Choice of breed of bull & EBVs This is the third of a series of 12 articles on Simon Frost’s suckler herd at Youlgreave in Derbyshire. Simon achieves top 1% performance with his upland herd of 125 Limousin x Holstein Friesian cows put to Charolais bulls which is the basis of the Farmers Weekly/Harper Adams Beef Focus Farm concept. The first article outlined the background to the project with an overview of Simon Frost’s farm and his management strategies. The second article covered choice of cow breed and cow winter management. This article focuses on choice of terminal sire and use of EBVs.
Choice of terminal sire breed
Choice of terminal sire is often a hotly debated topic amongst suckled calf producers. Most have their preferences and can justify their allegiance to their chosen breed.
The last time beef breeds were independently evaluated in the UK was back in the 1970’s by the MLC! The most recent breed evaluation work was done in the 1990’s in Ireland at The Grange Research Centre. Although it was with dairy-bred crosses the data is still very relevant. The results are what we would expect and show that the Continentals are faster growing, leaner and show better conformation than the Native breeds which are easier calving.
Table 1. Relative performance of Beef x Friesian steers (Friesian = 100).
|Gestation Length||% Diff Calvings||Carcase wt./age||Conformation||Fat Score||Muscle wt./age|
(Source: Grange Beef Research Centre 2001)
Over the past 20 years all of the breeds have made significant improvements in growth rate and Signet and Breedplan data shows that some breeds have increased their 400 day weights by over 70kg. The Angus and Hereford have changed dramatically with the infusion of North American genetics but the Simmental with the Angus have made the most breed improvement of all the breeds. Since high growth rates are correlated to increased calf birth weights this subsequently creates issues with calving difficulties. Have we reached a point where our beef cattle are ‘big enough’ and breed societies now need to focus on other traits? The recent increase in the price of cereals and therefore ability to finish of forage is also another consideration for some breeds.
In a recent survey of English suckler herds by EBLEX it was found that the Limousin was the predominant sire with 33% of bulls followed by the Charolais with 17%. The Angus, Blonde and British Blue were all at 11% with Simmentals at 7%. If the survey had included Scotland then the use of Charolais and Simmental would have been higher since these two breeds predominate north of the border.
The Charolais was once the predominant terminal sire breed in the suckler herd. Calving difficulties with the Charolais is one of the main reasons why a number of commercial suckler producers in the past two decades have moved away from the Charolais to the easier calving Limousin. However there are now anecdotal comments that calving ease is becoming a problem with some Limousin bulls which is logical since the breed has significantly increased its 400 day weights over the last 20 years.
The Charolais is the choice of Simon Frost since this breed is recognised for having the highest growth rates of any of the terminal sire breeds. The growth, frame and stature of the Charolais complements the ‘fine-boned’ Limousin x Holstein which is the choice of suckler cow at Hopping Farm.
The data in table 1 shows that on average that the Charolais has the highest incidence of calving difficulties but it MUST be stated that there is more variation within a breed than between all of the major beef breeds and that there are easy calving Charolais bulls as well as very hard calving Charolais bulls. Simon Frost spends a considerable amount of time studying the bull sale catalogues to search for ‘curve benders’ – easy calving bulls identified by EBVs but with very high growth rates and muscle scores.
Ease of calving is an absolutely essential priority with today’s suckler herds which need to move to easicare systems requiring less labour thus following the trends led by the sheep industry.
In a recent study by the SAC three Charolais bulls with different calving ease EBVs were compared. Calving score is based on a scale from 1 (unassisted) to 5 (caesarian).
Table 2. Relationship between calving ease EBV and % calves born.
|Calving Ease EBV of sire||Calving Score (1-5)||% Calves born alive|
(Source SAC, 2004)
The most appropriate statistic is that the bull with the positive calving ease score resulted in 100% calves born alive. Based on a calf 200 day weight of 280kg for the easy calving bull the calves from the hard calving sire would need to be on average 24.3kg heavier to produce the same total calf weaning weight. This simple calculation also ignores the potential issues of reduced fertility with cows having suffered increased calving difficulties.
The beef industry must move forward and embrace the science of EBVs to progress breed improvement. Breed improvement is a ‘long term issue’ but with high feed prices it is even more imperative that we feed ‘well bred’ cattle sired by bulls with high Indexes. In a recent trial at Harper Adams dairy-bred calves from Limousin bulls with either a Top 1% or Bottom 1% Beef Value were intensively cereal finished. The performance of the bulls from the Top 1% Index sire smashed the EBLEX target for a slaughter weight of 570kg at 14 months old for Continental cross dairy-bred bull.
Table 3. Performance of progeny from Top 1% and Bottom 1% Bulls.
|Top 1% Bull||Bottom 1% Bull|
|Calving ease score (1-5)||1.54||1.46|
|Slaughter wt (kg)||584.5||574.1|
|Age at slaughter (months)||13.3||14.1|
|Carcase wt (kg)||330.1||312.1|
|Kill out (%)||56.4||54.4|
|Carcase daily gain (kg)||0.76||0.67|
|Conformation score (1-7)||3.92 (R)||3.54 (R/O+)|
(Source Harper Adams 2008)
The bull calves from the Top 1% sire finished 25.1 days earlier with carcase weights some 18kg heavier. Overall performance on every measured trait was statistically different apart from calving ease which was similar for both bulls. The earlier finishing and increased slaughter weight and improved carcase grade of the calves from the Top 1% bull with today’s beef and cereal prices is worth a phenomenal £116.24 per head. If each bull sires 200 calves then you could in theory afford to pay £23,248 more for the Top 1% Index bull!
In the Harper Adams study the calves were from Holstein cows and it is interesting to note that the calves from the Top 1% bull recorded 0.76kg carcase gain from birth. Daily carcase gain and not daily live weight gain is what we should be talking about to favour breeds with high kill out percentages. Simon Frost’s bull calves last year recorded a daily carcase gain from birth to slaughter of 0.94kg!
The beef industry must move forward and adopt the science of EBVs. Numerous studies have shown that they work and the financial rewards are significant. The industry change from selecting bulls with fancy masculine heads. What value is a head to the meat trade – NONE!
The fascination for big back ends should also end. The highest value of the carcase is in the loin and breeders MUST focus on this area and have bulls with stretch and depth of loin. The potential move to video image analysis (VIA) in some abattoirs which can predict meat yield and hence pay premiums is a step in the right direction since this should start to reward breeds with most beef in the high value parts of the carcase.
A bulls EBV’s may change slightly over time but that is due to more performance data becoming available on that bull and hence improving accuracy. The pedigree breeders must be honest about recording calving ease and with time more data on an individual bull and hence increasing accuracy of Calving Ease EBV will catch out breeders who falsify their data. The minimum requirement is 50% accuracy for the Calving Ease EBV when selecting a bull unless he is a young bull from a breeder you can trust.
Have faith in EBVs and buy bulls with top figures! Many farmers who dismiss EBVs are usually pedigree breeders with bulls that have poor figures or have bought bulls very low accuracy figures. Simon Frost has faith in EBVs and achieves top 1% performance!
Simon Frost’s guideline to EBVs
- Simon’s recent bull purchases include Balthayock Clifford (Terminal Index +45) and Balthayock Elector (TI +44). Both are top 1% bulls and Elector was bought this February at Stirling, Simon Frost’s parameters for the various EBVs that he looks for when buying a Charolais bull are as follows:
- Calving ease direct: Must be a positive figure – the higher the better.
- Gestation length: Ideally negative but up to +1 is acceptable
- Birth weight: As low as possible. Below +2 is acceptable.
- 200, 400 and 600 day weights: The 400 day weight EBV should be a minimum of at least 20 kg above breed average. A 600 day weight EBV above breed average is less critical since the calves are being finished at about 450 days of age.
- Eye muscle area: Ideally this should be over 6 and will influence carcase grades targeting U+
- Fat depth: This should be negative so that the bulls will grow without laying down fat which is inefficient
- Retail Beef Yield: Over 2 and as high as possible and
- The EBVs of Balthayock Elector purchased by Simon Frost at Stirling in February 2011 are shown in table 4.
Table 4. Balthayock Electors EBVs.
|Calving Ease Direct (%)||Gestation Length (days)||Birth Wt (kg)||200 day wt (kg)||400 day wt (kg)||600 day wt (kg)||Eye Muscle Area (sq cm)||Fat Depth (mm)||Retail Beef Yield (%)|
|Balthayock Elector EBVs||+2.6||-0.7||+2.4||+35||+61||+67||+6.1||-0.8||+2.6|
|Charolais Breed Average||-0.2||+1.2||+2.5||+24||+38||+43||+2.9||-0.3||+0.9|
Selecting bulls with the above EBVs results in progeny with the potential for very high growth rates with U grade carcasses. Last year 56 bull calves recorded a carcase weight of 438kg at 447 days (14.6 months) old which is exceptional performance and following articles will report on the progress of the 2010 calf crop which are being intensively finished by Alan Dore at Galpwell near Chesterfield. Feed intakes are being monitored to measure the efficiency of growth of both the bull and heifer calves.