Upper Huntlywood, Earlston.

In time, a more economical price enabled the purchase of the Growsafe feed efficiency system which is the oldest and believed to be the best in the world as it not only analyses animals independently but also allows the Elliots to compare their cattle against 250,000 worldwide, and, from no fewer than 23 different breeds. However, it cost a hefty £100,000 with another £20,000 having to be spent on a shed to maximise it's effectiveness.

The system is based on individual electronic tagging of all bulls in the trial, eight feed bunks and a four water troughs with constant weighing and measuring each time an animal goes to eat or drink.

At Roxburgh Mains, John's first trial revolved round 63 mostly eight-month-old Aberdeen Angus bulls by various sires, which were kept in pens of thirty. All were bedded on sawdust with the one constant ration fed for 64 days. They have an initial 14-day run on the mixture, with trial results based on the following 50 days of liveweight gain and feed intakes.

The entire trial revolves around knowing exactly what each animal consumes, therefore there is no silage or straw with the feed ration based largely on oats with some maxammon treated barley, distillers dark grains, sugar beet pulp and Neo-Lac. To replace the normal forage in the diet, a high fibre nut has been added to increase gut scratch and maintain rumen health. Nutritionally, the diet is made up of 85% dry matter; 12.6g of metabolisable energy per kg of dry matter and 15% crude protein.

As all cattle are electronically tagged, the amount each bull eats and drinks is recorded each time, with data fed directly to John's farm computer and through the cloud to Growsafe in Canada.

Basically when an individual animal goes to eat, it's ear tag is recorded along with the starting weight of the feed in the bunk. When it has finished eating and pulls away, the end weight of the feed in the bunk is measured and therefore the amount consumed by that animal is recorded.

Similarly, when an individual animal goes to drink, it steps on a scale at the same time, which records the weight of the animals. On average, each animal went to drink seven times a day and to eat eight times.

With recordings available from each animal on a daily basis – similar to that of a robotic milking machine – John is also alerted to any illness in the animals quicker than normal, purely because it could be drinking more or eating less.

"The system detected sick animals days before they showed any visual symptoms," said John who added that almost every animal flagged up for reduced intakes was running a higher temperature than normal.

Interestingly, while the farm can access individual daily feed intakes and weight gains, the actual feed efficiency results are not announced by Growsafe until after the 50-day trial.

The first trial at Roxburgh Mains has made for interesting reading with the average bull gaining 2.53kg per day.

To achieve that weight gain, the average bull required 4.20kg of dry matter to gain 1kg of body weight, with the best requiring just 3.03kg of dry matter to gain 1kg of body weight. This compares to the worst which required 6kg of dry matter to gain the same 1kg of body weight.

Results from Growsafe also revealed that the highest feed efficiency bull required 2.90kg less feed per day to make the same rate of gain as the average bull in the group.

This means the highest efficiency bull would require 523kg less feed than the average bull in the group to reach slaughter weight, which with a typical finishing ration costing a conservative £200 per tonne, points to £105 per head saving.

Having bought the semen rights of one of the highest Aberdeen-Angus bulls in the States for feed efficiency, his progeny performed particularly well in trial. However when growth was combined with feed efficiency it was offspring from the North American-bred bull, Rawburn Black Watch – a CCL Dateline son bred from DBRL Blackbird – that came out on top.

While the business has all the figures of their bulls, Growsafe put the data into an EBV that allows individuals to compare the animals against their group and also all others tested worldwide and also across breeds.