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Biomedical subjects

S W Ricketts

Publications and source records attributed to S W Ricketts.

At least 19 recordsLinked to original sources
PubMed2001

Biochemical markers of bone metabolism in growing thoroughbreds: a longitudinal study.

This study describes longitudinal changes in serum levels of biochemical markers of bone cell activity in a group of 24 thoroughbred foals from birth to 18 months of age. The markers of bone formation included the type I collagen carboxy-terminal propeptide (PICP), the bone-specific isoenzyme of alkaline phosphatase (BAP), and osteocalcin (OC). Levels of the cross-linked telopeptide of type I collagen (ICTP), a marker of bone resorption, and the N-terminal propeptide of type III collagen (PNIIIP), a marker of soft tissue turnover, were also measured. Levels of all markers fell significantly between birth and 18 months of age (70-80 per cent); this decrease being most marked between 0 and 6 months. However, a transient increase in levels of the markers then occurred between 6 and 14 months of age. The timing of this increase was specific for each parameter. ICTP and OC concentrations increased between October and December. PICP concentrations increased between December and April whereas the increase in PIIINP was coincident with the peak in weight gain between April and June. Changes in BAP concentration were less distinct at this time. Season was shown to have significant effects on the biochemical markers independent from the effect of age. Concentrations of all markers decreased with increasing body weight and at any given age heavier horses had lower marker levels. These results show that biochemical markers of bone cell activity and soft tissue turnover follow characteristic patterns of change in growing thoroughbreds influenced by age, season and bodyweight. The demonstration that the reference ranges for the biochemical markers change from month to month means that single samples from individuals are of little value for monitoring bone cell activity in growing thoroughbreds.

Alkaline Phosphatase↗
PubMed1994

Investigation of association between alpha-1 proteinase inhibitor haplotype and endometritis in the thoroughbred mare.

Failure to inhibit proteinases can lead to excessive tissue damage. The possibility that the severity of endometritis in Thoroughbred mares correlates with the haplotypes of plasma alpha 1-proteinase inhibitor (alpha 1-PI) expressed was investigated in two groups of mares. In mares with pyometritis before treatment, the frequency of the N haplotype, which is already high in the Thoroughbred population, was significantly increased when compared with that in a large published population. In mares with acute endometritis which persisted after treatment followed by sexual rest, the absence of S and T haplotypes was significant, suggesting that, when present, they may have a protective function.

Alleles↗
PubMed1991

Failure of passive transfer of colostral immunity in the foal: incidence, and the effect of stud management and plasma transfusions.

The importance of colostrum for the passive transfer of maternal immunity to foals is well recognised. This survey reports the incidence of the failure of passive transfer of colostral immunity in thoroughbred foals in the United Kingdom during 1988 to 1990, and the effect of plasma transfusions on IgG levels in a group of them. The incidence of disease in these foals first month of life is also recorded.

Animals↗
PubMed1991

Assessment of the breeding prognosis of mares using paired endometrial biopsy techniques.

Paired endometrial biopsy samples were taken from 530 subfertile mares, before and after treatment (where indicated) and a period of sexual rest. Prognoses were made after each biopsy (Categories 1A-4A before treatment and Categories 1B-4B after treatment), using histopathological criteria similar to those described by Kenney and Doig (1986). Eighty-seven per cent of the mares were assigned to first biopsy prognosis Category 3A. The second biopsy prognosis produced a more even population distribution (10, 47, 40 and 3 per cent respectively for Category 1B, 2B, 3B and 4B mares). First biopsy Category 3A and 4A mares produced mean foaling rates of 51 and 40 per cent respectively. None of the 14 second biopsy Category 4B mares delivered a live foal (12 were barren, one aborted and one suffered early foetal death). This study supports the hypothesis that a breeding prognosis assigned on the basis of two endometrial biopsy samples, taken before and after specific uterine treatment, where indicated, which takes into consideration the mare's ability to respond to treatment, is likely to be more accurate than one assigned after a single biopsy sample.

Animals↗
PubMed1991

The effect of age and parity on the development of equine chronic endometrial disease.

The results of a retrospective analysis of 3,804 endometrial biopsy specimens collected from non-pregnant mares during the course of routine equine stud farm practice demonstrates a significant and practically useful correlation between the severity of chronic degenerative endometrial disease (CDE) diagnosed and age of mare at the time of examination. There were significant correlations between the number of foals born and the mares' barren years prior to biopsy and the severity of CDE, but the differences were not sufficiently large to be useful. Correlations between the severity of chronic infiltrative endometritis (CIE) and age or pre-biopsy parity were minimal. The results suggest that using similar histopathological criteria to those used by Kenney and Doig (1986), mares up to nine years of age should have no signs of CDE, mares up to 13 years of age should have no more than mild signs, mares up to 15 years of age should have no more than moderate signs and mares aged 17 years or older are likely to have severe signs. We believe that these guidelines are a useful, objective aid for formulating a breeding prognosis.

Age Factors↗
PubMed1991

The placenta as a determinant of fetal well-being in normal and abnormal equine pregnancies.

One hundred twenty-four horse placentas were evaluated according to gross appearance, weight and surface area. Grossly abnormal placentas were photographed, and histological sections were taken from abnormal appearing areas, and from representative areas (pregnant horn, non-pregnant horn, body and cervical pole) in both normal and abnormal placentas. Information about the resulting foals was obtained and correlations examined. Histological sections were reviewed and related to the resulting foals. Four normal fresh placentas were infused with dyes to ascertain the blood supply to various areas. Foal weight was statistically related to both allantochorionic surface area and allantochorionic weight. When normal placental surface area was divided by foal weight and related to gestational age, a statistical (P less than 0.0001 and r = 0.829) relationship emerged. Long cords were seen frequently with fetal demise. Histological abnormalities in the placenta were highly associated with fetal demise or fetal abnormalities, with only 2 normal Thoroughbred foals resulted from the 23 placentas exhibiting abnormal histology. Among the ponies, the same relationship held, with 3 normal ponies delivered from 9 abnormal placentas. Normal placentas were associated with normal offspring in most cases. Perfusion studies indicated that, in the four placentas studied, one umbilical artery supplied the cervical area and the non-pregnant horn, whereas the other supplied the pregnant horn. The body had a mixed supply from both arteries. This study evaluated the feto-placental unit in terms of normal and abnormal measurements and histology related to foal outcome. The presence of abnormal histological appearance of the placenta appeared to be more closely associated with foal abnormality than the percentage of placental area involved in the abnormal process. More information is needed before placental blood supply can be related to abnormal processes.

Animals↗
PubMed1987

The laboratory as an aid to clinical diagnosis.

The clinician may use the clinical pathology laboratory as a valuable aid to diagnosis and management, for the assessment of response to treatment, and in preventive medicine programs. Each "link in the chain," that is, sample selection, collection, handling, analysis, result reporting, and interpretation must be carefully and efficiently managed, using an informed combination of art and science, to provide a useful endpoint. This general introduction precedes more specific and detailed articles.

Animals↗
PubMed1987

Concentrations of uterine luminal prostaglandins in mares with acute and persistent endometritis.

Intrauterine infusion of 1 per cent oyster glycogen solution was used to induce acute endometritis in four genitally normal mares. Numbers of viable neutrophils recovered in uterine washings had increased by 1 h after infusion and remained elevated for at least 72 h. There was a significant correlation between numbers of viable neutrophils and total protein concentrations and between prostaglandin (PG)F and PGE2 concentrations in washings. There was also a significant relationship between concentrations of 15-keto-13, 14-dihydro PGF2 alpha in plasma and PGF in washings. Intrauterine concentrations of PGF were influenced by cycle stage and in turn the induced acute endometritis interfered with normal ovarian function. Mares with persistent endometritis had significantly higher concentrations of PGF and total protein and percentage of neutrophils and mononuclear cells in washings than normal mares. White blood cells from mares were capable of producing PGF and PGE2 in vitro.

Acute Disease↗