Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Stallion
Stallions are adult male horses that have not been gelded and are often used for breeding purposes. They exhibit distinct behavioral and physiological characteristics compared to mares and geldings. Stallions are known for their strong musculature, prominent neck, and often more pronounced mane and tail. Their behavior can be more aggressive and territorial, especially during the breeding season, as they naturally compete for mating opportunities. This topic explores the anatomy, behavior, and management practices specific to stallions, as well as their role in equine reproduction. The page provides access to peer-reviewed research studies and scholarly articles that investigate various aspects of stallion health, fertility, and behavior, contributing to the understanding and management of these horses in equine science.
Observational study of “urine testing” in the horse and donkey stallion. Although "urine testing" is said to enable the male equid to assess the sexual status of the mare, there are no reports in the literature of any detailed study of this behavioural response of the stallion. Behavioural response to conspecific urine was studied in two horse stallions and one donkey stallion. The relevant nasopalatine anatomy is described. Events observed during urine testing included head, neck, lip, jaw, tongue movements, penile changes and nasal secretion. Nasal endoscopy indicated that the source of part of the nasal secretion was the secretory glands of the vomeronasal organ...
Experimental production of neonatal isoerythrolysis in the foal. Serological evidence with or without clinical signs of neonatal isoerythrolysis was experimentally produced in 6 of 8 foals born to mares allo-immunized with washed erythrocytes from the stallion. Blood group antigens were determined in all mares, stallions and foals, and the incompatible antigenic factor(s) responsible for the disease were defined. In 5 of 8 foals born to alloimmunized mares, a single antigenic factor difference accounted for the erythrocyte incompatibility between mare and foal. The erythrocyte antigen suspected as the most responsible for isoerythrolysis observed was A1. Ag...
Induction of male sex behavior in pony mares with testosterone propionate. Two pony mares were administered 150 mg of testosterone propionate every other day for 20 days (ten injections) and every ten days there-after. An additional two mares and one stallion were not treated and served as controls. Testosterone propionate was dissolved in absolute ethanol and administered subcutaneously. Sex behavior tests were conducted 26 and 40 days after the first injection. Control mares exhibited very little male sex behavior. Both testosterone propionatetreated mares, however, exhibited mounting, sniffing, flehmen, biting and vocalization behavior in the presence of an estrou...
Age-related and seasonal variation in the Sertoli cell population, daily sperm production and serum concentrations of follicle-stimulating hormone, luteinizing hormone and testosterone in stallions. Testes and blood samples were obtained from 201 stallions aged 6 months to 20 years in either December-January (nonbreeding season) or June-July (breeding season) to study the effect of age and season on reproductive parameters. Seasonal differences in the Sertoli cell population of adult (4-20 years old) horses were characterized by a 36% larger number of Sertoli cells in the breeding season than in the nonbreeding season. Seasonal elevation in the Sertoli cell population was associated with an increase in testicular weight and daily sperm production per testis (DSP/testis). Concentrations of...
[Experiences with half-closed castration in stallions]. The half-closed method of castration involves ligation of the spermatic cord enclosed in the vaginal tunic, the testicle itself lying outside the opened vaginal tunic. Of 497 horses and ponies admitted to the Department of Large Animal Surgery and castrated using this technique, 68.6 per cent recovered without complications. Although the most serious postoperative complications such as intestinal eventration and haemorrhage of the spermatic cord may be reduced to a minimum by this approach, normal healing cannot be guaranteed under the circumstances in which this method was used.
[Primary closure of the scrotal wound in the castration of stallions]. A method of castration in stallions is reported on, in which primary closure of the wound caused by castration was attempted. Primary wound-healing occurred in 90 per cent of 110 stallions showing normally descended testicles, whereas this proportion was 97.4 per cent in thirty-eight unilaterally cryptorchid stallions in which the normally descended testicle was removed using the method described. It is concluded that the present method of castration will only be successful when surgery is carried out under strictly aseptic conditions.
[An inventory of the castration of stallions based on a survey among Dutch veterinarians]. To gain an insight into the procedures adopted in castrating stallions in the Netherlands, a questionnaire was sent to 670 Dutch veterinary practitioners. The 176 veterinary practitioners who replied performed 1850 castrations. Castration of the recumbent horse was preferred by 88 per cent of the veterinary surgeons. Fifty per cent preferred the open method of castration and 44 per cent the half-closed technique. A local anaesthetic was given by 65 per cent of the practitioners; 84 per cent administered antibiotics in an attempt to prevent wound infection. Postoperative complications were obse...
Pregnancy rates and sexual behavior under pasture breeding conditions in mares. Pony mares (n=480) and 16 stallions were assigned to four herds of 60 mares and one stallion (large herds) and to 12 herds of 20 mares and one stallion (small herds). The stallions remained with the herds continuously for all of the large herds and seven of the small herds. In the five remaining small herds the stallion was put into a herd for three hours every two days for 12 observation periods. Pregnancy rates and day of ovulation were estimated by size of embryonal enlargements. Mean pregnancy rates of 51% and 54% were obtained in the small herds and 42% in the large herds during a 48-day ...
Inhibition of motility of bovine, canine and equine spermatozoa by artificial vagina lubricants. The effects of four vaginal lubricants on progressive spermatozoal motility were evaluated. Neat semen was exposed to 0, 5, or 10% (w/v) of H-R, sterile K-Y, nonsterile K-Y or Maxilube lubricating jellies for 10 min at 37 degrees C and then extended to 10x10(6) spermatozoa/ml. Spermatozoal motility was evaluated after 0, 1, 2, 4 and 6 or 8 h of incubation at 37 degrees C. For bovine spermatozoa, sterile K-Y jelly at 10% suppressed motility (P<0.05), but nonsterile K-Y, H-R and Maxilube jellies had no effect. Maxilube was toxic (P<0.01) to canine spermatozoa and is not recommended for use...
The effects of stanozolol and boldenone undecylenate on scrotal width, testis weight, and sperm production in pony stallions. Fifty mature pony stallions were randomly assigned to one of five treatment groups: Group 1- controls (no treatment), Group 2 - 0.55 mg/kg stanozolol weekly for 13 treatments, Group 3 - 1.1 mg/kg stanozolol every 3 weeks for 5 treatments, Group 4 - 1.1 mg/kg boldenone undecylenate every 3 weeks for 5 treatments, and Group 5 - 0.55 mg/kg boldenone undecylenate weekly for 13 treatments. Scrotal widths (SW), combined testis weights (CTW), and daily sperm productions (DSP) were not different between Groups 1 and 2. Ponies in Group 5 had smaller SW (P<0.01), smaller CTW and decreased DSP compare...
Induced abortion and social factors in wild horses. Much evidence now suggests that the postnatal killing of young in primates and carnivores, and induced abortions in some rodents, are evolved traits exerting strong selective pressures on adult male and female behaviour. Among ungulates it is perplexing that either no species have developed convergent tactics or that these behaviours are not reported, especially as ungulates have social systems similar to those of members of the above groups. Only in captive horses (Equus caballus) has infant killing been reported. It has been estimated that 40,000 wild horses live in remote areas of the Great...
Plasma cortisol variations induced in the stallion by mating. Plasma cortisol variations have been determined by radioimmunoassay in 5 stallions during mating and in 2 teasers during oestrous female exposure. In all the animals, cortisol plasma levels consistently increase (71.1 ng/ml vs 44.0 and 63.0 ng/ml vs 35.1, in the stallions and in the teasers, respectively) 7-30 min after female exposure; 120 min after exposure, cortisol concentrations are again low.
Inheritance of an abnormal haemoglobin haplotype in horses and its possible influence on blood values. In a breeding experiment a stallion of the native Norwegian Trotter breed with an abnormal Hb haplotype (N) and with the Hb type BI/N, sired 6 offspring. The abnormal haplotype controls one α-chain only, having lysine at position 60 and phenylalanine at position 24. Three of the offspring received the N haplotype from the sire and the BII haplotype from the dam, whereas the other 3 offspring received BI from the sire. The BII/N horses have two Hb components after alkaline electrophoresis or isoelectric focusing with the ratio between the fast and the slow band (anodal, cathodal) being approxi...
[Topographico-anatomic data on the testicular artery, ductus deferens artery and cremaster artery in the stallion]. To study the vascularization of the testis of stallions we used 96 testes. We examined its topography and anatomy by roentgenography, stereoroentgenography, by the corosive method, and by means of gel and China ink injections. To make the roentgeno-arteriograms we used minimum emulsified in glycerine as contrast medium. The branching off of the Aa. testiculares from the Aorta abdominalis is variable in stallions. We observed also a peculiar age-dependent arrangement of the loops of the convolution. In the adult stallion, the shape of the convolution is either cylindrical or conical, spindle-sh...
Xylazine hydrochloride-induced hyperglycemia and hypoinsulinemia in thoroughbred horses. The effects of intravenous xylazine (1.1 mg/kg) were studied in six thoroughbred horses (five mares and a stallion). Plasma glucose concentration increased to 168% of control at 45 min and decreased to 112% of control at 180 min. Insulin had decreased to 31% of control at 15 min. Thereafter, insulin concentration increased, reaching its highest concentration at 150 min. The mechanism for these changes is not fully understood and further investigation is indicated.
Isolation of the contagious equine metritis organism from colts and fillies in the United Kingdom and Ireland. Between January 1978 and August 1982 the streptomycin resistant strain of the contagious equine metritis organism (CEMO) was isolated from 15 colts and two fillies in the United Kingdom and Ireland. A first season stallion was also suspected of having initiated an outbreak of contagious equine metritis (CEM) at the beginning of the 1982 breeding season. A detailed investigation of the breeding history of the dams and sires of each positive individual indicated that in a number of cases the CEMO was acquired either in utero or following transmission at the time of parturition. In several other ...
Experimental Brucella abortus infection in the horse: observations during the three months following inoculation. Five mares, one stallion and a colt foal were inoculated intraconjunctivally with Brucella abortus strain 544. No clinical signs of disease developed except mild pyrexia. Intermittent bacteraemia was detected in the mares but not in the stallion or foal. Antibodies to B abortus became detectable from the second week after inoculation. Titres in the serum agglutination and complement fixation tests declined substantially after six to eight weeks but reactions to the Coombs antiglobulin, 2-mercaptoethanol and immunodiffusion tests were maintained. No consistent changes in biochemical or haematol...
Estrogens in seminal plasma of human and animal species: identification and quantitative estimation by gas chromatography-mass spectrometry associated with stable isotope dilution. Estrone, 2-methoxyestrone and estradiol-17 beta have been definitely identified in seminal plasma of man, bull, boar and stallion by high resolution gas chromatography associated with selective monitoring of characteristic ions of suitable derivatives. Quantitative estimations were performed by isotope dilution with deuterated analogues and by monitoring molecular ions of trimethylsilyl ethers of labelled and unlabelled compounds. Concentrations of unconjugated and total estrogens are reported together with the statistical evaluation of accuracy and precision.
Effects of amikacin sulfate on the motility of stallion and bull spermatozoa at different temperatures and intervals of storage. Because microfloral content of stallion semen tends to be high, and strains may be resistant to commonly used antibiotics, amikacin was tested with stallion semen and compared with bull semen. Nine ejaculates to stallion semen were incubated at 37 C in egg yolk-tris extender for 0, 2, 4, 6, 8 and 10 h in the presence of amikacin concentrations of 0, 50, 100, 250, 500, 1,000 and 10,000 microgram/ml, with penicillin and penicillin-streptomycin as controls. Averaged over all incubations, spermatozoal motility was 44, 48, 49, 46, 45, 45 and 19%, for increasing concentrations of amikacin, compared ...
An electrophoretic investigation of mammalian spermatid-specific nuclear proteins. Using standardized methods for protein extraction and analysis, the testes of rams, bulls, goats, boars, stallions, rats, cats, hedgehogs, European mink and ferrets were examined for basic spermatid nucleoproteins by electrophoresis. The results suggest that differences exist in the total number of these proteins as well as in the number and amount of the cross-linked cystein-containing proteins. These differences appear to be more family-specific than species-specific.
[Two cases of tetany in the horse (author’s transl)]. Two cases of tetany in the horse are reported. The two patients were thoroughbreds. One was eight and the other thirteen years old. The mares were in heat and were brought to the service (stud) station to be mated. Both patients were nursing a foal. One was a four-week-old foal and the other was seven weeks old. The calcium level of the serum had dropped in the two patients, to 4.0 mg and 5.4 per ml. respectively. The magnesium level was 1.0 mg and 1.9 mg per 100 ml. respectively. The animals responded satisfactorily to intravenous infusion of calcium borogluconate and magnesium chloride. One ...
Effect of anabolic steroids on reproductive function of young stallions. Thirty-two stallions were used to determine the effect of anabolic steroids on reproductive function. Stallions were assigned to one of the four treatments: 1) .23 ml sesame oil/kg of body weight (BW; control, C); 2) 4.4 mg boldenone undecylenate/kg BW (4E); 3) 1.1 mg boldenone undecylenate/kg BW (1E) and 4) 1.1 mg nandrolone decanoate/kg BW (D). Injections were given at 3-wk intervals for 15 wk. Semen was collected every other day for 3 wk before the first injection and at the same frequency during d 85 through 105 (d 0 = day of first injection). Libido was assessed on the basis of reaction t...
