The Effect of Different Physical Exercise on Plasma Leptin,Cortisol, and Some Energetic Parameters Concentrations in Purebred Arabian Horses

Leptin is a hormone that coordinates food intake, energy expenditure, and metabolic rate; it is, however, unknown how exercise influences plasma leptin concentration in horses. The aim of the study was to evaluate the exercise-induced changes in plasma leptin concentration in purebred Arabian horses competing in races and endurance rides. A total number of 26 horses (12 purebred Arabian racehorses aged 3–5 years and 14 endurance horses aged 7–14 years) were studied during performing routine physical exercise. From each horse, blood samples were collected at rest and immediately after the exercise session. Concentrations of plasma leptin, cortisol, lactic acid, uric acid, triacylglycerols, glycerol and free fatty acids were determined. Exercise-induced increase in cortisol and free fatty acid values were higher in endurance horses than in racehorses. Neither endurance nor race exercises influenced the plasma leptin concentration. Further research is needed to elucidate the effects of different types of exercise on leptin synthesis and secretion in horses.     

Effect of Mineral Block Supplementation on In Vivo Digestibility and In Vitro Gas Production With Equine Fecal Bacteria

The effects of a mineral block for horses on in vivo digestibility and in vitro fermentability with equine fecal inoculum were evaluated. Fifty healthy horses from three groups (lactating mares n = 19, working horses n = 18, and maintenance horses n = 13) were randomly assigned to two treatment groups (with or without the mineral block; Ca 10.0%, P 12.0%, Zn 12.1 mg/kg, Cu 2,050 mg/kg, Mn 4,050 mg/kg, Se 30 mg/kg, and I 105 mg/kg). Dry matter digestibility was estimated with an internal marker. Samples of diet were incubated with equine fecal bacteria with varying amounts of mineral block (0, 1.1, 3.6, and 6.2 mg/g dry matter [DM]) to record gas production and to estimate in vitro DM digestibility. The results showed that mineral supplementation with the blocks increased in vivo DM digestibility (P < .01) in all groups, but there was an interaction (P < .01) with a greater response in the maintenance horses (55.5% vs. 78.0%) compared to lactating mares (62.8% vs. 79.6%) and working (70.3% vs. 75.1%). Block consumption was lowest in the lactating mares (12.8 g/d), intermediate in the working horses (44.6 g/d), and highest in the maintenance horses (74.2 g/d). The mineral supplementation did not affect the kinetics of gas production but tended (P = .10) to improve the in vitro DM digestibility (37.01% vs. 38.34%). Mineral block supplementation increased dry matter digestibility in horses. The unsupplemented control diet was deficient in several minerals, and block intake was not proportional to the mineral requirements.     

Effects of Sodium Caseinate and Varying Protein Sources on In Vitro Fermentation of Forages by Mixed Equine Cecal Microorganisms

To assess the impact of protein on fermentation by equine cecal microorganisms, cecal fluid from 4 cecally cannulated horses was used to inoculate fermentation bottles containing buffer, forage, and supplemental protein. In experiment 1, sodium caseinate (SC) provided 0, 0.5%, 1%, 2%, or 4% additional crude protein (CP) to bottles containing alfalfa or native warm-season prairie grass hay. Bottles were equipped with continuous gas pressure monitors and placed into a shaking incubator for 48 hours at 39°C. Cultures with alfalfa had greater (P < .0001) in vitro dry matter disappearance (IVDMD), neutral detergent fiber disappearance (NDFD), acid detergent fiber disappearance (ADFD), cumulative gas production, and total volatile fatty acid (VFA). Sodium caseinate increased gas production (P ≤ .05) and decreased pH (P < .003) in cultures with grass hay. Sodium caseinate at 1%, 2%, or 4% additional CP increased IVDMD, NDFD, and ADFD (P < .01), while 4% additional CP also increased total VFA (P < .01). For experiment 2, SC, fishmeal, soybean meal (SBM), whey, porcine blood plasma, and L-lysine hydrochloride were added to supply 2% additional CP to cultures with grass hay. All protein sources decreased pH and increased IVDMD, NDFD, and ADFD (P ≤ .01), with the largest effects elicited by SC, L-lysine, and whey (P ≤ .05). Total VFA (P ≤ .04) and gas (P ≤ .05) production increased with L-lysine, whey, SC, SBM, and fishmeal. While protein supplementation had minimal effects on cultures containing alfalfa, it altered fermentation of grass hay, more notably with more soluble protein sources.     

An In Vitro Investigation into the Effects of a Marine-Derived,Multimineral Supplement in Simulated Equine Stomach and Hindgut Environments

Management of the performance horse often incorporates meal feeding of highly digestible starches and reduced access to high-fiber forage. Such regimens are associated with equine gastric ulceration syndrome (EGUS) and can alter hindgut homeostasis. In-feed buffering of gastric contents and promotion of energy derivation from high-fiber forage in the hindgut are therefore desirable properties of a nutritional supplement. A marine-derived, multimineral supplement with known buffering properties containing calcium, magnesium, and short-chain fructo-oligosaccharides (scFOS) was tested under in vitro simulations of equine stomach and hindgut conditions. Six fiber:concentrate diets were incubated for 4 hours with or without the supplement at 37°C in pepsin HCl solution adjusted to pH 4.1 and 2.6. pH was measured at 1, 2, and 4 hours postincubation. Highest overall pH values were observed with the high cereal feeds; however, the supplement significantly increased (P < .001) the pH across all feeds by 0.17 and 0.19 for feeds incubated at pH 4.1 and 2.6, respectively. A gas production technique was used to measure the fermentation of four fiber:concentrate diets with and without additional supplement, using equine feces as the microbial inoculum. Addition of the supplement decreased (P < .05) the lag time and increased the initial fermentation rate, although as the incubation continued, this effect was reduced. These results demonstrate that the supplement had a significant buffering action for 4-6 hours under simulated in vitro stomach digestion conditions and also stimulated in vitro hindgut fermentation activities.     

Puncture of the Equine Embryonic Capsule and Its Repair In Vivo and In Vitro

Vitrification of embryos >300 µm in diameter requires puncture of the glycoprotein capsule, although the size of the hole compatible with embryo survival is unknown. Forty-five day-7 or -8 embryos were punctured using a 30-µm glass biopsy pipette mounted on a micromanipulator (n = 20) or manually with either an acupuncture needle (∼100-µm diameter -hole; n = 10) or a microneedle with a <1 µm tip to produce a ∼30-µm diameter hole (n = 15) before transferring to recipient mares; further 12 embryos were punctured with either the acupuncture needle or microneedle before being cultured in vitro for 48 hrs (n = 3 per puncture group) or transferred to recipient mares and recovered 48 hrs later (n = 3 per puncture group). No pregnancies resulted from the 10 embryos punctured with the acupuncture needle, whereas 15 of 20 (75%) and 10 of 15 (67%) punctured on the micromanipulator or manually with the microneedle resulted pregnancies. Neither acupunctured nor microneedle-punctured embryos repaired their capsules in vitro. The acupunctured embryos also failed to repair their capsule after 48 hrs in vivo and subsequent uterine flushing yielded numerous capsular vesicles. The microneedle-punctured embryos did repair their capsule in vivo. Puncture with the microneedle opens the way for development of a manual method to vitrify equine embryos.     

In Vitro Production of Equine Embryos and Cloning: Today's Status

Equine reproductive technologies, such as cloning and intracytoplasmic sperm injection (ICSI) have become routine laboratory practice in many parts of the world. In this review, we will discuss novel cloning approaches that have just recently become commercial, update the latest cloning results at Crestview Genetics in Argentina and at In Vitro Clonagem in Brazil, and discuss differences in techniques and approach within the American equine ICSI market from four different laboratories commercially producing equine ICSI.     

自由牧马对草甸草地群落结构及牧草品质的影响:以新疆昭苏夏马场为例研究

为探明自由牧马对草甸草地群落结构及牧草品质的影响,在新疆昭苏夏马场设置放牧试验,采用控制笼进行对照,分析了2013-2015年草地群落结构及牧草营养品质的动态变化。结果表明:(1)无芒雀麦(Bromus inermis)、羊茅(Festuca ovina)等一些马喜食的禾本科牧草的相对密度降低,狼毒(Euphorbia fischeriana)、龙胆(Gentiana scabra)等一些毒性植物和马不食植物的相对密度升高,但主要优势植物变化不大;(2)在3年夏场放牧中,草甸草地多样性指数(Simpson指数)维持在0.74～0.81;不同植物种类重要值变化趋势不同,白三叶(Trifolium repens)、草地早熟禾(Poa pratensis)和龙胆在群落中重要值增加,而细果苔草(Carex stenocarpa)和羊茅的重要值显著降低;(3)牧草中的中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)总体呈现上升趋势;粗蛋白(CP)含量随着放牧年限的增加从13.4%下降到11.3%,仍可达到马对粗蛋白含量(8%)的基本要求。由试验可知:目前的放牧强度(5匹马·ha-1)基本维持了草地的可持续性,但一定程度上降低了牧草的品质。     

Influence of Feeding Horses a High Fiber Diet With or Without Live Yeast Cultures Supplementation on Feed Intake,Nutrient Digestion,Blood Chemistry,Fecal Coliform Count,and In Vitro Fecal Fermentation

Sixteen Quarter Horse mares (body weight: 450–500 kg) were used in a complete randomized design to determine the effects of feeding horses a high fiber diet with or without yeast cultures addition on nutrient intake and digestion, blood chemistry, fecal coliform count, and in vitro fecal fermentation. The treatments were (1) a basal diet without yeast cultures addition (control treatment), (2) control diet plus Procreatin 7 at 15 g/mare/d (P7 treatment), (3) control diet plus Biocell F53 at 11 g/mare/d (F53 treatment), or (4) control diet plus Biosaf SC47 at 15 g/mare/d (SC47 treatment). The basal concentrate diet consisted of a mixture of 50% commercial concentrates and 50% wheat bran fed at 4 kg/mare and offered twice daily at 04:00 and 16:00 hours, while oat straw was offered ad libitum at 05:00 and 17:00 hours. The mares fed the F53 had higher (P < .05) oat straw and total nutrient intakes compared to the control diet. Addition of Biocell F53 and Biosaf SC47 yeast cultures increased (P < .05) all nutrients' digestibilities. Feeding the yeast cultures resulted in higher crude protein (P = .029), neutral detergent fiber (P = .042), and acid detergent fiber (P = .035) digestibilities compared to the control diet. The SC47 treatment had lower blood total protein (P = .014) than the control treatment. Higher (P < .05) asymptotic in vitro fecal gas production was obtained with F53 treatment compared to SC47 treatment without differences between F53, P7, and control treatments. Increased methane production was obtained (P < .05) with F53 and SC47 treatments compared to the control treatment. It can be concluded that daily addition of Biocell F53 yeast culture at 11 g/mare/d resulted in higher feed intake and nutrients digestibility without affecting the mare's health.     

Long-Term and Immediate Effects of Whole Body Vibration on Chronic Lameness in the Horse: A Pilot Study

The effects of whole body vibration (WBV) in horses with chronic lameness were evaluated in an experimental, single subject, repeated measure design. To assess the long-term effect of WBV, eight horses not previously exposed to WBV were subject to WBV, 30 minutes twice daily, five days a week, for 60 days in addition to their regular exercise routine. Lameness was assessed subjectively and objectively 30 days before the start, at the start and 30 and 60 days after the start of the treatment (WBV). The immediate effect of WBV was assessed in four horses accustomed to WBV, by comparing lameness before and within 30 minutes of a single 30-minute WBV session at four different time intervals. Change in lameness was sought using paired t tests on the kinematic data. A P-value of <.05 was considered statistically significant. Intraindividual change was sought using a subjective and objective scoring system. No statistically significant change in lameness was seen after 30 or 60 days of WBV, respectively, in the chronically lame horses not previously exposed to WBV. However, a trend toward improvement was observed after the first 30 days of WBV, but this improvement appeared to be lost during the second 30 days of WBV. Although a statistically significant worsening of front limb lameness was seen immediately after a single 30-minute WBV session in the chronically lame horses accustomed to WBV, this result was largely attributed to a very significant worsening of the front limb lameness in one horse within that group.     

Dyspnea Caused by an Obstructive Tracheal Leiomyoma in a Horse: A Rare Case

Tracheal leiomyoma is a rare neoplasm of the respiratory tract in animals. This primary benign tumor arises from smooth muscle cells of the trachea. We report a 13-year-old female horse with clinical signs of severe airways obstruction. It had dyspnea, exercise intolerance, chronic progressive respiratory noises, and cyanosis in mucosa membranes. Radiography revealed a foreign body obliterating the luminal trachea. Endoscopic biopsy showed a 3 × 3-cm ovoid mass attached to the dorsal aspect of the trachea. Hematoxylin and eosin and Masson's trichrome stains showed dense spindle cells forming irregular bundles disposed in short interlacing fascicles. Nuclei were elongated with blunt ends, eosinophilic cytoplasm with indistinguishable cell borders, and low mitotic activity. This study is considered the first reported case of an obstructive intratracheal leiomyoma in the horse.     

Multinodular Malignant Cutaneous Mast Cell Tumor in a Horse With Generalized Pruritus and Reactive Fibrosis: A Case Report

Mast cell tumor (MCT) has long been considered as an uncommon neoplasm in horses. Cytological and behavioral evidence of its malignancy is usually lacking, and only a few reports have described MCT displaying malignant behavior. An 18-year-old Friesian stallion presented with a one-year history of intermittent and progressive skin lesions on the left forelimb associated with intense, generalized pruritus and apathy temporarily responsive to glucocorticoids and antibiotics. The horse was alert and responsive with poor body condition and marked generalized pruritus. The left forelimb was markedly enlarged and surrounded by numerous firm 2- to 20-cm masses that were ulcerated and focally necrotic. A 7-cm round firm mass was observed on the left dorsal neck. Dermatological examination revealed generalized moth-eaten alopecia and scaling with erosions and ulcers secondary to pruritus. A direct skin smear from the affected leg showed severe eosinophilic inflammation and neutrophilic inflammation with pleomorphic bacteria. Histopathology of the skin and biopsies of the underlying tissues revealed an abundant population of atypical mast cells consistent with a malignant MCT. The horse was euthanized and necropsy revealed a marked fibrous reaction on longitudinal sections of the affected limb, and the tumor could be detected on only a few histological slides. Diagnosis of equine MCT can be challenging because of the massive accompanying fibrous reaction. Mast cell tumor should be suspected in the presence of eosinophilic infiltration of the affected tissue and in cases of generalized pruritus not attributable to other causes.     

Effects of Whole Body Vibration on the Horse: Actual Vibration,Muscle Activity,and Warm-up Effect

Whole body vibration (WBV) exercise has been introduced into human and recently also into equine training. Only a few studies about physical and physiological effects on horses are available. This study should clarify the actual physical vibration of a commercially available WBV plate itself and on the horse as well as the muscular activity in the limbs and back. Furthermore, the effects of WBV warm-up on clinical parameters and body surface temperatures were compared to standard warm-up exercises. Ten sound horses (vibration and muscle activity of six horses) were recorded while standing (control) and during 15 and 25 Hz (manufacturer information) vibration exercise. The vibration of plate, hoof, fetlock, withers, and sacrum was analyzed for frequency, peak-to-peak displacement, and peak acceleration. Activity of M. triceps, quadriceps, and longissimus dorsi was assessed using surface electromyography. Warm-up effects were compared between four different warm-up scenarios: standing (control), 10-minute vibration, 10-minute lunging (walk), and 12-minute lunging (walk and trot). Maximal body surface temperature of upper forelimb, thigh, and back was measured. Actual plate vibration frequency was 7 or 11 Hz with a maximum peak-to-peak displacement of 9 mm in longitudinal direction. WBV exercise induced no increase in electromyographic activity, clinical parameter, or body surface temperature. It was concluded that actual plate vibration was mainly longitudinal with a lower frequency than proposed and 10-minute exercise had no significant effect. Different vibration protocols and vibration acting in the vertical direction might enable more effective exercise in horses.     

艾维茵肉鸡和黄羽肉鸡脂肪和肌肉细胞生长发育规律研究

以艾维茵肉鸡和黄羽肉鸡各100羽为试验材料,在第3、6、9、12和16周龄时每品种随机抽宰3公3母,采取胸肌、腿肌和脂肪垫组织样品进行HE染色、石蜡包埋及切片后,在10×40倍显微镜下进行观察并测定脂肪细胞和肌纤维细胞直径。结果表明,脂肪细胞增殖与生长的分布图在9周龄前呈双峰分布,此后为单峰;艾维茵肉鸡胸肌纤维直径9周前为单峰,以后双峰或三峰分布,黄羽肉鸡胸肌纤维直径始终为双峰分布。腿肌纤维直径分布,两种鸡在3和6周龄时均为单峰,9周以后为多峰分布。说明主效基因可能在脂肪细胞和肌纤维增殖过程中发挥作用,并有活跃期和关闭期;肌纤维细胞直径增长遗传机理与脂肪细胞直径增长相同,但肌纤维直径增长的主效基因关闭和启动可能具有品种和部位的特异性。     

Isolation of Mare's Milk Oligosaccharide Fraction of Colostrum,Transitional, and Mature Phases Promotes In Vitro Oxidative Burst in Murine Macrophages

Present preliminary findings demonstrate in vitro stimulation of splenic lymphocytes of BALB/c mice after exposure to oligosaccharide fractions isolated from mare's milk during colostrum, transitional, and mature lactation periods, which shows immunostimulatory action of oligosaccharide content present in mares' milk. Oligosaccharide fractions caused more pronounced oxidative burst at a much lower concentration (0.1 μg/mL) compared with that shown by levamisole (standard immunostimulant) at a much higher concentration of 10 μg/mL. In this study, it was observed that oligosaccharides fraction of colostrum phase attaining high potency of immunostimulatory property.     

羧化胶乳凝集抑制试验快速鉴别牛肉和马肉的研究

以羧化聚苯乙烯胶乳作为载体,将牛血清和马血清分别共价交联到载体微球的表面,制成免疫微球.将此免疫微球同相应的抗血清配对,进行胶乳凝集抑制试验以鉴别牛肉和马肉.通过对265头份牛肉、242头份马肉、100头份猪肉、60头份羊肉、30头份狗肉、13头份骡肉和4头份驴肉鉴别,牛肉胶乳试剂和马肉胶乳试剂的敏感性均为100%,牛肉胶乳试剂的特异性为100%,马肉胶乳试剂同骡肉和驴肉呈完全交叉反应.实验具有良好的重复性和稳定性,试剂易于保存,本试验可在5min内报告结果,操作简便,适于基层动检部门应用.     

Cytotoxic Effects of Serum from Equine Grass Sickness Cases on Neuro-2a and PC12 Tet-Off Cell Lines: Implication for Using In Vitro Methods as Antemortem Diagnostic Tools

A wide variety of clinical and paraclinical methods have been used for diagnosis of equine grass sickness (EGS), but none of them could absolutely confirm the diagnosis, and postmortem pathologic examination is still considered the final step in precise diagnosis of EGS. Use of in vitro cell toxicity caused by EGS serum on neuronal cell lines was investigated. Three well-known cytotoxic methods were used to investigate the cytotoxicity of EGS serum on neuro-2a and genetically engineered PC12 Tet-Off P53 cells. The results of alamar blue reduction as an index for mitochondrial activities and intracellular adenosine triphosphate content assays, but not neutral red uptake, indicate that the EGS serum may affect the mitochondrial function and cellular metabolism at up to 60% of the cases. The results of present study might be used for diagnosis of EGS cases. Further studies with high sample size may lead us to uncover the pathogenesis of EGS and to increase the sensitivity and applicability of in vitro techniques as diagnostic tools.     

Fatty Acid Composition of Porcine Muscle and Adipose Tissue Lipids as Affected by Anatomical Location and Cod Liver Oil Supplementation of the Diet

In pigs fed a standard pig mash the contents of polyunsaturated fatty acids (PUFAs) of both the n-6 and n-3 series were significantly higher in the dark red mm adductores compared to the light coloured m longissimus lumborum. Perirenal fat had a higher concentration of saturated fatty acids (14:0,16:0, 18:0) than backfat, and a lower concentration of monounsaturated fatty acids, such as 16:ln-7 and 18:ln-9. Daily supplementation of 50 ml cod liver oil, rich in n-3 PUFAs, during the fourth and third week before slaughter led to a 1.4 to 1.7 times increase in the contents of n-3 PUFAs in muscles and fat depots. There was no difference between the incorporation of n-3 PUFAs in dark and light muscles. Perirenal fat contained more 20:5n-3 (EPA) and 22:6n-3 (DHA), but less 20:ln-9 (eicosenoic acid) than the backfat, after cod liver oil supplementation rich in these 3 fatty acids. Supplementation of cod liver oil reduced the n-6/n-3 fatty acid ratio in all anatomical locations examined.     

Vitiligo in a Quarter Horse Filly: Clinicopathologic, Ultrastructural, and Nutritional Study

Vitiligo is an autoimmune disorder characterized clinically by depigmentation of the skin—both epidermis and hairs—caused by destruction of melanocytes. Vitiliginous skin shows a T-lymphocyte inflammatory infiltrate, proliferation of Langerhans cells, epidermal vacuoles, and degenerative changes in the cutaneous nerve fibrils. Increased autoantibodies against melanin, tyrosinase, and various tissues are frequently present in vitiligo patients. Vitiligo is often associated with systemic abnormalities or nutritional deficiencies. A 2-year-old Quarter Horse filly developed facial vitiligo with depigmented areas that was strikingly similar to human vitiligo. Several innocuous small biopsies provided cutaneous specimens that were processed for light and electron microscopic studies. Many of the clinical and microscopic changes observed in human vitiligo were present in this equine patient. Marginal anemia was detected. Strengthening of the filly's nutritional and feeding conditions led to rapid and complete repigmentation. Equine practitioners as well as horse owners should be aware that vitiligo may not be simply a cosmetic problem; thus, a complete evaluation of horses affected by this condition should be performed.     

Exercising Blood Gas Analysis, Dynamic Upper Respiratory Tract Obstruction, and Postexercising Bronchoalveolar Lavage Cytology—A Comparative Study in Poor Performing Horses

Respiratory abnormalities are common causes of decreased performance in horses presumably because of impaired pulmonary gas exchange. The objectives of the present study were to describe respiratory abnormalities in poorly performing horses and to investigate the relationships between dynamic upper respiratory tract (URT) videoendoscopy, postexercising bronchoalveolar lavage (BAL) cytology, and exercising arterial blood gas analysis. Medical records of 93 horses with exercise intolerance, which presented for treadmill evaluation, were reviewed. Relationships between horse demographics, treadmill endoscopic findings, exercising blood gas values, and BAL cytology results were examined. A total of 25 (27%) horses had a URT obstruction and 91 (98%) horses had abnormal BAL cytology; 73 (78%) had evidence of inflammatory airway disease (IAD) and 83 (89%) had exercise-induced pulmonary hemorrhage (EIPH). In all, 39 (42%) horses had abnormal blood gas values. Dynamic URT obstruction was significantly associated with exercising hypoxemia (P = .036). There were no significant relationships between gas exchange and IAD or between EIPH. Out of 24 (26%) horses with combined URT obstruction and abnormal BAL, horses with URT obstruction and EIPH were more likely to be hypoxic during exercise (P = .037). It was concluded that horses with dynamic URT abnormalities are likely to have exercising hypoxemia. Although IAD and EIPH were commonly indentified in poor performers, they were not significantly associated with abnormal exercising blood gas analysis.