Mares Research Articles

Ationship between ultrasonic characteristics of the corpus luteum, plasma progesterone concentration and early pregnancy diagnosis in friesian mares

The purpose of the present study was to evaluate the change in cross-sectional area of the early corpus luteum (CL) and progesterone production in relation to subsequent pregnancy diagnosis. The cross-sectional area of the CL of 75 Friesian brood mares was measured by ultrasonography on Day 1 or 2 and Day 8 or 9 after ovulation. The change in cross-sectional area was expressed in a volume ratio. Plasma progesterone concentrations were measured on Days 8 to 9, and ultrasonography to determine pregnancy status was carried out on Day 17 The data obtained were analyzed by using a multiple logistic regression model. There were significant differences in the age, volume ratio and progesterone concentration between pregnant and nonpregnant mares. Pregnancy on Day 17 was related to the change in size of the CL up to Days 8 to 9 and progesterone concentration on Days 8 to 9. These differences between pregnant and nonpregnant mares might reflect the first luteal response to pregnancy.

A survey concerning the equine fescue toxicosis malady

The objective of this research was to determine the scope of equine fescue toxicosis, current procedures to control the disease, and to gain veterinary insight to possible new therapies. A survey was developed with help form experts in the area of fescue toxicosis. From a list of members of the American Veterinary Medical Association (AVMA), a sample was obtained by selecting large animal/equine veterinarians from states where fescue toxicosis is common. These states included: Alabama, Arkansas, Georgia, Illinois, Indiana, Kentucky, Missouri, Mississippi, North Carolina, Ohio, South Carolina, Tennessee, Virginia, and West Virginia. One-fifteenth of the veterinarians (515 total) were mailed questionnaires; 207 responded. Veterinarians were grouped into regions based on latitude. Region 1 included veterinarians practicing north of 39.0° latitude; Region 2 included veterinarians practicing between 36.5° and 39.0° latitude; and Region 3 included veterinarians practicing south of 36.5° latitude. A majority of horse pasture in the area of the survey is comprised of at least 50% fescue, with approximately 70% of the pasture being at least partially comprised, of fescue. Almost 50% of the brood mares in the area of the survey are exposed to endophyte-infected fescue. Many gravid brood mares in the area of the survey were suffering from acute and subacute symptoms, with over 43% warranting some kind of management technique to prevent toxicity from occurring. A large majority of veterinarians in the area of the survey feel that fescue toxicosis is, to some level, a problem. Current management techniques can be tedious and expensive. New management techniques and/or therapies are needed to handle the problems associated with equine fescue toxicosis. A large majority of veterinarians in the area of the survey feel an effective drug therapy would be valuable in treating equine fescue toxicosis. If a drug therapy were developed, a daily feed additive or an oral gel would be the most popular method of dosing with veterinarians. As a result of trends noticed in the rates of equine fescue toxicosis in different areas, statistical analyses were conducted on data generated from this survey along regions that seemed to have different infection rates. There was no difference (P>0.05) in levels of fescue in pastures, mare exposure to the endophyte, and mare expression of acute or subacute symptoms between regions 2 and 3. There was a difference (P<0.05) between region 1 and regions 2 and 3 for all of the factors tested except for number of mares seen by veterinarians.

Passive transfer, rate of decay, and protein specificity of antibodies against equine arteritis virus in horses from a Standardbred herd with high seroprevalence

Objective— To determine rate of decay of passively acquired antibodies in Standardbred foals on a farm with a high seroprevalence to equine arteritis virus (EAV) and to determine whether vertical or horizontal transmission of the virus was responsible for infection on the farm. Design— Repeated-measures study. Animals— 46 Standardbred horses (15 brood mares and their foals, 5 stallions, and 11 young horses). Procedure— Serum samples obtained from horses on the farm were evaluated by serum neutralization and western immunoblot analysis to detect EAV-specific antibodies. The half-life of passively acquired antibodies in foals was estimated by use of regression analysis. Results— Most (14/15) of the mares evaluated were seropositive to EAV. After suckling, their foals were also seropositive. Mean biological half-life for passively acquired antibodies in serum samples obtained from foals was 32 days (r2 = 0.61). The foal born to a seronegative dam and all 11 young horses from the farm were seronegative to EAV. At least 2 of 5 stallions on the farm were persistently infected carriers that were shedding virus in their semen. Immunoblot analysis of seropositive serum samples most consistently recognized the Μ protein of EAV. Clinical Implications— Analysis of these data indicated that a modified-live EAV vaccine can be administered to foals after they are 8 months old without risk of interference from maternal antibodies, regardless of serologic status of the foal's dam. Horizontal transmission of EAV via the respiratory tract apparently was uncommon on the farm, indicating that mares primarily were infected by venereal transmission of virus from carrier stallions. (J Am Vet Med Assoc 1998;213:839-842)

Modifications on the vulvoplasty procedure in mares

Modifications on the vulvoplasty procedure in mares

Treatment of agalactia in two mares

Treatment of agalactia in two mares

The Music of the Mares

The Music of the Mares

Can mares be classified as resistant or susceptible to recurrent endometritis

Can mares be classified as resistant or susceptible to recurrent endometritis

Nutrition of grazing brood mares and growing horses.

Nutrition of grazing brood mares and growing horses.

The Effect of Prostaglandin E2 on the Cervices of Dioestrous and Prepartum Mares

The Effect of Prostaglandin E₂ on the Cervices of Dioestrous and Prepartum Mares

Genotyping of isolates of Taylorella equigenitalis from thoroughbred brood mares in Japan.

Profiles of the genomic DNA of 104 strains of T. equigenitalis isolated from brood mares with contagious equine metritis in Hokkaido during the breeding seasons from 1980 to 1993, as well as those of five strains (SS28, EQ56, EQ59, EQ70 and HH139) previously isolated in Japan were examined after restriction digestion and crossed-field gel electrophoresis. These profiles were essentially identical to each other and the various isolates and strains appeared to have a common genotype, designated 'genotype J', with respect to two restriction enzymes, ApaI and NotI. These results suggest a common source for all these isolates obtained over the course of more than 10 years in Japan.

Estrogen from Ill-Treated Mares?

Estrogen from Ill-Treated Mares?

The Mawkin on Herrick's Hock-cart

In a poem written at Dean Prior in Devonshire sometime between 1630 and 1648, and addressed to the Earl of Westmoreland, Robert Herrick invites the Earl to watch a procession of harvesters bringing in the last load:Come forth, my Lord, and see the CartDrest up with all the Country Art.See, here a Maukin, there a sheet,As spotless pure as it is sweet:The Horses, Mares, and frisking Fillies(Clad, all, in Linnen, white as Lillies.)The Harvest Swaines, and Wenches, boundFor joy, to see the Hock-cart crown'd.

XO mares: are they mice or men?

XO mares: are they mice or men?

Seasonal Changes in Ovarian Activity and Estrous Behavior of Thoroughbred Mares in a Tropical Environment

Seasonal Changes in Ovarian Activity and Estrous Behavior of Thoroughbred Mares in a Tropical Environment

Functional State of Primary and Secondary Corpora Lutea in Pregnant Mares

Functional State of Primary and Secondary Corpora Lutea in Pregnant Mares

Absence of an Association between Melatonin and Reproductive Activity in Mares during the Nonbreeding Season

Absence of an Association between Melatonin and Reproductive Activity in Mares during the Nonbreeding Season

Effects of short-term exposure to and removal from the fescue endophyte Acremonium coenophialum on pregnant mares and foal viability

Effects of short-term exposure to and removal from the fescue endophyte Acremonium coenophialum on pregnant mares and foal viability

DIAGNÓSTICO ECOGRÁFICO DAS ALTERAÇÕES UTERINAS E OVARIANAS EM ÉGUAS PURO SANGUE DE CORRIDA

RESUMO As imagens ecográficas de algumas alterações freqüentemente encontradas no trato reprodutivo de éguas Puro Sangue de Corrida, tais como hematomas e tumores ovarianos, cistos endometriais, coleções de fluido intra-uterino e hematoma de parede uterina são descritos com propósito educativo.

Equine pituitary neoplasia: a clinical report of 21 cases (1990-1992).

The records of 21 horses with an adenoma of the pars intermedia of the pituitary gland were reviewed. The animals comprised nine Dutch warmblood horses and 12 ponies. They ranged in age from 12 to 30 years (mean +/- sem 21 +/- 1.3 years) for 20 of the horses, and comprised 13 geldings and eight mares. All the animals showed hirsutism. In 1991, nine horses were diagnosed as having the adenoma, equivalent to 0.5 per cent of the horses examined in 1991. The mean +/- sem survival time of four of the horses (from discharge to the development of complications which required euthanasia) was 192 +/- 59 days (range 120 to 368 days). Routine biochemical measurements were within their normal ranges except for a high alkaline phosphatase activity (768 +/- 487 iu/litre) and a high plasma glucose concentration (7.8 +/- 0.9 mmol/litre) in 16 of the horses; only six had a glucose concentration above 9.0 mmol/litre. The basal plasma concentration of adrenocorticotrophic hormone (ACTH) in the diseased horses was at least 191 pg/ml. Eight of the horses had mean plasma cortisol concentrations before and after the administration of 25 iu of synthetic ACTH1-24 of 168 +/- 21 (range 74 to 248) and 478 +/- 58 nmol/litre (range 248 to 771), respectively. Analysis of the urine of five of the horses revealed a mean specific gravity of 1.034 +/- 0.0034 (range 1.025 to 1.045).(ABSTRACT TRUNCATED AT 250 WORDS)

抗グロブリン試験陽性妊娠馬とその新生子ウマの血液学的性状

抗グロブリン試験陽性妊娠馬とその新生子ウマの血液学的性状