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Dr. Harvey Domoslai, DVM
Corman Park Veterinary Services
5 miles West of Saskatoon, sk
on Highway 14 at Saskatoon Livestock Sales
Full facilities for the management of equine health issues.
Dr. Harvey Domoslai, DVM
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A Loonie sized stone was removed from this geldings urethra at the end of his penis.
September 7, 2014 18:41
This is an unusual case of a mare and hi-tensile wire. She got her hind leg tangled in hi-tensile wire today.
There were 3.5 wraps around her hind leg. The owner could not see much of the wire and assumed that it had cut deep into the leg even though there was no blood present.
This is immediately after cutting the wire off the leg. No skin cut at all, leg seems to be normal temperature below the wire.
5 hours after, treated with bute and cold water hosing.
August 1, 2014 11:36
By Sean Thompson, BSc, AAg, Regional Livestock Specialist
While we have the option to go indoors or dress appropriately during the hot summer months, our livestock can only cope with the heat by changing their behaviour or through physiological responses. It is important that livestock have access to adequate water and shade in order to prevent heat stress throughout the summer.
What is heat stress?
Heat stress occurs when animals experience warm environmental conditions which prevent them from adequately dispersing body heat. The ideal ambient temperature for cattle is between 5 and 25°C, with variation among animals depending on certain factors (e.g. stage of growth, production, age). As the outside temperature increases beyond this range, heat loss becomes much more difficult. Cattle maintain a constant body temperature by regulating heat loss. They primarily dissipate heat from the surface of their skin, either directly to the air (radiation and convection), to a cool surface (conduction), or through evaporation of sweat. However, when conditions become extreme a cow's ability to lose heat is limited. Significantly warm temperatures will decrease the amount of heat that an animal can lose to its surroundings and high humidity reduces the evaporative cooling potential.
Negative effects on livestock
Cattle will generally not graze under extreme heat since 1) eating increases heat production and 2) grazing usually takes place in non-shaded pasture. If warm temperatures extend into the evening or last for several days at a time, this can result in significant reductions in animal performance, including lower calf gains, less milk production, and poor feed conversion. As well, prolonged exposure to heat can affect reproductive efficiency. If livestock are overheated and spend the day trying to cool off, normal breeding behaviour may be negatively affected. The heat can also cause physiological effects, such as reduced embryo survival in cows and decreased sperm production and quality in bulls. The consequences for herd bulls are particularly important to consider as it may take several weeks for them to fully recover, which would result in cows not being bred during that time.
Signs of heat stress
There are several symptoms that you should watch for to determine if your cattle are experiencing heat stress. Open mouth panting with the head lowered and extended is an obvious sign of overheating. This will be characterized by heavy "puffing" and noticeable sweat on the neck and body. In severe cases animals will also begin to slobber. When grazing cattle become heat stressed they seek relief by finding shade or water to wade in. One or any combination of these signs in your herd could indicate that animals are struggling to maintain a constant body temperature. Special attention should be taken when sudden or abrupt hot conditions occur because cattle are more susceptible to overheating in these situations compared to gradual increases in ambient temperature.
Two necessities for livestock on pasture are adequate shade and water. Shade can be provided by either trees or man-made structures, which is important because direct sunlight can increase the temperature an animal experiences by 3-4 degrees above the air temperature. A clean supply of water is also essential for grazing cattle. Beef cows will drink approximately 40-60 liters of water per day, but that can nearly double when extreme heat conditions exist. Not only quality but quantity and access to water is important; a rule of thumb is that cattle should not have to travel more than a ½ mile in hilly terrain or 1 mile on flat ground to access water. Additionally, taking measures to ensure fly control will reduce overcrowding and thus the risk of overheating. Lastly, avoid working or transporting cattle during the day as the increased heat production from handling will only add to their heat stress. If cattle must be worked or moved it should be done in the early morning.
For more information on livestock management, contact your Regional Livestock Specialist, or call the Agriculture Knowledge Centre at 1-866-457-2377.
March 20, 2014 09:41
Question: We have a bottle feeding lamb who seems to be listless and breathing like a horse with heaves.
Should it get antibiotics? The lamb is about 12-15 pounds, born March 3.
Answer: Lambs are very susceptible to pneumonia. Treat with antibiotic immediately, be certain that the antibiotic is for use on lambs and pneumonia.
Monitor the lamb closely. -Dr. D.
March 20, 2014 09:14
Question: Hi, we have a cow, 9 years old, that has managed to pull a horn off. (Seen Mar 4-2014) I didn't think such an event was possible! The horn was found in a feeder several days later. I am curious as to what will become of the tissue that supported the horn. I noticed today that she must have given that base a knock and caused a wound that has shed blood once again. I welcome your comments regarding this. • It left the horn-shaped base as can be viewed in the first pic. And the sloughed horn that I picked up in the feeder is completely hollow. Thanks! -Cheryl H.
Answer: Then I would expect it may grow back similar to a broken part of hoof or missing nail on a person. The tissue left is horn corium, tissue that nourishes and supports the horn tissue. It will likely have granulation tissue on it now which bleeds very easily. If the cow is hard on it, or if it is too damaged, it may be better to have her dehorned and the site cauterized on that side. Or have a decorative brass cover made ;0) Dr. Lisa Wayman
September 13, 2013 10:33
Preg checked yesterday and calved today
September 10, 2013 19:54
This horse sustained a simple cut in pasture.
It is now quite sore and festering.
Treatment includes bandaging, lot of hydro and is on meds.
Photo Credit: Dr. Domoslai
September 10, 2013 19:41
We are a full service veterinary clinic.
A nice surprise came in for a regular family checkup,
a very attentive Momma
her basket full of puppies!
Photo credit: Dr. Domoslai DVM
September 7, 2013 11:32
September 6, 2013 07:10
During the month of August, two horses in Saskatchewan were confirmed to have West Nile
Virus (WNV). Both horses were treated and have recovered uneventfully. The first case, reported on August 6, occurred in RM 222 (Craik). The latter case, reported on August 12, occurred in RM 4 (Coalfield).
Horse owners and their veterinarians are reminded that WNV remains a risk in many parts of the province.
The following is excerpted from Saskatchewan Health’s Saskatchewan West Nile & Culex Report, August 30, 2013:
West Nile Activity Will Persist Into the September Long Weekend
West Nile Virus Risk
Although Culex tarsalis numbers have been declining in our traps, the warm evening temperatures are still causing some 2nd generation Culex tarsalis females and other species to remain active and biting. The arrival of the 2nd generation was delayed this year and was caused in part by the late spring and cool weather we encountered at the end of July. We may continue to see some more positive pools and we still have the potential to see infections going into the Labour Day long weekend. The forecasted trend to cooler temperatures next week will certainly limit mosquito activity to the warmer afternoon and early evening period. Furthermore, people will start to cover up more consistently as the evening and night-time temperatures cool off. Fortunately the overall all level of virus cycling in birds and mosquitoes has been delayed and limited this year, and the risk of acquiring a WNV infection has been lower than in previous years.
As we enter September and early fall, people should continue to avoid getting bitten by mosquitoes, at least until we get a hard frost. There are still a few mosquitoes that will be active on warm days and evenings, including Culiseta inornata and Aedes vexans. Although these are potential carriers of WNV, particularly in high activity years, they are not particularly competent vectors for human disease.
September 3, 2013 12:04
Rhino is an infectious horse disease caused by an equine herpes virus. Most infections result in mild respiratory signs, however, the virus can cause fatal nervous system infections.
Horse to horse spread is normally by nose to nose contact but people and equipment can spread infection as well. Therefore, isolating sick horses and practicing good biosecurity is imporant.
Equine Herpesvirus (Rhinopneumonitis)
Equine herpesvirus type 1 (EHV-1) and equine herpesvirus type 4 (EHV-4) can each infect the respiratory tract, causing disease that varies in severity from sub-clinical to severe and is characterized by fever, lethargy, anorexia, nasal discharge, and cough. Infection of the respiratory tract with EHV-1 and EHV-4 typically first occurs in foals in the first weeks or months of life, but recurrent or recrudescent clinically apparent infections are seen in weanlings, yearlings, and young horses entering training, especially when horses from different sources are commingled. Equine herpesvirus type 1 causes epidemic abortion in mares, the birth of weak nonviable foals, or a sporadic paralytic neurologic disease (equine herpesvirus myeloencephalopathy-EHM) secondary to vasculitis of the spinal cord and brain.
Both EHV-1 and EHV-4 spread via aerosolized secretions from infected coughing horses, by direct and indirect (fomite) contact with nasal secretions, and, in the case of EHV-1, contact with aborted fetuses, fetal fluids, and placentae associated with abortions. Like herpesviruses in other species, these viruses establish latent infection in the majority of horses, which do not show clinical signs but may experience reactivation of infection and shedding of the virus when stressed. Those epidemiologic factors seriously compromise efforts to control these diseases and explain why outbreaks of EHV-1 or EHV-4 can occur in closed populations of horses.
Because both viruses are endemic in most equine populations, most mature horses have developed some immunity through repeated natural exposure; thus, most mature horses do not develop serious respiratory disease when they become infected but may be a source of exposure for other susceptible horses. In contrast, horses are not protected against the abortigenic or neurologic forms of the disease, even after repeated exposure, and mature horses are in fact more commonly affected by the neurologic form of the disease than are juvenile animals.
Recently, a genetic variant of EHV-1 has been described (defined by a single point mutation in the DNA polymerase [DNApol] gene) that is more commonly associated with neurologic disease. This mutation results in the presence of either aspartic acid (D) or an asparagine (N) residue at position 752. Molecular diagnostic techniques can identify EHV-1 isolates carrying these genetic markers, although currently the implications of this finding for management of EHV-1 outbreaks, or individual horses actively or latently infected with these isolates, are uncertain. It is important to understand that both isolates can and do cause neurological disease, it is just more common for the D752 isolates to do so (it is estimated that 80-90% of neurological disease is caused by D752 isolates, and 10-20% by N752 isolates). Experts do not currently advise any specific management procedures for horses based on which isolate they are latently infected with, and it is possible that 5-10% of all horses normally carry the D752 form (this estimate is based on limited studies at this time). In the face of an active outbreak of EHV-1 disease, identification of a D752 isolate may be grounds for some increased concern about the risk of development of neurological disease.
Primary indications for use of equine herpesvirus vaccines include prevention of EHV-1-induced abortion in pregnant mares, and reduction of signs and spread of respiratory tract disease (rhinopneumonitis) in foals, weanlings, yearlings, young performance and show horses that are at high risk for exposure. Many horses do produce post-vaccinal antibodies against EHV, but the presence of those antibodies does not ensure complete protection. Consistent vaccination appears to reduce the frequency and severity of disease and limit the occurrence of abortion storms but unambiguously compelling evidence is lacking. Management of pregnant mares is of primary importance for control of abortion caused by EHV-1.
A variety of inactivated vaccines are available, including those licensed only for protection against respiratory disease, which currently all contain a low antigen load, and two that are licensed for protection against both respiratory disease and abortion which contain a high antigen load. Performance of the inactivated low antigen load respiratory vaccines is variable, with some vaccines outperforming others. Performance of the inactivated high antigen load respiratory/abortion vaccines is superior, resulting in higher antibody responses and some evidence of cellular responses to vaccination. This factor may provide good reason to choose the high antigen load respiratory/abortion vaccines when the slightly higher cost is not a decision factor.
Modified live vaccine
A single manufacturer provides a licensed modified live EHV-1 vaccine. It is indicated for the vaccination of healthy horses 3 months of age or older as an aid in preventing respiratory disease caused by equine herpesvirus type 1 (EHV-1).
All available vaccines make no label claim to prevent the myeloencephalitic form of EHV-1 (EHM) infection. Vaccines may assist in limiting the spread of outbreaks of EHM by limiting nasal shedding EHV-1 and dissemination of infection. For this reason some experts hold the opinion that there may be an advantage to vaccinating in the face of an outbreak, but in advance of EHV-1 infection occurring in the group of horses to be vaccinated. The vaccines with the greatest ability to limit nasal shedding include the 2 high-antigen load, inactivated vaccines licensed for control of abortion (Pneumabort-K®: Pfizer; & Prodigy® Merck), a MLV vaccine (Rhinomune®, Boehringer Ingelheim Vetmedica) and an inactivated vaccine, (Calvenza®, Boehringer Ingelheim Vetmedica).
Vaccination against either EHV-1 or EHV-4 can provide partial protection against the heterologous strain; vaccines containing EHV-1 may be superior in this regard.
Adult, non-breeding, horses previously vaccinated against EHV : Frequent vaccination of non-pregnant mature horses with EHV vaccines is generally not indicated as clinical respiratory disease is infrequent in horses over 4 years of age. In younger/juvenile horses, immunity following vaccination appears to be short-lived. It is recommended that the following horses be revaccinated at 6-month intervals:
Horses less than 5 years of age.
Horses on breeding farms or in contact with pregnant mares.
Horses housed at facilities with frequent equine movement on and off the premises, thus resulting in an increased risk of exposure.
Performance or show horses in high-risk areas, such as racetracks. More frequent vaccination may be required as a criterion for entry to the facility.
Adult, non-breeding horses unvaccinated or having unknown vaccinal history: Administer a primary series of 3 doses of inactivated EHV-1/EHV-4 vaccine or modified-live EHV-1 vaccine. A 4 to 6 week interval between doses is recommended.
Pregnant mares: Vaccinate during the fifth, seventh, and ninth months of gestation using an inactivated EHV-1 vaccine licensed for prevention of abortion. Many veterinarians also recommend a dose during the third month of gestation and some recommend a dose at the time of breeding.
Vaccination of mares with an inactivated EHV-1/EHV-4 vaccine 4 to 6 weeks before foaling is commonly practiced to enhance concentrations of colostral immunoglobulins for transfer to the foal. Maternal antibody passively transferred to foals from vaccinated mares may decrease the incidence of respiratory disease in foals, but disease can still occur in those foals and infection is common.
Barren mares at breeding facilities: Vaccinate before the start of the breeding season and thereafter based on risk of exposure.
Stallions and teasers: Vaccinate before the start of the breeding season and thereafter based on risk of exposure.
Foals: Administer a primary series of 3 doses of inactivated EHV-1/EHV-4 vaccine or modified-live EHV-1 vaccine, beginning at 4 to 6 months of age and with a 4 to 6 week interval between the first and second doses. Administer the third dose at 10 to 12 months of age.
Immunity following vaccination appears to be short-lived and it is recommended that foals and young horses be revaccinated at 6-month intervals.
The benefit of intensive vaccination programs directed against EHV-1 and EHV-4 in foals and young horses is not clearly defined because, despite frequent vaccination, infection and clinical disease continue to occur.
Outbreak mitigation: In the face of an outbreak, horses at high risk of exposure, and consequent transmission of infection, may be revaccinated. Administration of a booster vaccination is likely to be of some value if there is a history of vaccination. The simplest approach is to vaccinate all horses in the exposure area—independent of their vaccination history. If horses are known to be unvaccinated, the single dose may still produce some protection.
There remain concerns that heavily vaccinated horses may be more susceptible to developing neurological disease caused by EHV-1. This possibility is unsubstantiated and a subject of active investigation. To date, the use of a single vaccine immediately before exposure has not shown any association with an increased incidence of neurological disease.
Horses having been naturally infected and recovered: Horses with a history of EHV infection and disease, including neurological disease, are likely to have immunity consequent to the infection that can be expected to last for 3 to 6 months (longer in older horses). Booster vaccination can be resumed 6 months after the disease occurrence.
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