The Effects of Selenium Source on Measures of Selenium Status of Mares and Selenium Status and Immune Function of Their Foals

The effect of organic and inorganic sources of selenium (Se) on measures of Se status of mares and their foals, Se concentrations of colostrum and milk, and indices of immune function of foals was studied. Twenty late-gestation Standardbred mares were randomly assigned to one of two groups. All mares received an identical balanced ration, except for the source of supplementary Se: one group received organic Se (Se yeast) and the other group received inorganic Se (sodium selenite), fed to deliver 0.3 mg/kg supplementary Se based on total ration dry matter. Mares received the experimental diet from 2 months before estimated due date until 1 month after foaling. Source of Se did not affect Se concentrations in maternal plasma, red blood cells, colostrum, or milk. At 1 month of age, foals from mares fed organic Se had higher red blood cell Se concentration than foals from mares fed inorganic Se (P < .05). Measures of immunity included serum immunoglobulin G concentration, lymphocyte proliferation in response to concanavalin A, and relative cytokine gene expression of stimulated lymphocytes (interferon gamma [IFNγ], interleukin [IL]-2, IL-5, IL-10, tumor necrosis factor alpha [TNFα]) and neutrophils (IL-1, IL-6, IL-8, IL-12, TNFα). Relative gene expression of IL-2, TNFα, and IFNγ by foal lymphocytes was associated with the source of Se supplementation provided to the mares. We conclude that the source of dietary Se provided to mares may influence the immune function of foals at 1 month of age through changes in relative gene expression of certain lymphocyte cytokines.     

硒与水生动物免疫功能的关系

硒是水生动物的必需微量元素之一。它能影响水生动物对疾病的抵抗力,增强其细胞免疫和体液免疫功能,从而维持动物机体的健康状态,提高动物的生产性能。本文重点阐述了硒对水生动物疾病抵抗力、细胞免疫和体液免疫功能的影响以及硒影响水生动物免疫功能的可能机制。     

Uterine Inertia due to Severe Selenium Deficiency in a Parturient Mare

A 12-year-old, multiparous, parturient show jumper embryo-recipient mare presented at a veterinary hospital, seven days past her due date and with a dilated cervix, for evaluation of mild colic. Gastrointestinal or metabolic abnormalities and fetal maldispositions were excluded as causes of dystocia, and a diagnosis of uterine inertia was made. There was no uterine response to oxytocin treatment. A live filly was delivered via C-section, and severe selenium deficiency was eventually confirmed in the mare, her offspring, and in the herd of origin. The filly was born with severe white muscle disease and required intensive treatment. This report suggests that selenium deficiency is an underlying cause of equine uterine inertia in the absence of other causes of dystocia.     

Status of Lipid Peroxidation, Antioxidants, and Oxidation Products of Nitric Oxide in Equine Babesiosis: Status of Antioxidant and Oxidant in Equine Babesiosis

Equine babesiosis is a tick-borne protozoal disease of horses caused by Theileria equi and Babesia caballi. The disease is endemic in most tropical and subtropical areas. The aim of this paper is to assess the antioxidant status, lipid peroxidation, and oxidation products of nitric oxide (NO) in horses and mules naturally infected with T. equi and B. caballi. East and Southeast Anatolian horses and mules living in rural region of the Eastern border of Turkey were used as the material for this study. These animals are used as pack animal (3–7 years of age). Infected animals were in acute or subacute infection period. In the current study, malondialdehyde (MDA), oxidation products of NO (nitrate and nitrite), serum glutathione (GSH), vitamin E, and retinol levels were analyzed in 58 equids (horse and mule) infected with T. equi and B. caballi as well as in 44 healthy equids. Compared with controls, the level of MDA and nitrate increased significantly (P < .01, P < .05, respectively), whereas GSH concentration and levels of vitamin E decreased significantly (P < .01). There was no significant change in the level of nitrite and retinol between two groups. The results of the current study suggest that in equids infected with T. equi and B. caballi, this alteration in the lipid peroxidation, oxidants, and antioxidants may be related to the host's defenses against parasitic infection and may play a central role in the pathologic conditions associated with babesiosis.     

Lack of Detectable Equine Herpesviruses 1 and 2 in Paraffin-Embedded Specimens of Equine Sarcoidosis

Background: Equine sarcoidosis is a rare, multisystemic, noncaseating, granulomatous and lymphoplasmacytic disease of unknown etiology. A recent report described a horse with granulomatous skin disease displaying histologic, electron microscopic, and polymerase chain reaction (PCR) findings consistent with equine herpesvirus 2 (EHV-2).
Objective: To investigate the presence of EHV-2 and equine herpesvirus 1 (EHV-1) in 8 horses with sarcoidosis.
Animals: Eight horses with sarcoidosis, reported previously.
Methods: Retrospective study. PCR assays of the tissues were performed to detect DNA associated with EHV-1 and EHV-2. For both herpesviruses the target was their respective glycoprotein B gene. Positive controls consisted of DNA from viral cultures of culturettes from naturally occurring respiratory infections of EHV-1 and EHV-2.
Results: The PCR analyses for both equine herpesviruses' DNA were negative in all 8 horses.
Conclusion: The failure to detect DNA from EHV-1 and EHV-2 in paraffin-embedded skin of these 8 horses does not discount EHV-1 or EHV-2 as causing some cases of ES, but lends support to the presumably multifactorial etiologic nature of the disease.     

阻抗法评价静松灵对马心功能的影响

本实验首次以无损伤性电阻抗技术,对10匹实验马应用静松灵后的心血管状态进行了监测。结果表明,肌注静松灵后,实验马心率、心输出量、单位体重心输出量、心室最大射血速率显著下降,左室射血时间、总机械收缩时间显著延长,每搏输出量没有显著变化.有的马还出现心律不齐,房宣传导阻滞和心音分裂。     

不同硒水平对幼鲤生产性能和免疫功能的影响

选择体重约10.4 g的健康幼鲤960尾,随机分为8组,每组3个重复,每个重复40尾,分别饲喂添加硒(亚硒酸钠,分析纯)0、0.1、0.2、0.3、0.4、0.5、0.6、0.7 mg/kg的8种不同饵料,试验期90 d。结果表明:随着饵料中硒添加水平的增加,幼鲤的增重和成活率提高,饵料系数降低,添加硒0.4mg/kg时,幼鲤生产性能最佳(P<0.05);添加0.3～0.5 mg/kg硒,可显著提高幼鲤头肾和脾脏重及其体指数,增加血液红细胞数量,降低白细胞数量,提高血清IgM水平和攻毒后成活率、血清溶菌酶活力及血清凝集抗体效价(P<0.05),从而增强幼鲤免疫功能和对疾病的抵抗力。幼鲤体增重、饵料系数、头肾重量、脾脏重量、血清溶菌酶活力和IgM抗体水平与饵料硒添加量呈显著的二次曲线相关。根据上述指标确定的最适硒水平为0.396～0.529 mg/kg。     

Equine Granulocytic Anaplasmosis

Equine granulocytic anaplasmosis (EGA) is a seasonal rickettsial disease of horses transmitted by Ixodes spp. ticks. The etiological agent is Anaplasma phagocytophilum, a coccobacillary gram-negative organism with a tropism for granulocytes. Clinical manifestations include fever, partial anorexia, depression, distal limb edema, petechiation, icterus, ataxia, and reluctance to move. Hematologic changes observed are thrombocytopenia, decreased packed-cell volume and marked leukopenia involving first lymphocytes and then granulocytes. Diagnosis is based on awareness of geographic area for infection, typical clinical signs, abnormal laboratory findings, and visualization of characteristic morulae in the cytoplasm of neutrophils and eosinophils in a peripheral blood smear. Treatment consists of the administration of tetracycline. The disease is being diagnosed with increasing frequency in the United States, Canada, Brazil and northern Europe.     

A Novel Equine Hoof Lamellar Tissue Biopsy Technique

This study aims to validate the efficacy of a new device specifically developed for equine lamellar biopsy. Nine adult horses were used. Under sedation and digital nerve perineural anesthesia and after keratinized tissue thinning, a sample from the dorsal lamellar stratum was obtained using an instrument called Falcão-Faleiros' lamellotome. Hoof pain sensitivity was evaluated for 60 days, and horses were monitored for 6 months. Lateromedial radiographic images to analyze the spatial relationship between the distal phalanx and the hoof capsule were obtained before and 30 days after the biopsy. The effect of time on the variables was statistically analyzed (P < .05). On average (±SD), the biopsies produced samples that were 2.32 (±0.64) cm in length, 0.48 (±0.09) in width, and 0.51 (±0.11) cm in depth. A mean of 69 of intact primary epidermal lamellae was obtained per biopsy sample. Lameness and sensitivity to hoof testers were evident during the first 4 days postbiopsy but returned to basal levels after the fifth day. Minimal radiographic changes were observed, and the horses completely returned to their regular activities after 60 days. All biopsied hoofs grew normally during the 6-month period, making the dorsal wall defects reach the ground level. The use of the lamellotome for equine hoof lamellar biopsy produced an adequate quality and quantity of tissue for histology and allowed for full clinical recovery of the horses.     

锌和硒对动物免疫功能的影响

文章概述生命必需微量元素锌和硒对动物免疫器官的结构、生长发育和免疫细胞与免疫因子的影响 ;对体液免疫、细胞免疫和黏膜免疫功能的影响以及作用的机制 ;指出当锌和硒不足或过高时对免疫系统的不良作用。同时 ,分析了两种微量元素间的相互协同与拮抗作用 ,以及二者间交互作用对动物免疫功能的影响。从微量元素间的交互作用的动态角度进一步探讨动物营养与免疫功能的关系 ,是营养免疫学研究的新增长点 ,也是揭示营养代谢疾病发病机理的一个新的突破点 ;并将为进一步丰富动物营养免疫学理论 ,制定合理的利用微量元素新标准 ,为控制营养代谢疾病的发生等提供重要的依据