Effect of Season on Travel Patterns and Hoof Growth of Domestic Horses

Four Morgan mares and five Morgan geldings ranging in age from 5- to 12-years-old were fitted with Global Positioning System units to determine if season has an influence on travel pattern. Body and hoof growth measurements were obtained so that the influence of season on body condition and hoof growth could be determined. Waist and heart circumference, cresty neck score, and body condition score were determined in each season. The ambient temperature and precipitation was recorded for each season. Waist circumference was the greatest (P < .05) in the spring and summer and the least in the fall and winter. Hoof growth was the greatest (P < .05) in the fall and the least in the winter. The front and rear hooves grew at similar rates in all horses. Hoof growth in geldings and mares were also similar. The average distances traveled were similar across seasons; however, the horse did numerically travel more in the spring and summer compared with the fall and winter. The range of the travel pattern was influenced by season with the horses traveling significantly less in the winter, although the average travel distances were similar. In conclusion, season in temperate zones will influence body condition, hoof growth, and pattern of travel, but the total distance traveled will be similar. Further research needs to be conducted to determine the influence of season on hoof growth and travel patterns.     

Clinical Outcome of 14 Obese,Laminitic Horses Managed with the Same Rehabilitation Protocol

A specific method of rehabilitation was used to manage obese horses with laminitis, and clinical outcome was evaluated after 5 to 20 months. Clinical data from 14 similar laminitis cases were statistically analyzed to evaluate response to rehabilitation. Data were analyzed using repeated measures or logistic regression methodologies. Each horse presented as obese and laminitic with no history of a systemic inflammatory disease. The rehabilitation method emphasized a mineral-balanced, low nonstructural carbohydrate diet; daily exercise; hoof trimming that minimized hoof wall loading; and sole protection in the form of rubber hoof boots and/or hoof casts. Distal phalanx alignment within the hoof capsule was significantly improved, and hoof wall thickness was significantly decreased (P < .0001) following treatment. Solar depth was significantly increased (P < .0015). Reduction of palmar angle measurements was detected in acutely and chronically affected horses. This treatment effect was statistically greater for horses with chronic laminitis than for horses with acute laminitis (P interaction < .0001). Horses were 5.5 times more likely to be sound post-treatment than before treatment. Daily exercise, dietary modification, and removal of ground reaction force from the hoof wall were foci of the rehabilitation program. Hoof care and husbandry as applied to these horses may be an effective method of rehabilitation of horses from obesity-associated laminitis.     

Laminitis: Recognition of At-Risk Individuals,and Methods of Prevention

Even with the many advances made in the understanding of the pathophysiology, new treatments and preventative measures, laminitis continues to plague the equine population. Identification of risk factor and at-risk individuals remains the best approach with this disease.     

Rehabilitating the Chronically Laminitic Foot

Trimming and shoeing the equine patients suffering with chronic laminitis entails a well organized approach, improves quality of life and generally results in a better outcome. The chronic laminitic hoof presents clinically in a variety of ways and thus treatment needs to be tailored to the individual horse.     

Laminitis in Horses: Through the Lens of Systems Theory

Systems theory is a way of describing complex and dynamic relationships. We applied systems theory to the structure and function of the equine foot in an effort to better understand laminitis and, in so doing, reconcile the various theories of its etiopathogenesis and find more universally effective preventive and therapeutic strategies. The foot is described as an open system, and its inherent vulnerabilities are explored. Cascade failure is discussed as a potentially unifying theory of laminitis. The fundamental failure in laminitis is failure of the lamellar dermal−epidermal bond, but that endpoint can be reached via vascular, enzymatic, inflammatory, or mechanical mechanisms, or any combination thereof. Inflammation is discussed as a common denominator, making anti-inflammatory therapy of greater importance than just pain management. Multimodal anti-inflammatory therapy is discussed, including selective COX-2 inhibitors, heparin, nutraceuticals, and inhibitors of matrix metalloproteinases (MMPs). Multimodal analgesic therapy also is important and may include nonsteroidal anti-inflammatory drugs (NSAIDs), opiates, epidural analgesics, physical therapy, relief of weight bearing, diligent nursing care, deep digital flexor tenotomy, and case-appropriate trimming and shoeing. Preventing laminitis still comes down to risk management: knowing the risk factors applicable to an individual horse and adjusting the management accordingly. Examples include weight management and control of carbohydrate intake in overweight horses and ponies, the use of pergolide in patients with pituitary pars intermedia dysfunction (PPID), and distal limb cryotherapy in high-risk patients. It is anticipated that application of molecular biologic techniques will further advance treatment and prevention of laminitis.     

放牧家畜模拟践踏器研究

放牧家畜践踏在草地退化和健康维护中起主导作用而具有重要的研究意义。结合放牧家畜放牧行为和踏压作用力分析,采用气泵与践踏器直接连接的设计,研制了"手持式气动放牧家畜模拟践踏器"。"手持式气动放牧家畜模拟践踏器"是一种精确模拟放牧家畜的践踏作业的手提便携式专业工具。通过压缩气体进入汽缸,推动活塞上下运动,模拟放牧家畜的践踏作用,模具平台前装有活动关节可同时模拟放牧家畜践踏的"摩擦削切作用",由于汽缸工作压力大小可调节,践踏次数可计数,从而实现对牛、马、羊等放牧家畜的践踏可调节、可计量的目的。该机设计结构紧凑、体积小、重量轻、机动性强、手提便携、性价比高,特别适用于小尺度研究各种放牧家畜践踏对任意类型草地的作用。     

奶牛蹄病发生规律及综合防控措施

为了降低奶牛蹄病的发病率,促进奶牛业健康发展,笔者对某大型奶牛场开展了奶牛蹄病发生规律的调查及综合防控措施研究。结果表明,该奶牛场蹄病年平均发病率达24.2%,其中:不同季节奶牛蹄病的发病率以第三季度最高,达39.8%;不同年龄奶牛蹄病的发病率以5～7岁最高,达39.1%;不同胎次奶牛蹄病的发病率以第4胎次最高,达45.4%;泌乳奶牛蹄病的发病率随泌乳量的增加而升高。自采取综合防控措施以来,该规模化奶牛场蹄病发病率逐年下降,由2006年的34.7%下降至2010年的11.9%,防控效果显著。     

Long Toes in the Hind Feet and Pain in the Gluteal Region: An Observational Study of 77 Horses

This study deals with the relationship between long toes in the hind feet and pain in the gluteal region in horses, and the remedial value of trimming/shoeing that moves the breakover point back at the toe. Seventy seven client-owned horses were studied, 67 shod riding horses retrospectively and 10 barefoot broodmares prospectively. The 10 mares were evaluated twice, and 24 of the 67 riding horses were re-evaluated at the next shoeing, for a total of 111 observations. Each horse underwent gluteal palpation and lateral radiographs of both hind feet. Toe length was quantified as breakover distance (BD), the horizontal distance between the tip of the third phalanx and the dorsalmost point at which the wall/shoe was in contact with the ground. The BD was then shortened with trimming +/− shoeing to a length of ≤15mm (shod horses) or ≤20 mm (barefoot horses). The 24 riding horses were re-evaluated 4-6 weeks later and the 10 broodmares 1 week after trimming.     

蹄变形奶牛血液流变学的研究

为了更深入探讨奶牛变形蹄的发病机理及对奶牛变形蹄的预防和治疗提供更科学的理论依据。选择长沙地区20头中国荷斯坦牛，系统检测了变形蹄和正常蹄奶牛在夏季（6月份）和冬季（12月份）血液流变学主要指标。夏季时，1S-1、3S-1、5S-1、10S-1、30S-1、60S-1切变率下，变形蹄奶牛全血粘度高于正常蹄奶牛，有显著差异（P〈0．05）。变形蹄奶牛低切全血还原粘度极显著高于正常蹄奶牛（P〈0．01）。变形蹄奶牛红细胞压积高于正常蹄奶牛，差异显著（P〈0．05）。冬季时，5S^-1、10S^-1、30S^-1、200S^-1切变率下，变形蹄奶牛全血粘度高于正常蹄奶牛（P〈0．05）。变形蹄奶牛血浆粘度高于正常蹄奶牛，有显著差异（P〈0．05）。变形蹄奶牛红细胞沉降率较快，也有显著差异（P〈0．05）。变形蹄奶牛与全血粘度增高和红细胞聚集性增强具有相关性。     

A Cross-Sectional Survey of Forelimb Hoof Conformation and the Prevalence of Flat Feet in a Cohort of Thoroughbred Racehorses in New Zealand

Racehorses in New Zealand predominantly train counter clockwise. This training pattern has been associated with between forelimb differences in bone mineral density profile and asymmetrical limb loading after training. At present, there is limited data on the hoof conformation of these racehorses. Distal forelimb and digital hoof conformation data were collected from 75 Thoroughbred racehorses (2–5 years old) from two training yards. Digital conformation was subjectively graded, and multiple hoof measurements were made with a modified tire gauge (sole and sulci depth) and from digital photographs. All the horses were shod by two registered master farriers within a median of 15 (interquartile range [IQR], 1–25) days before measurement. There were few distal limb conformation abnormalities scored. Most (62/75) horses presented with some deviation from normal hoof parameters, with 2 (IQR, 1–3) abnormalities reported per horse. The most common hoof abnormality was uneven sulci, which was identified in 43 horses and 59 affected hooves, followed by higher medial hoof wall height in 38 horses and 53 affected hooves. Many of the linear and hoof angle measurements and their ratios were within the bounds reported within the literature and indicative of a balanced foot. The length and width measurements increased with horse age. The dorsal hoof wall (DHW) length:heel length ratios were consistently less than 3:1, and the absolute difference between toe and heel angle was generally greater than 5°. Between limb hoof variation was identified for a number of the morphologic measurements including frog length and sole length and the ratio of sole width:sole length. Flat feet (lack of concave solar surface) were identified in 21/75 (28%) horses and in 28/150 (19%) forelimb hoofs. More horses had a flat left foot (10/75) than right foot (4/75), but seven horses had both feet classified as being flat. Flat feet had 2.4 (1.1–5.6, P = .036) greater odds of presenting with uneven sulci. These data indicate that uneven sulci depth and flatter hooves with may be a typical presentation of Thoroughbred feet. Asymmetry in measurements between limb may reflect the greater loading of the left forelimb when race training counter clockwise.     

Clinical Application of Current Research Findings Toward the Prevention and Treatment of Acute Laminitis in Horses With Systemic Inflammatory Diseases: An Internist’s Perspective

Laminitis is most commonly caused by metabolic disorders or systemic inflammatory diseases. There are numerous recent publications that have reported on pathophysiology of laminitis associated with systemic inflammation. These studies include both in-vitro and in-vivo models investigating inflammatory profiles, vascular reactivity or oxidative stress at different stages of development or clinical laminitis and some studies have proposed therapeutic interventions. Although the amount of information in these studies is great and quality of the research is often outstanding, it has not always been clear how these findings might be applied to clinical practice. This article is intended to report one internist's perspective on recent research findings on the pathophysiology and prevention of laminitis in horses with systemic inflammatory diseases and how these findings might be applied to clinical practice.     

Some Observations on the Materials Used in the Management of Foot Pain

There are a wide range of polymers available for supporting the equine hoof. A review of the material characteristics of materials used to support the laminitic hoof in the form of sole support, as well as an examination of the thermal effect of exothermal adhesives at the level of sensitive tissue in the foot and the long term effect of a fabric cuffed shoe on the amount of distortion to the dorsal hoofwall at the toe.     

Management of the Dorsal Hoof Wall and Its Potential Effects on the Laminitic Hoof

Appropriate management of the equine hoof during chronic laminitis varies by protocol and practitioner. Sequential removal of the dorsal hoof wall was examined in-vivo on a laminitic horse at the walk, revealing an increase in solar force under the margin of the distal phalanx as measured through the use of an in-shoe force measuring system.     

蛋氨酸锌对肢蹄病绒山羊抗氧化能力和肢蹄病相关指标及肢蹄健康的影响

选择20只舍饲肢体病辽宁绒山羊母羊,随机分成5组,其中1组为对照组,2～5组为试验组,各组每只羊依次补饲蛋氨酸锌0、342、515、686、857 mg/d(折算为锌分别是0、60、80、120、150 mg/d)。饲养60 d后,采集静脉血样测定营养代谢指标、抗氧化指标和骨关节损伤生物学标志物,试验结束时连续3 d观察试验羊肢蹄状况。结果表明:随着蛋氨酸锌补饲量的增加,血清INS和PG含量均呈现降低趋势,其中4、5组的INS和PG显著(P<0.05)低于对照组,血糖呈增加趋势,其中4、5组显著(P<0.05)高于1组。血清UA含量呈降总体低趋势;血清UN水平呈总体增加趋势,试验5组显著(P<0.05)高于对照组。血清GSH-PX、SOD、CAT、GSSG活性呈增加趋势,其中4、5组GSH-PX、CAT、GSSG显著(P<0.05)高于对照组,4、5组的SOD和CAT活性极显著(P<0.01)高于对照组;血清MDA呈降低趋势。血清COMP、CTX-Ⅱ和PⅡANP含量都呈降低趋势,其中5组COMP、CTX-Ⅱ的含量显著(P<0.05)低于对照组。经观察发现补饲蛋氨酸锌后肢蹄病羊的关节肿大、关节僵直、跛行、跪地膝行等症状得到明显改善。结论:在舍饲肢蹄病羊日粮中添加120～150 mg/d蛋氨酸锌显著提高了机体抗氧化能力,保护了关节软骨免受损害,对促进肢蹄病羊恢复具有明显作用。