What are genotyping technologies?

The genotyping technologies that are currently being marketed to beef producers are based off of genetic markers that have been identified to be associated with economically important traits. The genotyping technologies are used to try to identify the underlying genetic predisposition for important traits so that producers can select for their superior animals early in the production process. A producer can have DNA extracted from an animal's sample of hair, tissue, semen or blood for future genomic testing. Specifically, these genomic tests evaluate genetic markers that are inherited by animals that are either high producers for a trait or low producers for a trait. The goal in using these technologies is to increase the accuracy of selection from traits ranging from growth, efficiency, carcass quality, fertility and disease resistance early in the production process.

How can genotyping technologies have limitations if we are looking at the genetic makeup of an animal?

The idea that producers could make selection decisions much earlier in the production process led to the commercialization of many genotyping tests. However, producers must really understand that the concept of selecting animals based on their genetic makeup is still in the early development stages for a couple of reasons. First, the genome is extremely complex, there are an estimated 30,000 genes and three billion individual nucleotides in the bovine genome. Researchers are still attempting to understand how these genes function physiologically, how mutations alter these functions and how inheriting a combination of markers will influence production. Second, many of the traits that producers are interested in, such as disease resistance and fertility, are lowly heritable and most likely influenced by multiple genes and thousands of markers. Furthermore, many genetic markers might influence multiple traits. As such, relationships among genes and markers on multiple genes need to be evaluated in order to make selection decisions more accurate and to avoid detrimental selection where we improve one trait and damage another. Lastly, many of these tests are breed or population specific as they have been developed in a specific breed or production system. Thus, not all these genetic markers may be useful for Utah beef producers raising cattle in a Utah beef production system.

Should a producer use genotyping technologies?

There are questions producers should ask themselves prior to implementing this technology into their selection. They are:

1. What traits am I trying to improve?
2. Are these traits highly or lowly heritable?
3. How much improvement in one generation or multiple generations can I expect to see by implementing this tool as part of my selection strategy?
4. Will I be able to cover the cost of testing (tissue collection, shipment, DNA extraction and cost of the DNA test) with the increased performance of my animals?

5. How were these tests developed and what type of animals were they developed in?

 

As previously stated, this technology has been around for many years but is still in the early development stages. While this technology may prove to be beneficial for some producers, it may not be cost effective or efficient for others. It is always important to know as much as you can about these technologies prior to implementation so that a decision can be made as to whether it is going to bring an added benefit to your operation. While genomic tests are still relatively new, they are getting more accurate and will continue to improve. As such, this technology, if further developed, will provide producers a new selection tool to make them more profitable and sustainable.

A new disease is creeping into our horse population of Utah. Equine Piroplasmosis (EP) is a tick-borne disease also referred to as babesiosis or theileriosis. Theileria equi and Babesia caballi are the parasitic agents that are spread by tick bites or through mechanical transmission by improperly disinfected instruments.

            Equine Piroplasmosis occurs naturally when ticks ingest blood from an infected horse and then bite an uninfected horse. Currently, there is only one known area in the U.S., located in southeast Texas, where tick transmission of EP has been shown to occur.Equine Piroplasmosis is also spread by humans using skin penetrating instruments without properly sanitizing these instruments or disposing of them between horses. These instruments include needles, syringes, dental equipment, tattoo equipment, and surgical tools. The majority of recent outbreaks in the United States have been attributed to iatrogenic transmission rather than the natural transmission via ticks. So far the spread in Utah is limited to horses in racing stables.

            The blood borne parasites attach to the red blood cells and cause their destruction. After a horse is infected it can take from 7 to 30 days to show signs of the disease.   Cases of EP may be inapparent, mild or acute. Mild cases can appear as loss of appetite or weakness, while more acute severe signs include fever, anemia, weight loss, jaundice, fluid accumulation in the abdomen, decreased performance, edema in the lower limbs, and even death. After the initial stages of the disease, EP may become chronic. Horses can carry the parasites for long periods of time with no clinical signs. This leads to a horse becoming a carrier that can spread the disease to other horses by mechanical or natural routes. Diagnosis of EP is made by testing serum for antibodies to T. equi and B. caballi.

            With a positive horse options are limited. These include a life-long quarantine overseen by federal regulatory officials, euthanasia, or treatment. Treatment of EP is only permissible if the horse is enrolled in a USDA supervised research program. The goal of treatment is to completely clear the horse of infection. The positive antibody status of the horse remains for many months and, in some cases, up to 2 years after successful treatment and the horse must remain quarantined during this time.

            Prevention is vital to stop the spread of EP. Recent outbreaks have been isolated and caused by reusing needles and syringes between horses. The American Association of Equine Practitioners gives these guidelines:

ALWAYS

·         Use a new sterile needle and syringe for injections, whether into a vein or muscle or

         beneath the skin

·         Clean and disinfect equine dental, tattoo and surgical equipment between horses

·         Contact your veterinarian if your horse is sick and has signs of fever, reduced feed intake  

            Equine Piroplasmosis can be a devastating disease to horse owners and the horse industry. With current outbreaks being limited to the race horse industry, the Utah Racing Commission is requiring all horses entering a track to test negative first. With these measures in Utah and surrounding states we hope to be able to control the current and potential threat EP poses to our horses.

I grew up on a small potato farm in Southeast Idaho. I loved farming (except for picking rocks which we had plenty of). As a young boy I always thought the most important job on the farm was driving the tractor. One day I was asking my Dad why he wanted me to go to college instead of just stay on the farm and work. He said something that has always stuck with me. He said, "Driving the tractor is the easy part of farming. To be successful, you need to learn how to manage the other parts of farming". At the time I just thought he was trying to impress me with his fatherly wisdom. But the more I have thought about it, the more I believe it. For example, let's look at today's ag economy.

We are no entering a 4th year of low commodity prices and poor profitability. The outlook for 2017 does not look much different than 2017. Purdue University surveys 400 producers throughout the US to monitor sentiments concerning future outlook. The most recent survey produced a pessimistic future for 2017. 27% of survey respondents thought that corn prices would drop below $3.00 per bushel and only 34% of respondents thought corn prices would rise above $4.00 per bushel. The survey is also given to industry professionals, academics, and agricultural lenders. Their perspective was not much different from that of the farmers. Only 29% from this group thought that corn would rise above $4.00 per bushel.

But in the midst of this downturn, I hear stories of farms and ranches that are still being profitable. As I have visited with these producers, some common practices begin to surface. I will discuss three of those practices. (1) Knowing your cost of production and not on a per acre basis but on a per bushel basis. The University of Minnesota collects data on individual farmers throughout the US. They have found a dramatic difference in costs of production between profitable farms and low profit farms. The difference in profitability is not gained from a major difference in price per bushel received but from the price per bushel paid for operating expenses. (2) Develop strategic relationships. I have worked with a group of farmers that began to purchase crop inputs together in bulk. This provided close to $15-$20 savings per acre. In today's markets, that might be the difference between making versus losing money. (3) Develop a sound marketing plan and work with someone to help you implement that plan. I will use the soybean market as an example. This past summer there was a point where farmers could have locked in a profit with soybeans. Some farmers locked in the price but many farmers speculated that soybean prices would continue to increase. Unfortunately, soybean prices did not continue to increase and many of these farmers will struggle to break even.   It is a wise investment to work with a marketing specialist that you trust. This individual can help take the emotion out of decisions and work to implement a sound marketing strategy.   Today's commodity markets are highly volatile. The windows of opportunity to market wisely and make money are often very short. A marketing professional can help you take advantage of those windows.

As I said earlier, driving the tractor is the easy part. Managing a farm or ranch is where the difficulty comes. Managing and tightly monitoring your production costs, developing strategic relationships, and implementing a sound marketing plan will assist in surviving tough times.

"AR" (Anthelmintic Resistance) in Sheep and Goats

Dr. Lyle McNeal, Small-Ruminant and Wool Specialist

The United States, as in most of the developed countries globally, in recent decades are finding more and more of their sheep and/or goat flocks are becoming "AR" or internal parasites that are resistant to the dewormers (anthelmintics) available for the producers. In the United States, one of the most common internal parasites that affects our small ruminant population is the roundworm or nematode, Haemonchus contortus (barberpole, stomach worm). Because of the National level animal sales from various U.S. Regions, these internal parasites are more accessible in what we used to consider the open States of the West, i.e. Utah, Idaho, Colorado, Wyoming, etc. Although the genetics of the parasite plays an important role in this problem, more of issues that has resulted in parasite resistance, is largely due to management either a) deworming their animals too frequently; b) treating the entire flock/band; and/or c) under dosing levels of the anthelmintic (dewormer).

Traditionally, and since the 1960's, internal parasites have been controlled by frequent, regular administration of dewormers. However, with the emergence of multiple drug resistant parasites, new approaches are required in the 21st Century.

What is AR?

Anthelmintic (dewormer) Resistance (AR) is the genetic ability of the worm to survive a dose of anthelmintic which would normally be effective. It could also be described as 'drug tolerance' in worms. A worm is said to be resistant if it survives exposure to the standard recommended dose of the anthelmintic and can than pass this ability on to its offspring.

Sheep and goat performance drops versus the increasing proportion of resistant worms on the farm/ranch. The percent (%) of resistant worms that increase over time will result in production losses increase as more and more worms survive deworming treatment, causing damage to the gut of the sheep. In lambs this means reduced growth rates, but because the increase in resistant worms is slow and progressive, we either don't notice that performance is going down, or blame those losses on other factors, such as trace mineral deficiencies, bacterial infections, etc.

However resistance develops over time. What are the factors affect the speed that resistance develops?

These are some of the factors which define the rate resistance (AR) develops and on which can be summarized as:

1. Proportion of resistant worms on a farm/ranch - as this gets higher the faster you head towards serious diminished production. Working with your local veterinarian conducting fecal egg counts, before and after deworming can help determine estimates of resistant internal parasites too.

2. Frequency of deworming or anthelmintic use - every time we use an anthelmintic we select for resistance, because we kill susceptible worms and allow resistant ones to survive and reproduce.

3. Effectiveness (efficacy) of each deworming - under-dosing or using an anthelmintic to which there is resistance present will give resistant worms even more chance to survive and reproduce, thus speeding up the rate towards the dangerous levels of resistant worms.

4. Errors of live weights of animals - sheep and goat producers often underestimate the weight of their animals and do not give enough dewormer so many more worms survive treatment, increasing drug resistance. Animals should be weighed individually or dosed according to the heaviest animal in the group and dosing equipment should be checked frequently for accuracy.

In the end, we can agree that we need new and more effective anthelmintics developed, or as some producers are moving towards herbal and home brewed remedies. Regardless, internal parasites aren't going away from livestock.

For additional information, please feel free to email  lyle.mcneal@usu.edu or call (435) 797-2140 or 797-2162. The mailing address to mail your raw wool samples to: Dr. Lyle McNeal, Sheep & Wool Specialist, P.O. Box 4454, Logan, UT 84323-4454.