Stereotypic behavior in horses refers to repetitive, invariant actions with no apparent function or goal, often observed in domesticated equines. These behaviors can include cribbing, weaving, and stall walking, among others. Stereotypic behaviors are generally considered indicators of suboptimal environmental conditions or stress and are of interest in equine welfare studies. This page compiles peer-reviewed research studies and scholarly articles that explore the prevalence, potential causes, and management strategies for stereotypic behaviors in horses, as well as their implications for equine welfare and management practices.
McClure SR, Chaffin MK, Beaver BV.Self-mutilative behavior, a form of stereotypic behavior, can be a serious problem in stallion management. An 11-year-old Quarter Horse stallion was referred for evaluation of repeated episodes of self-mutilation and aggressive behavior. Historically, this behavior worsened when the horse was isolated from other animals and confined to a stall for long periods. Observations of the stallion revealed episodes of self-mutilation and other forms of stereotypic behavior precipitated by stressful situations. Modification of this behavior was achieved by environmental and nutritional management and p...
Sambraus HH, Radtke K.Studies were made on 27 horses which were known to weave. They were stallions, mares and geldings between the ages of 3 and 22 years. The horses were individually observed for several days in their habitual surroundings. A period, in which a horse makes pauses of not more than ten minutes, is considered a weaving phase. Shorter pauses subdivide the weaving phase into weaving series. The basic unit of weaving is the weaving displacement, i.e. the head movement between the turning points. The number of daily weaving displacements of the horses examined varied from less than 400 up to almost 18,0...
Green P, Tong JM.Although wood chewing by horses is recognised as a common vice, there are few reports of specific disease associated with the habit. Two cases of acute obstruction of the small intestine by solid aggregations of wood splinters are described in horses which were both habitual wood chewers. Details are presented of the clinical findings in these cases, including the surgical treatment of acute colic. Both horses returned to full working fitness. The authors review the syndrome of enterolithiasis in horses, and discuss the causes and significance of wood chewing as a stable vice.
Dodman NH, Shuster L, Court MH, Dixon R.Crib-biting in horses is a repetitive behavior pattern which may involve the activation of both narcotic receptors and dopamine receptors in the CNS. Crib-biting frequency, determined in 7 nontreated horses under controlled conditions, was usually linear for many hours and ranged from 0.3 to 14.9 bites/min. Intravenous or IM injections of narcotic antagonists decreased these rates to almost zero by about 20 minutes after the injection was given. The duration of the response to a single injection ranged from 20 minutes for naloxone to 4 hours or more for nalmefene and diprenorphine. Effective d...
Numazawa M, Osawa Y.The metabolic pathway leading to equilin and equilenin biosynthesis in the pregnant mare is different from that of estrone and estradiol and it is apparently cholesterol-independent. The precise precursors and intermediates and the stereomechanism of equine placental aromatization have not been established. [1,2-3H, 4-14C]3-Hydroxy-3,5,7-androstatrien-17-one was synthesized as a potential substrate and the 3H-distribution was analyzed by biochemical and chemical derivatization methods. The substrate was converted to equilin, equilenin and Heard's ketone by horse placental microsomes with a sp....
Turner AS, White N, Ismay J.Thirty-five horses with a history of crib biting or wind sucking were treated with a modification of the Forssell procedure. The technique involved bilateral neurectomy of the ventral branch of the accessory nerve combined with excision of a portion of the omohyoideus, sternohyoideus, and sternothyroideus muscles. Twenty horses became free of the vice, while in 11 there was a noticeable reduction in frequency of the vice. Four horses returned to crib biting/wind sucking at the same intensity as before surgery. The observation time following each operation was at least 12 months. Complications ...
Firth EC.Bilateral neurectomy of the ventral branch of the spinal accessory nerve was performed in an attempt to control windsuckling. There was no permanent improvement in the eight cases described.
Houghton E.1. The metabolism of 19-nortestosterone in a cross-bred horse has been studied using 14C-labelled material. 2. Two neutral metabolites isolated from urinary extracts by column chromatography were identified as isomers of 3-hydroxyestran-17-one and estrane-3,17-diol by g.l.c.-mass spectrometry. 3. The stereochemistry of the two metabolites has been investigated by comparison of the retention times of their trimethylsilyl derivatives with those of standard steroids of known configuration.
Oh R, Tamaoki BI.The microsomal fraction (10 000–105 000 × g precipitate) of equine testes was fractionated into the smooth- and the rough-surfaced microsomal subfractions by a sucrose density-gradient centrifugation in the presence of CsCl. The validity of this fractionating procedure was confirmed by electron microscopic examination and also by chemical analysis of the RNA contents in these subfractions. The aromatizing enzyme system (19-hydroxylase and aromatase) which was concentrated in the microsomal fractions among the organellae was found to be localized in the smoothsurfaced microsomal fraction. Th...
Turner AS, White N, Ismay J.Thirty-five horses with a history of crib biting or wind sucking were treated with a modification of the Forssell procedure. The technique involved bilateral neurectomy of the ventral branch of the accessory nerve combined with excision of a portion of the omohyoideus, sternohyoideus, and sternothyroideus muscles. Twenty horses became free of the vice, while in 11 there was a noticeable reduction in frequency of the vice. Four horses returned to crib biting/wind sucking at the same intensity as before surgery. The observation time following each operation was at least 12 months. Complications ...
Albanese V, Munsterman AS, DeGraves FJ, Hanson RR.To measure intra-abdominal pressure (IAP) in horses that crib and compare it with IAP in horses that do not have this vice. Methods: Cohort study. Methods: Healthy cribbing horses (cribbing cohort, n = 8) and 8 healthy noncribbing horses (noncribbing cohort). Methods: A microsensor catheter was introduced into the peritoneal cavity through the right paralumbar fossa, using local anesthesia, for measurement of IAP. These pressures were recorded in 1-minute intervals for 2 hours, while the horses were standing tied in a stall. IAPs of cribbing horses were compared to the noncribbing cohort...
Bolat D, Yıldız D, Bahar S, Yürüker S, Kaymaz F, Ilgın C, Bozkurt EÜ, Karahan S, Sabancı SS.We investigated the microscopic structure of transverse sections of the oculomotor, trochlear and abducens nerves of Arabian foals using stereological methods. Bilateral nerve pairs from 2-month-old female Arabian foals were analyzed. The tissues were embedded in plastic blocks, then 1 µm thick sections were cut and stained with osmium tetroxide and methylene blue-azure II. Stereology was performed using light microscopy. Morphometry showed that the right and left pairs of nerves were similar. The transverse sectional areas of the oculomotor, trochlear and abducens nerves were 1.93 ± 0.19 mm...
Delacalle J, Burba DJ, Tetens J, Moore RM.To report an neodymium:yttrium-aluminum garnet (Nd:YAG) laser-assisted modified Forssell's surgical technique and outcome for treatment of cribbing (crib-biting) in horses. Methods: Retrospective clinical study. Methods: Ten adult horses with stereotypic cribbing behavior. Methods: Data were obtained from medical records and telephone conversations with owners, trainers, and veterinarians. Surgical technique involved an approximately 34-cm ventral median skin incision starting rostral to the larynx and extending caudally. A 10-cm section of the ventral branch of the spinal accessory nerve was ...
Albright JD, Witte TH, Rohrbach BW, Reed A, Houpt KA.Crib-biting is a common oral stereotypy. Although most treatments involve prevention, the efficacy of various anti-crib devices, including surgically implanted gingival rings, has thus far not been empirically tested. Objective: Demonstrate the effect that 2 anti-crib collars, muzzle and gingival rings have on crib-biting, other maintenance behaviours, and cortisol levels in established crib-biting horses. Methods: Randomised, crossover clinical trial. Methods: In Experiment I, 2 anti-crib collars and a muzzle were used on 8 established crib-biting horses; horses wore each of 3 devices for 7 d...
Mazzola S, Palestrini C, Cannas S, Fè E, Bagnato GL, Vigo D, Frank D, Minero M.Cribbing is an oral stereotypy, tends to develop in captive animals as a means to cope with stress, and may be indicative of reduced welfare. Highly energetic diets ingested in a short time are one of the most relevant risk factors for the development of cribbing. The aim of this study was to verify whether feeding cribbing horses through a dispenser that delivers small quantities of concentrate when activated by the animal decreases cribbing behaviour, modifies feeding behaviour, or induces frustration. Ten horses (mean age 14 y), balanced for sex, breed, and size (mean height 162 cm), we...
McClure SR, Chaffin MK, Beaver BV.Self-mutilative behavior, a form of stereotypic behavior, can be a serious problem in stallion management. An 11-year-old Quarter Horse stallion was referred for evaluation of repeated episodes of self-mutilation and aggressive behavior. Historically, this behavior worsened when the horse was isolated from other animals and confined to a stall for long periods. Observations of the stallion revealed episodes of self-mutilation and other forms of stereotypic behavior precipitated by stressful situations. Modification of this behavior was achieved by environmental and nutritional management and p...
Wickens C, Arias Esquivel AM, Hendricks C, Heleski C.Several studies have indicated higher incidence of stereotypic behaviors (STBs) in Thoroughbreds. The aftercare of Off-the-Track Thoroughbreds (OTTBs) has received increased attention in the last decade; however, research on the impact of STBs on placement of OTTBs after their racing career is limited. Thoroughbred Aftercare Alliance (TAA) accredits centers throughout North America that work to rehome OTTBs in a safe, welfare-friendly manner. Although the authors have suspected that having an STB would make OTTBs more challenging to rehome, this hypothesis remains to be empirically tested. The...
Schofield WL, Mulville JP.The modified Forssell's procedure was performed on 10 horses in an attempt to cure oral stereotypies. Three horses were cured completely, two horses were considerably improved, and five horses continued to perform the stereotypy after periods of remission ranging from two weeks to six months. This rate of success for the modified Forssell's procedure, as in other published reports, was lower than for the original Forssell's procedure. Surgery to eliminate a stereotypical behaviour pattern may exacerbate the stress for an animal and the modified Forssell's procedure can no longer be recommended...
Stange LM, Krieter J, Czycholl I.Equine headshaking syndrome (EHS) is characterised as non-physical and involuntary movement of the horse's head and neck. Although EHS is clinically simple to diagnose, its aetiopathogenesis often remains unclear. The aim of this study was to gain an overview of signalment and therapy possibilities used in France and Switzerland. To do this, an online survey was developed and distributed via newsletters. A total of 933 complete, answered surveys from France ( = 804) and Switzerland ( = 129) were evaluated. The median age in France was 12.4 years (CH = 14.3). Mostly geldings were affected (58.5...
Sambraus HH, Radtke K.Studies were made on 27 horses which were known to weave. They were stallions, mares and geldings between the ages of 3 and 22 years. The horses were individually observed for several days in their habitual surroundings. A period, in which a horse makes pauses of not more than ten minutes, is considered a weaving phase. Shorter pauses subdivide the weaving phase into weaving series. The basic unit of weaving is the weaving displacement, i.e. the head movement between the turning points. The number of daily weaving displacements of the horses examined varied from less than 400 up to almost 18,0...
McKinney AR, Suann CJ, Stenhouse AM.An investigation was conducted into the stereochemistry of the equine urinary metabolites of 17alpha-methyltestosterone observed after oral administration. Standards of the complete range of C3/C5/C16 stereoisomeric 17alpha-methylandrostane-3,17beta-diols, 17alpha-methylandrostane-3,16,17beta-triols and 17alpha-hydroxymethylandrostane-3,17beta-diols were purchased or synthesised, and were used to unequivocally identify the absolute structures of the metabolites. Phase I metabolism was found to involve combinations of Delta(4)-3-ketone reduction with both 5alpha,3beta- and 5beta,3alpha-stereoch...
Oh R, Tamaoki BI.The microsomal fraction (10 000–105 000 × g precipitate) of equine testes was fractionated into the smooth- and the rough-surfaced microsomal subfractions by a sucrose density-gradient centrifugation in the presence of CsCl. The validity of this fractionating procedure was confirmed by electron microscopic examination and also by chemical analysis of the RNA contents in these subfractions. The aromatizing enzyme system (19-hydroxylase and aromatase) which was concentrated in the microsomal fractions among the organellae was found to be localized in the smoothsurfaced microsomal fraction. Th...
