The New Zealand Hereford Association Member Newsletter - June 2009

Issue 100

Contents this issue:

1. Presidents Message
2. Guest Editorial: What Makes A Good Bull?
3. Bovine Venereal Campylobacteriosis
4. EBVs and ETs

 

1. President's Message

It is a privilege to be elected President of NZHA. John leaves me big shoes to fill and I look forward to your support and friendship. Many of you know me but for those who don’t here’s a bit of info. Our farm Locharburn is 2400ha, half-way between Cromwell and Wanaka were my wife Joyce and I run 200 registered Hereford cows, their calves and also fatten a few steers.

We also run 3000 fine merino sheep. Once again the Meat & Wool NZ Beef Expo was the focus for Hereford breeders with the week starting with Future Beef NZ Hoof and Hook Competition where many younger people competed in handling and judging events.

Congratulations to the Hain family who won the Hoof competition. Steak of Origin was a great success with a pure-bred Ezicalve Hereford entered by the Morrison family, Ardo winning the Best of British class.

Rob and Mary-Ann Burrows, Beechwood Herefords were third and fourth in this class - a great result for the Hereford Breed. Well done to everyone who took the time and effort to enter cattle, there were 350 entries this year.

The much awaited Beef Expo judging by Bruce Robertson and Philip de Waal from South Africa saw the Supreme Champion Hereford awarded to Waikaka Commodore 07069 from Laurie and Sharon Paterson’s Waikaka stud. He was then sold to Bruce and Margot Robinson Kokonga Herefords for $13000. Commodore came from the Tru- Test South Island Super Sires. Matapouri Ipod 07313 bred by Brian Clements and family was judged first in the North Island Tru-Test Super Sires. The only led entry was Wando Notable 711 and deserved being made Reserve Champion.

There were very good bulls from both Islands, and I believe the majority of prices received did not reflect the quality. The yearling bulls, led heifers and starter pack heifers sold very well. Special thanks to the Expo Committee led by Graham Potter and Sid Hain and all their many helpers.

The Hereford Hospitality area with a Hereford Prime BBQ lunch was great and enjoyed by all. Colin Corney, Jane Allen and helpers you did a great job and we are the envy of all other breeds. The day was capped off with a first class breed dinner where the Hereford show silverware, Merial-Ancare gold and platinum benchmark dams and the 2009 winner of the Hereford Herd of Excellence was announced by the one of NZHAs gold sponsors ASB. The recipients being John, Ros, Richard and William Morrison of Ardo Herefords, Marton. When you look at the costs of getting bulls to Expo, prices this year weren’t that good and Council will be having a hard look at Expo at our July meeting, any ideas and thoughts please contact your nearest Councilor or Natalie.

To date private bull sales have been very mixed, some good and others have seen a number of very good bulls passed in. The problem is the swing to Angus and a lot of cows going out because of dairy grazing. Dairying isn’t going to go away and many of you successfully target that growing market.

The good news is there is a lot less cattle going in to feed-loting in North America and Australia because of huge feed cost variations, the global crisis, and a swing to grass fed cattle by consumers wanting a better taste experience from their beef. Herefords are leaders in feed efficiency - a point we all need to push.

Our Hereford Prime Team will be looking hard at its business and opportunities over the next few months, with the desired result being a bigger kill. We’ll keep you posted on developments.

And special thanks to Natalie who ends up doing a lot of the donkey work. Best wishes for an easy winter, early spring and a good calving.

Cheers Geof Brown.

Ritchie Robertson’s letter of a year ago set me thinking. As I recall it, he was lamenting the decline in the standard of Hereford cattle in New Zealand. I have some sympathy for his viewpoint but perhaps for different reasons. I propose to discuss this with particular reference to low-birth-weight cattle.

What constitutes a good bull (or animal)?

We tend to think of a good animal as one with sound structure, good cosmetics, good growth rate, well muscled, having good bone and spread of rib, and good colour and markings and so on. It’s hard to disagree with this.

The problem is, that the New Zealand farming scene is changing and has been doing so for at least the last decade. Traditional beef herds are shrinking, dairying is expanding and a considerable proportion of the national beef herd is made up of animals of dairy origin. And the problem with our traditional “good” animal - it has an association with calving problems when used in the dairy industry.

This is most evident in dairy heifers and many vets are advising their clients against using Herefords over their heifers. The Friesian heifer seems to be a very fragile animal and a slow calving may result in a dead calf, paralysis (and probable death) or at best, loss of production.

The economic losses soon outweigh the value of the bull or any potential gain from white-faced calves. Some beef herds are also avoiding Hereford bulls over yearling heifers, for example the ARC.

Trouble free calving a priority when mating yearling heifers.

It follows then, that trouble-free calving is a top priority for this market which is potentially vast. Although conformation is important, the most reliable predictor of calving ease is birth weight. The concept of low birth weight seems to generate a lot of heat among Hereford breeders and it is hard to understand why. The lowest 1% of current birth weight EBVs were normal for some of the top bulls 20 years ago (ie Braxton Giant) and no one suggested he was inferior. The big question is “how low does birth weight have to be to cause a minimum of calving problems?”

This is open to debate but I would offer some suggestions:

A) Birth weight as a trait is generally antagonistic to growth, ie lower birth weight generally equals lower growth rates. There are some notable exceptions to this (curve benders). However, the problem in relation to calving ease is that every animal is made up of a mixture of genes and although an animal may have a low birth weight EBV, if it has growth genes there are likely to be some genes which when combined with the breeding female will produce a calf of larger birth weight. This could mean a few large calves with potentially disastrous results.

B) Birth weight and growth have a correlation with mature size. We would expect a low birth weight animal to have a small mature size. My point is that to obtain consistency of low birth weight in the progeny of a bull both superior growth rates and larger mature size may work against this.

How much growth do you need?

Over the past 20 years or so, we as breeders have made great progress in selecting for superior growth rates and this is part of the reason Herefords have lost favour with the dairy industry. An animal needs to be able to pass on enough growth genes to its progeny to enable them to grow efficiently to the point of slaughter. The ability to finish at the required time is also important economically. This means that for an animal to be finished at 18 months, 600 day growth is less important and the test of adequate growth is whether it can attain slaughter weight by this age. Other factors likely to be relevant are efficiency of feed conversion (potentially better in a small animal) and fat cover. So, how much growth do you need? Enough to reach a minimum slaughter weight at the desired time.

The Customer is Always Right.

This was the business philosophy of Robert A Laidlaw who founded the Farmers Trading Company and made it into a very successful business. If we want to supply a market, we must find out what the market wants and do our best to meet their requirements and this will be more than just supplying a bull. It will not be easy given our need to balance ease of calving with adequate growth, the feeding regimes of dairy heifers and the intolerance of some dairy farmers. However, the market is potentially vast and beef cattle are likely to be in short supply. This will create opportunities.

A Good Bull?

We all have a vision as to what our ideal animal would be like – it’s part of breeding. Not all our ideals will be the same, this is positive as diversity has been one of the breed’s strengths. During times when the breed has changed there have also been a number of animals which have been criticized but have nevertheless been instrumental in facilitating change. Perhaps we should broaden our ideal and while retaining the basics of reproductive ability and soundness, evaluate an animal taking into account its final purpose.

3. Bovine Venereal Campylobacteriosis

Contributed by Te Anau based veterarian, Jill Sloan BVMS MRCVS.

Causative Agent

Campylobacter Fetus subspecies Veneralis causes the worldwide disease Bovine Venereal Campylobacteriosis (BVC) or ‘vibriosis’. This bacteria is highly adapted to the genital mucosal lining of sheath and vaginal cavities of cattle. It is a very fragile bacteria and only survives for six hours when removed from the sheath lining or vagina of cows. Hence this makes it very difficult to culture.

Clinical Syndrome

BVC is characterised by temporary infertility of female cattle and occasional abortion. Bulls act as asymptomatic carriers which also occurs in cows, albeit much less commonly. Symptoms in cows include irregular extended oestrus cycles, infertility through endometritis (infection/inflammation in the uterus) and early embryonic death. Disease transmission is venereal, spread primarily by infected bulls during mating, but bull to bull transmission and transmission via semen can occur. Undertaking the service capacity test or ‘blocky’ test can be a very effective way of spreading BVC in your herd. Cows that have recovered from BVC achieve partial immunity and when reinfected their fertility is only marginally impaired. The immunity wanes after 3-4 years unless continued exposure to BVC. Originally it was thought that bulls not previously mated or mobbed with older bulls should be ‘clean’ but from work I have recently undertaken I would strongly question this and definitely not assume any ‘virgin’ bull was ‘clean’.

Current Testing Methods

Historically culture has been the only method of diagnosis. With the bacteria being very fragile and does not like to live outside the host environment, culture results have been poor despite the use of special transport and culture medium. Now there is a new PCR test available that looks for DNA of BVC. It is a highly sensitive and specific test for BVC picking up a very small amount of the bacteria. The bacteria does not need to be kept alive. A corrugated plastic scraper attached to a long handle is used to scrape across the glands of the prepuce. The aim is to catch mucous, debris and thus bacteria in the corrugated groove. This sounds worse than it is for the bulls. I have found that with the bulls in a head bail and the hind leg tied so they can’t kick forward on the side I’m working the test can be undertaken very efficiently and effectively. Currently only a small number of herds have been tested but so far the prevalence is 57%. More research is required to quantify the presence and the effect on herd fertility of BVC in NZ. It appears from the experience of other vets that Campylobacter fetus subsp. Venerealis can be found in herds with satisfactory reproductive performance. Hence a positive result with the PCR test does not always mean poor fertility but it could be a factor. I would certainly discourage the mating of positive bulls with heifers. The complex nature of BVC makes long term control in herds very challenging. Treatment of infected bulls is an option, and initial findings show the bacteria is sensitive to antibiotic treatment either given into muscle or as a sheath wash. Thought will have to be given to strategic timings of treatment of bulls.

4. EBVs and ETs.

The NZ Hereford Council Technical Committee have been discussing with ABRI, the issue of EBVs of ET calves that have in some instances changed markedly from the time of purchase to the recording of the first progeny. As a result of these discussions, it was felt that we should inform breeders of what can happen and some points to note.

It seems that the issue is basically a problem of small analysis groups, whether ET or natural. Breeders need to be aware that even at 75% accuracy a 4 point movement either way is possible and considered acceptable.

For example birth weight of +4 changing to 0 or +8 is acceptable at 75%. Therefore one needs to ascertain the size of the contemporary group, so that one can make an informed decision about the likelihood of there being a change to the EBVs when progeny arrive, as most two-year-old bulls in NZ have BW accuracy of around 75%. Also the use of fully recorded Herefords as recipient dams would help the accuracy of the EBVs.

I draw your attention to the following comments from ABRI.

Accuracy values reflect the amount of information behind the estimates. One observation that may be made is that animals

1. that have their own observations ignored in Breedplan analyses (because of single animal contemporary groups) have “larger” EBV changes when the performance of their progeny is eventually analyzed than do parents that have had their own performance effectively analyzed. This is definitely not true in all instances, but more importantly, the accuracy value will have reflected this difference.

2. The main issues relating to ineffective (or relatively ineffective) contemporary groups are single animal groups and single sire groups. In single animal groups the animals performance can not be utilised as there are no other animals with which to make comparisons. In single sire groups, the difference in performance of the individual animals can be used to obtain EBVs for the individuals but the sire gets no benefit as there are no other sires represented with which comparisons may be made.

3. In relation to the ET animals - if there are no recipient dam details on file or if the breed of the recipient dam is different to the other recips - they are analysed in single animal contemporary groups (meaning that their individual performance is not affecting their EBVs) and their EBVs and accuracy values are “mid-parent values” of their parental EBVs and accuracy values.

4. The best solution is to encourage breeders to supply the best information. For ET calves, this means supplying full recipient dam information (tag, breed, age). Breeders undertaking ET programmes can also be encouraged to include more than one flush in the embryo programme (so that there are different sires & dams represented in contemporary groups).

Philip Shepherd
NZHA Technical Committee chairman.

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