Topic:Arteries
Arteries in horses are blood vessels responsible for carrying oxygenated blood away from the heart to various tissues and organs throughout the body. These vessels are integral to the circulatory system, facilitating the delivery of essential nutrients and oxygen to maintain cellular function and overall health. The structure of equine arteries includes a thick muscular wall that accommodates the high pressure of blood flow, allowing for efficient transport. Research on equine arteries often focuses on their anatomical characteristics, physiological functions, and potential disorders that may affect them, such as atherosclerosis or aneurysms. This page compiles peer-reviewed research studies and scholarly articles that examine the anatomy, physiology, and pathophysiology of arteries in horses.
Epidemiology of Strongylus vulgaris infection of the horse in Morocco. Between August 1978 and July 1979 the anterior mesenteric artery and its branches were collected regularly from adult horses and examined for Strongylus vulgaris larvae. The incidence of infection varied from 55 to 100% (annual mean 80%). The mean monthly number of larvae ranged form 3 to 22 with an annual overall mean of 13. The arterial infection was at its minimum in December to January, rose gradually to attain the peak in June and declined thereafter. These observations indicated that S. vulgaris is an annual species in Morocco, infection occurring during the rainy season (November-April)...
Surgical technique and considerations for implantation of electromagnetic blood flow transducer and occluder onto the coronary arteries. A technique was developed for the implantation of an electromagnetic flow probe and vascular occluder onto the right and left coronary arteries in the calf and pony. Surgical manipulation was well tolerated in the animals. The subcutaneous housing on the peripheral ends of these devices of the lateral thoracic wall served as a maintenance-free technique for chronic exteriorization of these devices. Implantation onto the coronary arteries required a surgical technique which accomplished the prerequisites for proper flow probe function. A reactive hyperemic response was elicited in each animal b...
Vascular supply of the equine stifle joint. The vascular supply of the equine stifle joint was investigated, using latex vascular injections of pelvic limbs from 3 adult horses and 6 ponies. Vessels were grossly dissected to the small arteriole level. The primary source of blood supply was the femoral artery and its branches which entered the joint on the caudal and medial surfaces. The superficial vasculature arose from the caudal branch of the deep circumflex iliac artery cranially and laterally, and from the saphenous and descending genicular arteries medially. The deep vasculature arose from the popliteal artery and its branches on ...
Influence of head height on arterial blood pressure in standing horses. Eighteen horses were used to investigate the influence of head position on arterial blood pressure, measured indirectly at the coccygeal artery. Head height significantly altered systolic pressure, diastolic pressure, pulse pressure, and mean arterial pressure, such that head-lowering decreased and head-raising increased all variables.
Assessment of wall shear stress in arteries, applied to the coronary circulation. Time dependent wall shear rates cannot be directly or accurately measured in arteries using presently available techniques. Here a simple method is presented for calculating them from a single measured velocity waveform (either centreline or cross-sectionally averaged velocity). The method involves only Fourier analysis and the application of given formulae, and it is expected to be approximately valid in any segment of artery which has no branches or sharp curves for a distance of several diameters. It is shown, however, that a frequency response of 30 Hz is required in the velocity measuring...
Lactic acidosis and arterial hypoxemia during sublethal endotoxemia in conscious ponies. Effects of a sublethal IV dose (10 micrograms/kg of body weight) of Escherichia coli endotoxin were studied in 7 conscious ponies. Arterial blood gases and plasma lactic acid were determined periodically throughout the 180 minutes of the study. Arterial hypoxemia occurred within 5 minutes despite intense hyperventilation. Colic and diarrhea occurred in all ponies within 30 minutes after endotoxin administration. Metabolic acidosis developed within 30 minutes and persisted throughout the study, indicating widespread reduced tissue perfusion.
Electromagnetic measurements of metacarpal blood flow in nonanesthetized horses. Blood flow (milliliter/minute) was measured in the medial palmar artery of 12 horses, using electromagnetic flow equipment. Extraluminal flow probes were surgically placed around the artery and base-line blood flows were recorded during surgical manipulation. After horses had recovered from anesthesia, blood flows were recorded each day for 11 days. According to mean average blood flows, horses were allotted to two groups: group 1--those with predominately normal flow characteristics, and group 2--those horses with predominately abnormal flow features. Average daily mean blood flows in the med...
Vascular responses in equine thoracic limb during and after pneumatic tourniquet application. Vascular responses occurring with pneumatic tourniquet application were evaluated in the equine thoracic limb. Recordings of pressure (arterial and venous) and flow (arterial) distal to the tourniquet were made for 60 minutes. Reactive hyperemia was observed; however the increased flow was neither of a sufficient duration nor of a great enough volume for total repayment of flow loss.
Occlusion of internal carotid artery in the horse by means of a balloon-tipped catheter: evaluation of a method designed to prevent epistaxis caused by guttural pouch mycosis. A procedure developed to occlude the internal carotid artery of horses with guttural pouch mycosis was modified was modified and evaluated in nine clinically normal horses. The left internal carotid artery was ligated at its origin and occluded distally with an intraluminal balloon catheter. In four horses, the balloon-tipped catheters were left in place until these horses were euthanatized at 4 to 244 days after surgery. In the remaining horses, the catheters were removed after 10 to 14 days by a cutdown procedure, and these horses were euthanatized 1 to 60 days after catheter removal. In bot...
Occlusion of internal carotid artery in the horse by means of a balloon-tipped catheter: clinical use of a method to prevent epistaxis caused by guttural pouch mycosis. An intravascular procedure was used to occlude the internal carotid artery of two horses with epistaxis caused by guttural pouch mycosis. In each horse, the affected internal carotid artery was ligated close to its origin. A balloon-tipped catheter was introduced into the artery distal to the ligature, and its tip was advanced beyond the site of infection. The balloon was then inflated so that the infected segment of artery was isolated from the cerebral vascular system. The catheters were removed at 14 and 51 days, and both horses were returned to training and racing. Neither horse had furthe...
Equine verminous arteritis. An arteriographic evaluation of the larvicidal activity of albendazole. Albendazole was an effective larvicidal anthelmintic against the fourth stage Strongylus vulgaris larvae as late as one month post-infection. The drug was administered at a dose rate of 25 mg/kg three times daily for 5 days. Diarrhoea occurred in 3 of 4 foals treated and of these one died during belated intravenous therapy for dehydration. Arteriography allowed for an in vivo assessment of the development and regression of lesions in infected-treated foals compared to the continued development of lesions in infected-untreated foals. The arteriographic findings were confirmed at necropsy.
Coronary artery pressure development and wave transmission characteristics in the horse. Measurements of the pressure waveform development and the wave transmission characteristics in the left extramural coronary arteries of the horse have been carried out. Near the ostium the left coronary pressure waveforms are seen to be virtually identical to the corresponding aortic root waveforms; however, the present of low frequency, relatively large amplitude pressure oscillations (on the order of 5 to 10 Hz) gradually become the dominant diastolic feature as one proceeds distally from the left ostium, and these eventually completely mask the incisura. In a limited number of experiments, ...
Ischaemic necrosis of the navicular bone and its treatment. In a survey of 95 control horses and 16 horses with navicular disease, the incidence of erosions and discoloration of the flexor cartilage of the navicular bone was no different between the control horses and those with navicular disease. All cases of navicular disease showed thrombosis of the distal navicular nutrient arteries and this could be related to a change to a rounded or flask shape of the distal nutrient foramen of the navicular bone. Erosions and discoloration of the navicular bone are therefore of no significance in navicular disease. Previously described lines of treatment are of...
Corticosteroid-potentiated vascular responses of the equine digit: a possible pharmacologic basis for laminitis. Spirally cut digital arteries and veins were mounted isotonically in organ baths containing oxygenated Krebs' Q-Henseleit solution. Twelve arterial and 12 venous preparations all contracted dose dependently when epinephrine, norepinephrine, serotonin, or histamine were added to the bathing fluid. Addition of hydrocortisone or betamethasone alone did not cause contractions in any of the tissues tested. However, when hydrocortisone or betamethasone was added to vessel strips that were partially contracted (40% to 60% maximal) by epinephrine, norepinephrine, or serotonin, each vessel strip invari...
Haemodynamics in the horse: 2. Intracardiac, pulmonary arterial and aortic pressures. The paper reports the changing pressure values during the cardiac cycle recorded from various chambers of the heart and great vessels using 2 catheter-mounted transducers, 9 cm apart. Pulse pressures are calculated. Transvalval pressure differences are determined taking account of the effect of hydrostatic pressure between the 2 sensors. The effects of some valvular lesions and arrhythmias and of changes in intrathoracic pressure are also described.