MAGNETIC RESONANCE IMAGING FEATURES OF OBLIQUE AND STRAIGHT DISTAL SESAMOIDEAN DESMITIS IN 27 HORSES

Injury to the oblique and straight distal sesamoidean ligaments is becoming recognized as a more common cause of lameness in horses than was previously thought. The purpose of this study was to review the magnetic resonance (MR) imaging findings of 27 horses affected with desmitis of the oblique and/or straight distal sesamoidean ligament and determine long-term prognosis for horses with this diagnosis. Imaging was performed with horses in right lateral recumbency in a high-field 1 T magnet. All horses had lameness localized to the digit or metacarpophalangeal/metatarsophalangeal joint region with diagnostic local anesthetic blocks. Ten horses had forelimb lameness and 17 horses had hind limb lameness. MR imaging revealed abnormalities in the oblique distal sesamoidean ligaments in 18 horses, in the straight distal sesamoidean ligament in three horses, and in both the oblique and straight distal sesamoidean ligament in six horses. Treatment consisted of a 6-month rest and rehabilitation program in all horses. The digital flexor tendon sheath was injected with methylprednisolone acetate and hyaluronic acid in 22 horses to decrease inflammation in the injured ligaments before starting the rest and rehabilitation program. Two horses had ligament splitting performed, one in the oblique distal sesamoidean ligament and one in the straight distal sesamoidean ligament. MR imaging is an effective method for diagnosing injury to the oblique and straight distal sesamoidean ligaments in horses. Treatment, primarily a 6-month rest and rehabilitation program, allowed 76% of the horses to successfully resume performance.     

IMAGING DIAGNOSIS—VERTEBRAL CANAL PORCUPINE QUILL WITH PRESUMPTIVE SECONDARY ARACHNOID DIVERTICULUM

A 3‐year‐old Gordon Setter developed cervical hyperesthesia and a stiff gait. Upon magnetic resonance (MR) imaging, an arachnoid diverticulum was detected at the C1 level. Upon surgical resection, a porcupine quill was identified within the vertebral canal in the area of the cyst. At a retrospective review of the MR images, the quill appeared as a circular well‐demarcated T2‐hypointense lesion. Porcupine quill migrations are common in the dog but migration into the central nervous system is rare.     

牙鲆海水循环养殖系统生物膜上3种细菌的数量与代谢活性

从牙鲆(Paralichthys olivaceus)海水循环养殖系统中移动床生物滤器载体生物膜上获取异养细菌、氨化细菌和硝化细菌样本.异养细菌用平板涂布法计数,其代谢活性以培养8 h的氧吸收速率表示.氨化细菌、氨氧化细菌(AOB)和亚硝酸氧化细菌(NOB)用MPN法计数,其代谢活性分别以培养24h NH+<4>-N浓度的增加、NH+<4>-N浓度的减少和NO-<2>-N浓度的减少表示.结果表明,生物膜成熟之后,4种生理类群细菌的数量和代谢活性基本保持稳定.异养细菌数量为10-7～108CFU·m-2(载体),氨化细菌、AOB和NOB数量分别为107～108MPN·m-2(载体)、105～106MPN·m-2(载体)和105～106MPN·m-2(载体).分批培养测得异养细菌的氧吸收速率、氨化细菌的氨化速率、AOB的氨氧化速率和NOB的亚硝酸氧化速率分别是0.591～0.738g(O2)·m-2·d-1、0.081～0.135 g(Nh+4-N)·m-2.d-1、0.017～0.031 g(Nh+4-N)·m-2·d-1和0.020～0.038 g(NO-2N)·m-2·d-1.异养细菌的氧吸收速率、氨化细菌的氨化速率和AOB的氨氧化速率与异养细菌、氨化细菌和AOB的数量呈正相关.移动床生物滤器生物膜的平均氨和亚硝酸盐去除速率为(0.121±0.076)g(NH+4-N)·m-2·d-1和(0.139±0.181)g(NO-2-N)·m-2·d-1.同时测定了底物浓度和pH对氨化细菌、AOB和NOB代谢活性的影响.结果显示,氨化细菌的氨化速率、AOB的氨氧化速率和NOB的哑硝酸氧化速率与底物浓度(蛋门胨、NH+4-N和NO-2-N)呈线性相关,pH为8.0时3种生理类群细菌的代谢活性较pH6.5或pH9.5时高.[中国水产科学,2009,16(1):97-103]     

A study of neonatal cryptosporidosis of foals in New Zealand

Abstract

AIM: To assess the occurrence of Cryptosporidium oocysts in faecal specimens from foals, and investigate an outbreak of neonatal cryptosporidiosis in foals revealed in the course of the study.

METHODS: Faecal specimens from foals received by a diagnostic veterinary laboratory in New Zealand between 2006 and 2007 were submitted to Massey University and tested microscopically for the presence of Cryptosporidium oocysts. The Cryptosporidium isolates in the oocyst-positive specimens were genetically identified to species level. In addition, specimen submission data from the participating laboratory for 2005–2007 were examined. In the course of the study, the identification of one Cryptosporidium-positive specimen triggered an on-farm investigation.

RESULTS: Twelve faecal specimens submitted by the participating laboratory between 2006 and 2007 were tested further, and three were positive for C. parvum. Specimen submission records indicated a total of 67 faecal specimens were tested for Cryptosporidium by the participating laboratory between 2005 and 2007; 12 (18%) were positive. The on-farm investigation on a broodmare farm revealed a high incidence of neonatal diarrhoea in foals; C. parvum was the only enteropathogen found in the faeces of 4/4 affected foals examined. The diarrhoea in all those foals was self-limiting, manifesting during the second week of life, resembling foal heat diarrhoea, and accompanied by a short but intense period of shedding oocysts.

CONCLUSIONS AND CLINICAL RELEVANCE: The fact that Cryptosporidium parasites were identified in 18% of faecal specimens from foals analysed for this agent in 2005–2007 by the participating laboratory indicated that infection with this agent in foals is not uncommon.

Collectively, the results of this and previous studies performed in New Zealand indicate C. parvum is a cause of diarrhoea in newborn foals, potentially accounting for a proportion of cases empirically diagnosed as foal heat diarrhoea. It is therefore advisable to take precautions when handling diarrhoeic foals, until this potentially zoonotic agent is ruled out in the laboratory.     

Fibrin–alginate hydrogel supports steroidogenesis,in vitro maturation of oocytes and parthenotes production from caprine preantral follicles cultured in group

This study aimed to establish a culture system that improves the in vitro development of caprine preantral follicles. In a first experiment, follicles were encapsulated as a single unit per bead and cultured singly or in groups or with five follicles in the same alginate (ALG) bead for 18 days. In a subsequent experiment, the “five follicles per bead” design was chosen to culture in ALG, fibrin–alginate (FA) or hyaluronate (HA) for 18 days. In a third experiment, we chose the five follicles per bead in FA to culture for 30 days. The culture set‐up of five follicles per ALG bead increased antrum formation and follicle diameter compared to the other culture designs (p < .05). Moreover, under this condition, 44.44% of the oocytes from in vitro cultured preantral follicles reached meiotic resumption. A significant increase of follicle diameter occurred in attachment system and FA (p < .05), but the ALG condition reached the highest among all groups on day 18 (p < .05). Follicles encapsulated in matrix produced more estradiol and progesterone than attachment system (p < .05). The expression of MMP‐9 mRNA was higher in FA than in other groups (p < .05) and similar to antral follicles from in vivo control (p > .05). Only FA group resulted in oocytes matured. After 30 days, oocytes from preantral follicles in vitro grown in FA developed to eight‐cell parthenotes. In conclusion, a culture system using FA supported the development of caprine preantral follicles cultured in group and included in the same bead of hydrogel, improving the oocyte maturation and producing parthenotes.     

PROTON SPOT SCANNING RADIOTHERAPY OF SPONTANEOUS CANINE TUMORS

Thirty dogs with spontaneous tumors were irradiated with proton therapy using a novel spot scanning technique to evaluate the safety and efficacy of the system, and to study the acute and late radiation reactions. Nasal tumors, soft tissue sarcomas, and miscellaneous tumors of the head were treated with a median total dose of 52.5 Gy given in 3.5 Gy fractions. Acute effects, late effects, tumor response, and outcome were analyzed. No unexpected radiation reactions were seen, however two dogs did develop in-field osteosarcoma, and one dog developed in-field bone necrosis. Complete response to therapy was seen in 40% (12/30), partial response in 47% (14/30), and no response in 13% (4/30). Median survival for all dogs was 385 days (range of 14–4583 days). Dogs with nasal cavity tumors had a median survival of 385 days (range of 131–1851 days) and dogs with soft tissue sarcomas had a median survival time of 612 days (range of 65–4588 days). Treatment outcome was similar to historical controls. This new proton spot scanning technique proved to be safe and reliable.     

MAGNETIC RESONANCE IMAGING FINDINGS IN HORSES WITH RECENT ONSET NAVICULAR SYNDROME BUT WITHOUT RADIOGRAPHIC ABNORMALITIES

Seventy-two horses with recent onset of navicular syndrome and normal radiographs were assessed. Horses underwent magnetic resonance (MR) imaging of both front feet. All abnormalities were characterized and the most severe abnormality identified, if possible. Abnormal signal intensity in the navicular bone was the most severe abnormality in 24 (33%) horses. Pathologic change in the deep digital flexor tendon was the most severe abnormality in 13 (18%) horses. Pathologic change in the collateral sesamoidean ligament was the most severe abnormality in 11 (15%) horses. Pathologic change in the distal sesamoidean impar ligament was the most severe abnormality in seven (10%) horses. Multiple abnormalities were observed in 13 (18%) horses in which an abnormality that was more severe than the others could not be determined. Abnormalities were not observed in the navicular bone or its supporting soft tissues in four (5%) horses. Fifty-six horses had abnormalities that were most severe in one limb; in 52 (93%) horses, the most severe abnormalities were in the foot of the most lame limb. In 7% (4/56) of horses, the most severe findings were in the opposite limb, and in 16 horses, the findings on both limbs were similar. MR imaging is a useful technique for evaluating horses with navicular syndrome and can differentiate between multiple abnormalities. This provides a more specific diagnosis which affects further treatment of the horse. Pathologic changes in different locations in the foot can cause similar clinical signs that, before MR imaging, were categorized as one syndrome.