Growth factors are naturally occurring proteins or peptides that play a significant role in regulating cellular growth, proliferation, and differentiation in horses. These factors are involved in various physiological processes, including tissue repair, development, and immune function. Common growth factors studied in equine research include insulin-like growth factor (IGF), transforming growth factor-beta (TGF-β), and fibroblast growth factor (FGF). Their expression and activity can influence wound healing, musculoskeletal development, and recovery from injury. This page compiles peer-reviewed research studies and scholarly articles that examine the role, regulation, and clinical significance of growth factors in equine biology and health.
Valette JP, Robert C, Denoix JM.The objectives of this study were to establish standards for growth and to model the evolution of wither height (WH) between birth and adult age in different breeds of sport- and race-horses. Therefore, 398 foals, then yearlings of three different breeds, were measured regularly between birth and 18 months of age. Linear and non-linear functions were compared for describing the growth in each breed group. The monomolecular, Gompertz, logistic and cubic models correctly estimated WH in the three breeds during the first 2 years (R2 = 0.99, s.e. 3.9 to 4.5) and better than the cubic and quadratic...
Fortier LA, Smith RK.After tendon injury, the scar tissue that replaces the damaged tendon results in a substantial risk for reinjury. The goal of regenerative therapies is to restore normal structural architecture and biomechanical function to an injured tissue. Successful restoration processes for any tissue are thought to recapitulate those of development, in which there are spatial and temporal interactions between scaffold, growth factors, and cell populations.
Moffat PA, Firth EC, Rogers CW, Smith RK, Barneveld A, Goodship AE, Kawcak CE, McIlwraith CW, van Weeren PR.Conditioning by early training may influence the composition of certain musculoskeletal tissues, but very few data exist on its effect during growth on tendon structure and function. Objective: To investigate whether conditioning exercise in young foals would lead to any ultrasonographically detectable damage to the superficial digital flexor tendon or an increase in cross-sectional area (CSA). Methods: Thirty-three Thoroughbred foals reared at pasture were allocated to 2 groups: control (PASTEX) allowed exercise freely at pasture; and CONDEX, also at pasture, began conditioning exercise from ...
Morel PC, Bokor A, Rogers CW, Firth EC.To mathematically describe the growth of a population of Thoroughbred foals reared on pasture in New Zealand from birth to weaning. Methods: Twice-monthly liveweight data (including birthweight; BW) from 218 foals (98 colts and 120 fillies) born over a 6-year period, and reared on four different pasture types, were available for analysis. Data truncated to the time of weaning (107-217 days old) provided 3,200 data points. After testing for non-linearity of the relationship of age and liveweight (LW), five non-linear regression equations were tested for goodness of fit. Results: Colts and filli...
Allen WR, Gower S, Wilsher S.Polyclonal antisera for vascular endothelial growth factor (VEGF) and its two main receptor molecules, VEGF-I (Flt) and VEGF-II (KDR), were used in a conventional immunocytochemical staining method to localize these angiogenic ligand molecules in the endometrium and placenta of the mare during the oestrous cycle and pregnancy. The anti-VEGF and anti-Flt sera both labelled the lumenal and glandular epithelia of the endometrium throughout the oestrous cycle and both the invasive trophoblast cells of the endometrial cups and the non-invasive trophoblast of the allantochorion in pregnancy. The ant...
Stewart AA, Byron CR, Pondenis H, Stewart MC.To determine whether fibroblast growth factor-2 (FGF-2) treatment of equine mesenchymal stem cells (MSCs) during monolayer expansion enhances subsequent chondrogenesis in a 3-dimensional culture system. Methods: 6 healthy horses, 6 months to 5 years of age. Methods: Bone marrow-derived MSCs were obtained from 6 horses. First-passage MSCs were seeded as monolayers at 10,000 cells/cm(2) and in medium containing 0, 1, 10, or 100 ng of FGF-2/mL. After 6 days, MSCs were transferred to pellet cultures (200,000 cells/pellet) and maintained in chondrogenic medium. Pellets were collected after 15 days....
Strand E, Braathen LC, Hellsten MC, Huse-Olsen L, Bjornsdottir S.The Icelandic horse is a pristine breed of horse which has a pure gene pool established more than a thousand years ago, and is approximately the same size as living and extinct wild breeds of horses. This study was performed to compare the length of the skeletal growth period of the "primitive" Icelandic horse relative to that reported for large horse breeds developed over the recent centuries. This information would provide practical guidance to owners and veterinarians as to when the skeleton is mature enough to commence training, and would be potentially interesting to those scientists inve...
Ytrehus B, Carlson CS, Ekman S.Osteochondrosis is a common and clinically important joint disorder that occurs in human beings and in multiple animal species, most commonly pigs, horses, and dogs. This disorder is defined as a focal disturbance of enchondral ossification and is regarded as having a multifactorial etiology, with no single factor accounting for all aspects of the disease. The most commonly cited etiologic factors are heredity, rapid growth, anatomic conformation, trauma, and dietary imbalances; however, only heredity and anatomic conformation are well supported by the scientific literature. The way in which t...
Goodrich LR, Hidaka C, Robbins PD, Evans CH, Nixon AJ.Gene therapy with insulin-like growth factor-1 (IGF-1) increases matrix production and enhances chondrocyte proliferation and survival in vitro. The purpose of this study was to determine whether arthroscopically-grafted chondrocytes genetically modified by an adenovirus vector encoding equine IGF-1 (AdIGF-1) would have a beneficial effect on cartilage healing in an equine femoropatellar joint model. A total of 16 horses underwent arthroscopic repair of a single 15 mm cartilage defect in each femoropatellar joint. One joint received 2 x 10(7) AdIGF-1 modified chondrocytes and the contralateral...
Morisset S, Frisbie DD, Robbins PD, Nixon AJ, McIlwraith CW.Repair of cartilage defects involves sequential participation of specific hormones and growth factors with potential impairment by inflammatory cytokines. We explored an in vivo gene therapy treatment to supply adenoviral vectors carrying the genes of interleukin-1 receptor antagonist protein (IL-1ra) and insulinlike growth factor-1 (IGF-1), hoping to enhance repair of full-thickness equine chondral defects treated with microfracture. We asked whether our treatment could (1) increase proteoglycan and Type II collagen content in the repair tissue, (2) improve the macroscopic and histomorphometr...
Porter RM, Akers RM, Howard RD, Forsten-Williams K.Alginate hydrogel culture has been shown to reestablish chondrocytic phenotype following monolayer expansion; however, previous studies have not adequately addressed how culture conditions affect the signaling systems responsible for chondrocyte metabolic activity. Here we investigate whether chondrocyte culture history influences the insulin-like growth factor-I (IGF-I) signaling system and its regulation by interleukin-1 (IL-1). Articular chondrocytes (ACs) from equine stifle joints were expanded by serial passage and were either encapsulated in alginate beads or maintained in monolayer cult...
Lindbloom SM, Farmerie TA, Clay CM, Seidel GE, Carnevale EM.Human chorionic gonadotropin (hCG) was administered to mares in estrus with large, dominant ovarian follicles to initiate follicular and oocyte maturation. Follicular contents were collected at 0, 2, 4 and 6 h after hCG. Epiregulin, amphiregulin and phosphodiesterase (PDE) mRNA contents of granulosa cells (PDE 4D) were determined by reverse transcription and real-time PCR; PDE 3A mRNA content of single oocytes was determined similarly. Copy numbers of mRNA did not increase for PDE 3A or 4D over the time interval studied. Amounts of epiregulin and amphiregulin mRNA were correlated (r=0.98) when...
Johannessen MK, Skretting G, Ytrehus B, Røed KH.Endochondral bone formation is an important process in development and growth of the skeleton; still many of the mechanisms of growth cartilage remain unknown. The aim of this study was to identify genes specifically expressed in growth cartilage by constructing a subtraction cDNA library of the articular-epiphyseal cartilage complex from neonatal foal. Two hundred and eighty-four differently expressed clones, representing five novel and 37 known genes, were detected by subtraction hybridization. The tissue specificity of these genes was verified by reverse Northern analysis, and tissue distri...
Lejeune JP, Franck T, Gangl M, Schneider N, Michaux C, Deby-Dupont G, Serteyn D.Degenerative osteoarthropathy resulting in a reduced active lifespan was observed in Ardenner horses. In the context of joint biology, insulin-like growth factor I (IGF-I) is a potential candidate to affect the anabolism of cartilage matrix molecules. A group of 30 Ardenner horses reared under standardized conditions from weaning were evaluated periodically from 15 to 28 months of age to detect the early manifestations of the disease. At the end of this period, horses were classified in two pathological groups related to the degree of interphalangeal degenerative osteoarthropathy based on clin...
Donadeu FX, Watson ED.The annual reproductive cycle in the horse involves a reduction in ovarian activity during short days. The absence of ovulatory activity during winter has important consequences for an equine industry eager to breed mares early during the year. The anovulatory season results from a reduction in the secretion of pituitary gonadotropin that is in turn triggered by the inhibitory effects of short photoperiod on the hypothalamus-pituitary axis. Recent studies have provided evidence that the response of the ovaries to endocrine stimuli during the anovulatory season is affected not only by circulati...
Southwood LL, Lindermann J, Zarucco L, Driessen B, Olander H, Habecker P, Birks EK, Frisbie DD.Growth factors (GF) are important for maintenance and repair of intestinal mucosal structure and function, but there have been no studies investigating growth factor (GF) or growth factor receptor (GF-R) mRNA expression in the intestine of horses with large colon volvulus (LCV). Objective: (1) To determine mRNA expression for epidermal growth factor (EGF), EGF receptor (EGF-R), insulin-like growth factor-I (IGF), IGF receptor (IGF-R), vascular endothelial growth factor (VEGF) and VEGF receptor (VEGF-R) in the intestine of horses with an LCV compared to normal intestine. (2) To measure the corr...
Schnabel LV, Mohammed HO, Miller BJ, McDermott WG, Jacobson MS, Santangelo KS, Fortier LA.Platelet rich plasma (PRP) has recently been investigated for use in tissue regeneration studies that seek to utilize the numerous growth factors released from platelet alpha-granules. This study examined gene expression patterns, DNA, and collagen content of equine flexor digitorum superficialis tendon (SDFT) explants cultured in media consisting of PRP and other blood products. Blood and bone marrow aspirate (BMA) were collected from horses and processed to obtain plasma, PRP, and platelet poor plasma (PPP). IGF-I, TGF-beta1, and PDGF-BB were quantified in all blood products using ELISA. Ten...
Haupt JL, Donnelly BP, Nixon AJ.To evaluate the effects of recombinant human platelet-derived growth factor-BB (rhPDGF-BB) on the metabolic function and morphologic features of equine superficial digital flexor tendon (SDFT) in explant culture. Animals-6 euthanized horses (2 to 5 years old). Methods: Forelimb SDFT explants were cultured for 6 days as untreated control specimens or treated with rhPDGF-BB (1, 10, 50, or 100 ng/mL of medium). Treatment effects on explant gene expression were evaluated via real-time PCR analysis of collagen type I, collagen type III, PDGF-A, and PDGF-B mRNA. Explants were assayed for total colla...
Saito S, Sawai K, Minamihashi A, Ugai H, Murata T, Yokoyama KK.We describe here the isolation and maintenance of pluripotent embryonic stem (ES) cells from equine blastocysts that have been frozen and thawed. Equine ES cells appear to maintain a normal diploid karyotype in culture. These cells express markers that are characteristic of mouse ES cells, namely, alkaline phosphatase, stage-specific-embryonic antigen 1, STAT3, and Oct4. We also describe protocols for the induction of differentiation in vitro to neural precursor cells in the presence of basic fibroblast growth factor (bFGF), epidermal growth factor, and platelet-derived growth factor and to he...
Dario C, Carnicella D, Dario M, Bufano G.A data set concerning 1,816 subjects entered in the Italian Horse Registry from 1925 to 2002 was analyzed to investigate the morphological evolution of the Murgese horse and to obtain useful elements to enhance breeding practices. Three basic body measurements (height at withers, chest girth, and cannon bone circumference) were considered for each subject. Heritabilities were calculated for each parameter to infer the growth and development traits of this breed. Over the past 20 years the Murgese horse has undergone considerable changes, passing from a typical mesomorphic structure (height at ...
Nogueira GP, Barnabe RC, Verreschi IT.We measured progesterone and estradiol levels from birth to the beginning of adult life in 10 Thoroughbred fillies from the Equilia Stud Farm in Avaré SP, Brasil. The animals were measured and weighed monthly for the determination of body development and of a possible correlation between the rate of weight and height gain and the onset of detectable sex hormone levels. Jugular blood was collected twice a week and stored at -20 degrees C until assay of progesterone by a solid phase RIA with a sensitivity of 0.32 nmol L and of estradiol by liquid phase RIA adapted to low levels (3.67 pmol L ). ...
Goodrich LR, Brower-Toland BD, Warnick L, Robbins PD, Evans CH, Nixon AJ.Insulin-like growth factor-I (IGF-I) is one of the most influential growth factors in cartilage repair. Maintenance of adequate IGF-I levels after articular repair procedures is complicated by the short biological half-life of IGF-I in vivo. This study investigated the potential for more prolonged IGF-I delivery through direct adenoviral mediated transduction of synovial tissues in the metacarpophalangeal (MCP) joints of horses. The use of a large animal model provided a structurally similar and metabolically relevant corollary to the human knee. The complete IGF-I coding sequence was packaged...
Gee EK, Firth EC, Morel PC, Fennessy PF, Grace ND, Mogg TD.To determine the influence of copper (Cu) supplementation by injection of mares in late gestation on the frequency and severity of osteochondrosis (OC) lesions in their foals at around 160 days of age. To determine if there was any influence of the concentration of Cu in the liver, growth rate, birthweight, weight at 160 days of age, fatness, sex, or year of birth of the foal on the frequency and severity of OC lesions. To determine the influence of dam's age, and sex and birthweight of the foal on the growth rate from birth to 160 days of age, and weight at 160 days of age. Methods: Thirty-th...
Ordakowski-Burk AL, Kronfeld DS, Williams CA, Gay LS, Sklan DJ.To identify changes in folate status of mares and foals during lactation and growth, respectively. Methods: 20 Thoroughbred mares and foals. Methods: Pregnant mares, and following foaling the same mares with their foals, were maintained on mixed grass-legume pasture and fed either a traditional dietary supplement rich in sugar and starch (SS) or a dietary supplement high in fat and fiber (FF). Blood samples were collected monthly from mares and foals up to 6 months after foaling. Total folate concentration in feed and forage was determined. Analyses of plasma folate, RBC folate, plasma homocys...
Grace ND, Gee EK, Firth EC, Shaw HL.To measure the nutritive value of pasture in terms of digestible energy intake (DEI) and dry matter (DM) digestibility, and to determine the effect of Ca, P, Cu, Zn, and Se supplementation on growth rate and degree of physeal swelling in Thoroughbred yearlings grazed on pasture. Methods: Fourteen yearling horses were randomly allocated to 1 of 2 groups and rotationally grazed on a ryegrass/white clover pasture for 7 months. One group was supplemented daily with a mineral mix. Liveweight changes were recorded at fortnightly intervals and pasture mineral composition determined at monthly interva...
Henson FM, Bowe EA, Davies ME.To identify the effect of fibroblastic growth factor-2 (FGF-2) on the intrinsic damage-repair response in articular cartilage in vitro. Methods: Articular equine cartilage explants, without subchondral bone, had a single impact load of 500 g applied from a height of 2.5 cm. Explants were then cultured in 0, 12, 25, 50 or 100 ng/ml FGF-2 for up to 28 days. Unimpacted discs served as controls for each time-point. Histological and immunohistochemical techniques were used to quantify and characterise the response of putative chondrocyte progenitor cells (CPC) to damage and FGF-2 treatment. Results...
Akens MK, Hurtig MB.Bovine articular cartilage is often used to study chondrocytes in vitro. It is difficult to correlate in vitro studies using bovine chondrocytes with in vivo studies using other species such as rabbits and sheep. The aim of this investigation was to study the effect of species, anatomical location and exogenous growth factors on chondrocyte proliferation in vitro. Methods: Equine (EQ), bovine (BO) and ovine (OV) articular chondrocytes from metacarpophalangeal (fetlock (F)), shoulder (S) and knee (K) joints were cultured in tissue culture flasks. Growth factors (rh-FGFb: 10 ng/ml; rh-TGFbeta: 5...
Ott EA, Brown MP, Roberts GD, Kivipelto J.Forty-four weanling horses were used in two experiments to evaluate the effect of starch intake on growth and skeletal development. In Exp. 1, the weanlings were fed either a grain-based, high-starch (31.1%, DM basis) concentrate or a by-product-based, low-starch (0.0%) concentrate with coastal bermudagrass (Cynodon dactylon) hay. Corn oil was used to equalize the energy concentration of the concentrates. The concentrate:hay ratio was 64:36 (as-fed basis), and intake was the same for both diets. Body weight gains were greater by the weanlings consuming the high-starch concentrate (0.81 vs. 0.6...
Spaas JH, Gomiero C, Broeckx SY, Van Hecke L, Maccatrozzo L, Martens A, Martinello T, Patruno M.Several cytokines and growth factors play an essential role in skin regeneration and epithelial-like stem cells (EpSCs) have beneficial effects on wound healing in horses. However, there are no reports available on the expression of these growth factors and cytokines after EpSC therapy. Methods: Wounds of 6 cm(2) were induced in the gluteus region of 6 horses and treated with (i) autologous EpSCs, (ii) allogeneic EpSCs, (iii) vehicle treatment or (iv) untreated control. Real time polymerase chain reaction was performed on tissue biopsies taken 1 and 5 weeks after these treatments to evaluate...
Lennard SN, Stewart F, Allen WR.Placentation in equids involves two types of trophoblast: a minor invasive component, the chorionic girdle, that gives rise to transient endocrine structures known as endometrial cups, and a major non-invasive component, the allantochorion, that forms the diffuse, microcotyledonary placenta. Growth factors are likely to be important in controlling these complex events at implantation and this study describes the use of in situ hybridization and northern blotting techniques to monitor expression of insulin-like growth factor II (IGF-II) in the fetus and placenta of the horse (Equus caballus), u...
LaVigne EK, Jones AK, Londoño AS, Schauer AS, Patterson DF, Nadeau JA, Reed SA.Success as equine athletes requires proper muscle growth in young horses. Muscle hypertrophy occurs through protein synthesis and the contribution of muscle satellite cells, which can be stimulated or inhibited by cytokines and growth factors present during exercise and growth. The hypotheses of this study were that 1) the LM area in young horses would increase over 1 yr, and 2) specific cytokines and growth factors (IL-1β, IL-6, tumor necrosis factor [TNF]-α, IGF-I, and fibroblast growth factor [FGF]-2) would alter proliferation and differentiation of satellite cells isolated from young hor...
Verwilghen DR, Vanderheyden L, Franck T, Busoni V, Enzerink E, Gangl M, Lejeune JP, van Galen G, Grulke S, Serteyn D.Developmental osteochondral lesions are often encountered in the equine population and are a major cause of lameness. Different growth factors that act systemically as well as locally regulate the growth of cartilage. Among them is Insulin-like Growth Factor I that has been demonstrated to promote chondrocyte growth and differentiation and that has been shown to influence cartilage repair. The aims of this study were to investigate differences in circulating plasma levels of Insulin-like Growth Factor-I in post-pubescent horses affected with developmental osteochondral lesions compared to unaf...
Morel PC, Bokor A, Rogers CW, Firth EC.To mathematically describe the growth of a population of Thoroughbred foals reared on pasture in New Zealand from birth to weaning. Methods: Twice-monthly liveweight data (including birthweight; BW) from 218 foals (98 colts and 120 fillies) born over a 6-year period, and reared on four different pasture types, were available for analysis. Data truncated to the time of weaning (107-217 days old) provided 3,200 data points. After testing for non-linearity of the relationship of age and liveweight (LW), five non-linear regression equations were tested for goodness of fit. Results: Colts and filli...
Back W, Schamhardt HC, Hartman W, Bruin G, Barneveld A.The gait of 24 horses was recorded on a treadmill when they were trotting at 4 m sec-1, first when they were four months old and again when they were 26 months. The data recorded at four months were used to predict the locomotion of the adult horses, and the predictions were assessed against the data recorded at 26 months. The locomotion of the foals and the adults appeared to be closely related, when the differences in segment length and joint angles due to growth were taken into account. The duration of swing, the total range of protraction and retraction, and the maximum tarsal flexion coul...
Graham PM, Ott EA, Brendemuhl JH, TenBroeck SH.Thirty-nine Thoroughbred and Quarter Horse yearlings were used in two 112-d experiments to determine the effect of lysine and threonine supplementation on growth and development. Yearlings were individually fed three dietary treatments that consisted of a pelleted concentrate containing corn, oats, and soybean meal fed to appetite twice daily and Coastal bermuda grass hay group-fed at a rate of 1 kg/100 kg BW. Three concentrates were tested: (A) basal, (B) basal plus .2% lysine, and (C) basal plus .2% lysine, and .1% threonine. Feed intake, weight, withers height, girth, hip height, body lengt...
Gunn HM.The numbers of fibres in the complete cross section of the semitendinosus were estimated in 58 equines and 59 canines of differing types. Animals selected for swiftness--thoroughbred horses and greyhounds--have a greater number of fibres in a cross section of their semitendinosus than other members of their species, whether as neonates or as adults. The numbers of fibres in the cross section increases during growth in both types of animal in each species.
Porter RM, Akers RM, Howard RD, Forsten-Williams K.Alginate hydrogel culture has been shown to reestablish chondrocytic phenotype following monolayer expansion; however, previous studies have not adequately addressed how culture conditions affect the signaling systems responsible for chondrocyte metabolic activity. Here we investigate whether chondrocyte culture history influences the insulin-like growth factor-I (IGF-I) signaling system and its regulation by interleukin-1 (IL-1). Articular chondrocytes (ACs) from equine stifle joints were expanded by serial passage and were either encapsulated in alginate beads or maintained in monolayer cult...
Ginther OJ, Gastal EL, Gastal MO, Beg MA.During a follicular wave in mares, the two largest follicles (F1 and F2) begin to deviate in diameter when F1 is a mean of 22.5 mm. The intrafollicular effects of pregnancy-associated plasma protein-A (PAPP-A), IGF-I, activin-A and vascular endothelial growth factor (VEGF) on other follicular-fluid factors during deviation were studied. In four treated groups (n = 7/group), a single dose of one of the four factors was injected into F2 when F1 was > or = 20.0 mm (expected beginning of deviation). In a control group (n = 7), F2 was injected with vehicle. One day after treatment, a sample of f...
Martoriati A, Duchamp G, Gérard N.Paracrine factors have significant effects during folliculogenesis. Because of various morphological features, the mare is a convenient model to study in vivo the effects of factors involved in periovulatory events. In the present work, epidermal growth factor (EGF; experiment 1, n = 49 mares) and interleukin-1beta and interleukin-1RA (IL-1beta and IL-1RA, respectively; experiment 2, n = 80 mares) were injected intrafollicularly to evaluate the influence of these factors on in vivo maturation of equine preovulatory follicles. A transvaginal ultrasound-guided injection was performed when the di...
Yoon MJ, Roser JF.Localization of IGF-I and IGF-IR were observed in Leydig cells of horses using immunohistochemistry (IHC), suggesting IGF-I may play a role in equine Leydig cell steroidogenesis. Previous studies in other species have indicated that IGF-I increases basal and/or LH/hCG-induced testosterone production. The objectives of this study were to (1) test the synergistic effect of IGF-I on eLH-induced testosterone production in cultured equine Leydig cells and (2) determine if this effect is reproductive stage-dependent. Testes were collected from five pubertal (1.1±0.1 year; 1-1.5 year) and eight post...
Milner PI, Smith HC, Robinson R, Wilkins RJ, Gibson JS.Hypoxia and acidosis are recognized features of inflammatory arthroses. This study describes the effects of IGF-1 and TGF-β(1) on pH regulatory mechanisms in articular cartilage under hypoxic conditions. Acid efflux, reactive oxygen species (ROS), and mitochondrial membrane potential were measured in equine articular chondrocytes isolated in the presence of serum (10% fetal calf serum), IGF-1 (1, 10, 50, 100 ng/ml) or TGF-β(1) (0.1, 1, 10 ng/ml) and then exposed to a short-term (3 h) hypoxic insult (1% O(2)). Serum and 100 ng/ml IGF-1 but not TGF-β(1) attenuated hypoxic regulation of pH hom...
Packard GC.I re-examined published data for ontogenetic change in relative mass of the brain in six species of mammal (i.e., sheep, pig, cow, horse, rat, cat) to illustrate an insidious problem with conventional analyses of brain-body allometry. Graphical displays of logarithmic transformations of the original data for each species give the appearance of two discrete mathematical distributions, but untransformed observations nonetheless conform to a single distribution that is well described by a single, nonlinear equation. The concept of biphasic, allometric growth by the brain consequently is an artifa...
Cochrane CA, Freeman KL, Knottenbelt DC.Wound healing in equidae is delayed and more complicated than in other species. These complications arise from a condition known as exuberant granulation tissue formation. The lower limb of the horse is frequently slower to heal than other parts of the body and has a particular tendency to produce excess (exuberant) granulation tissue. Sarcoids are tumor-like lesions of the skin which often appear at the site of wounds. This study compared the growth characteristics of the sarcoid and granulation tissue-derived cells with normal dermal fibroblasts grown from primary cell cultures. All three ce...
Staniar WB, Kronfeld DS, Hoffman RM, Wilson JA, Harris PA.Monitoring weight of foals is a useful management practice to aid in maximising athletic potential while minimising risks associated with deviations from normal growth. Objective: To develop predictive equations for weight, based on linear measurements of growing Thoroughbreds (TBs). Methods: Morphometric equations predicting weight from measurements of the trunk and legs were developed from data of 153 foals. The accuracy, precision and bias of the best fitting equation were compared to published equations using a naive data set of 22 foals. Results: Accuracy and precision were maximised with...
Garbin LC, Contino EK, Olver CS, Frisbie DD.Hemoderivatives such as autologous conditioned serum (ACS) and platelet-rich plasma (PRP) have been used as potential disease-modifying therapies in musculoskeletal disorders such as osteoarthritis (OA). These therapies are based on the delivery of multiple growth factors and anti-inflammatory cytokines that are known to participate in inflammatory processes. The variability of cytokine content due to the autologous nature of the product, the non-availability for immediate use and need for storage at low temperatures are limitations for its use in the field. An allogeneic freeze-dried conditio...
Koterba AM, Wozniak JA, Kosch PC.The purpose of the study was to document the developmental changes in the ventilatory and timing parameters associated with quiet breathing at rest in awake, standing horses during the first year post partum. Tidal volume (VT), breathing frequency, airflow, mechanical timing intervals and minute ventilation (VE) were measured serially in foals age 24 h-1 year. In the growing foal, VE increased due to a progressive rise in VT, in spite of a pronounced decrease in respiratory frequency. When normalised to body weight (bwt), VE/kg declined with maturation in a curvilinear fashion, from mean +/- s...
Green DA.One hundred and four animals aged 13-18 months were measured at monthly or two monthly intervals, as were comparable numbers of animals 19-36 months old. Height, girth and circumference of the cannon bone below the knee were recorded, measurements for colts and fillies are shown separately. The average height at 18 months was 148 cm (15.01/2 h.h.) and at 36 months 156 cm (15.31/2 h.h.).
Ollivier FJ, Brooks DE, Schultz GS, Blalock TD, Andrew SE, Komaromy AM, Cutler TJ, Lassaline ME, Kallberg ME, Van Setten GB.Healing of corneal ulcers in horses is often associated with profound corneal stromal fibrosis and scar formation resulting in visual impairment. Connective tissue growth factor (CTGF) is a fibrogenic cytokine involved in wound healing and scarring. The purpose of this study was to determine whether CTGF was present in the tear fluid of normal horse eyes and the eyes of horses with corneal ulcers in order to evaluate the role of CTGF in corneal wound healing and corneal scar formation. Methods: Tear fluid samples were collected from 65 eyes of 44 horses; 32 samples from normal eyes, 21 samples...
Hess-Dudan F, Vacher PY, Bruckmaier RM, Weishaupt MA, Burger D, Blum JW.Concentration of (total) globulin was relatively stable in blood plasma of mares, but rapidly decreased in colostrum to very low levels within 2 days after parturition. In foals, after intake of the first colostrum, globulin increased within 1 day in blood plasma, but remained at lower concentrations than those measured in mare plasma. Concentrations of immunoreactive insulin (iI) were high during the first 2 months of lactation in blood plasma of mares and then decreased, were high in first colostrum and then decreased drastically, and remained at low concentrations up to weaning in blood of ...
Fukuda K, Kuwano A, Kuroda T, Tamura N, Mita H, Okada Y, Kasashima Y.This study optimized the double-spin conditions for preparing equine platelet-rich plasma (PRP): leukocyte-rich PRP (L-PRP) and leukocyte-poor PRP (P-PRP). Whole blood samples were centrifuged at various double-spin conditions. Both L-PRP and P-PRP were prepared at each stage, and complete blood counts and growth factor concentrations were compared. Samples centrifuged at 160 × 900 g, 160 × 2,000 g, and 400 × 2,000 g exhibited the highest platelet counts. P-PRP had significantly lower leukocyte and erythrocyte contents than L-PRP, especially at 400 × 2,000 g. No significant differences wer...
Carson K, Wood-Gush DG.Thoroughbred foals were found to nurse in bouts of nursing activity delimited by intervals of non-nursing activity lasting 27 secs or longer. Nursing activity included nosing, sucking and interval behaviour. During the first week after birth, foals nursed, on average, seven times an hour with a mean bout duration of 147 secs but were not successful at sucking during all nursing bouts. Time spent nursing decreased as the foals grew older until before weaning, at 24 weeks of age, the foals were nursing once an hour with a mean bout duration of 74 secs. The dams hindered their foals' nursing acti...
Winsco KN, Coverdale JA, Wickersham TA, Shelton JL.Twenty-four Quarter Horse weanlings (120 ± 10 d) were blocked by age into 4 groups (n=6) for a 56-d trial to evaluate the influence of dietary Met concentration on growth and N balance. Weanling horses were housed by block and individually fed concentrates twice daily at 1.75% BW (as-fed basis). Weanling horses were randomly assigned to 1 of 4 concentrate treatments: basal (0.20 Met), basal + 0.03% Met (0.23 Met), basal + 0.07% Met (0.27 Met), and basal + 0.11% Met (0.31 Met). Diets were formulated to be isonitrogenous and isocaloric and contained equal amounts of Lys and Thr. Coastal bermuda...
Wilson RT.Equines have been largely ignored in modern scientific literature on domestic animals, probably because they are not providers of meat and milk. Their contribution to the economy in the Sudan, however, is considerable and they are the principal means of transport both as baggage and as riding animals. They also play an important role in the supply of fuel and the distribution of domestic water in the larger villages and towns. Information on population structure is provided and descriptions, with particular reference to withers height and weight, are given of two types of donkey and of the hor...
Carnevale EM, Coutinho da Silva MA, Maclellan LJ, Seidel GE, Squires EL.Parentage identification was used to test the developmental competence of oocytes cultured under different conditions and fertilized in vivo after oocyte transfer. Oocytes were collected transvaginally from follicles of estrous mares approximately 22 h after administration of human chorionic gonadotropin. Oocytes were cultured for approximately 16 h in one of three media, with or without addition of hormones and growth factors. Groups of three or four oocytes, cultured in different media, were transferred into the oviduct contralateral to a recipient's own ovulation. Recipients were inseminate...
Ott EA, Asquith RL.Forty-six Thoroughbred and Quarter Horse yearlings were used in two experiments to evaluate the effect of mineral supplementation on growth and skeletal development. In the first experiment, concentrate and bermuda-grass hay diets providing 2.82 Mcal DE/kg (estimated), 13.0% CP, .62% Ca and .43% P on a DM basis were supplemented with trace minerals (TM) by adding 0, .5 or 1.0% TM premix to the concentrate. The TM content of the three diets (concentrate and hay) in mg/kg DM were: Fe 150, 162 and 176; Mn 56, 60 and 64; Zn 36, 53 and 69; and Cu 7, 8 and 11 for the low, medium and high TM levels, ...
Goudet G, Belin F, Młodawska W, Bézard J.The effect of epidermal growth factor (EGF) on the in vitro maturation rate of equine oocytes was examined. Oocytes were collected from an abattoir (Expt 1) or using ultrasound-guided follicular puncture in vivo (Expt 2). All oocytes with a compact or expanded cumulus at recovery were cultured for 30 h in: medium 1 (TCM199 + fetal calf serum (FCS) + crude equine gonadotrophin (CEG) + oestradiol + antibiotics); medium 2 (TCM199 + EGF); medium 3 (medium 1 without FCS + EGF); or medium 4 (medium 1 without CEG + EGF). In Expt 1, 84% (37/44) and 87% (40/46) cumulus expansion (P > 0.05), and 39% (22...
