奶牛胃肠道菌群与奶牛乳房炎关联性及其对乳房炎调控潜力的研究进展

乳房炎是严重影响奶牛机体健康状态及乳品质量的疾病之一。一直以来,外源致病菌入侵乳房并引发感染被认为是奶牛乳房炎发病的主要因素。然而,最近的研究表明,胃肠道菌群同样能够影响奶牛乳房炎的发病并对炎症进行调控。其主要机制可能涉及"肠道-乳腺"内源途径,即来自胃肠道的某些细菌可以通过涉及单核免疫细胞（主要是吞噬细胞）机制进行转移,通过内源性细胞途径（细菌性肠-乳途径）迁移到乳腺。本文就奶牛乳房炎的致病因素及其影响、胃肠道菌群与奶牛乳房炎的关联性及其对乳房炎的调控（包括饮食、短链脂肪酸（short-chain fatty acids,SCFAs）、益生菌及共生菌等因素）等方面进行了综述,旨在为奶牛乳房炎的发病机制及缓解措施提供新的思路。     

犬慢性肾衰竭进程中肠道菌群代谢物短链脂肪酸水平的变化及其对肾功能的影响

本研究旨在评估短链脂肪酸在慢性肾衰竭患犬和健康犬中的水平,探究短链脂肪酸变化的原因及其对肾功能的影响。选取22例轻度慢性肾衰患犬（M-CRF组）、29例重度慢性肾衰患犬（S-CRF组）和26例健康对照犬（HC组）,用16S rDNA测序技术分析肠道菌群多样性,气相色谱法检测粪中短链脂肪酸浓度。通过粪菌移植和补充丁酸钠给5/6肾摘除犬,观察肠道菌群及丁酸钠对肾功能影响。结果显示：1）S-CRF组肠道菌群多样性指标观察物种数及Simpson指数低于HC组（P<0.05）,PCoA分析显示,S-CRF组肠道菌群与M-CRF、HC组有差异。2）LEfSe分析显示,S-CRF组和HC组间大量差异菌群,拟杆菌科、拟杆菌属及假单胞菌科等7个菌种富集于S-CRF组,普氏杆菌科、梭菌科、普氏杆菌属及普拉梭菌属等11个菌种富集于HC组。CCA分析发现富集于S-CRF组菌种丰度与肾功能指标呈正相关。3）S-CRF组粪中乙酸、丙酸及丁酸浓度均显著低于HC组和M-CRF组,M-CRF组丁酸浓度显著低于HC组（P<0.05）,且丁酸浓度与血中胱抑素C（Cys-c）、肌酐（Cr）及尿素氮（BUN）等肾功能指标呈负相关（r值分别为-0.451、-0.583和-0.514,P<0.01）。4）与慢性肾衰模型组（5/6 Nx组）比较,慢性肾衰犬给与丁酸钠8周后,血清Cr和BUN显著降低（P<0.05）;粪菌移植8周后,血清Cr和BUN显著升高（P<0.05）,丁酸钠可回调血清Cr和BUN水平。综上表明,慢性肾衰竭患犬肠道菌群多样性降低,菌群结构及丰度改变,粪中短链脂肪酸浓度降低,这些变化可加剧肾功能障碍。为犬慢性肾衰竭的防治提供新的理论依据。     

Platelet abnormalities and platelet-to-lymphocyte ratios in canine immunosuppressant-responsive and non-responsive enteropathy: A retrospective study in 41 dogs

Few studies have examined platelet alterations in dogs with chronic enteropathy. Our aim was to investigate platelet count (PLT), mean platelet volume (MPV), and platelet-to-lymphocyte ratio (PLR) in dogs diagnosed with immunosuppressant-responsive enteropathy (IRE). In this retrospective study of 41 dogs, data regarding signalment, canine chronic enteropathy clinical activity index (CCECAI), endoscopic and histopathological scores, PLT, MPV, PLR, total serum protein concentrations, albumin, and iron were collected. Clinical response and relapse were assessed with the evaluation of CCECAI over time. One month after starting therapy, dogs with >25% CCECAI reduction were considered responders. During a three-month CCECAI evaluation as part of a twelve-month follow-up, a CCECAI >3 together with a ≥2 unit increase in responder dogs was considered a relapse. PLT and PLR displayed significant negative correlation with MPV. MPV was positively correlated with total protein and albumin levels and negatively correlated with CCECAI. Three dogs were classified as non-responders, and 14 relapsed within 12 months. No differences were observed in PLT, MPV, or PLR between responding/non-responding and relapsing/non-relapsing groups. PLT, MPV, and PLR correlated with total protein, albumin, and CCECAI, confirming PLT as a potential marker, and suggesting MPV as a new marker of clinical efficacy against canine IRE.     

In-hospital development of an aorto-cardiac fistula in a Warmblood gelding with chronic renal disease

A 20-year-old Warmblood gelding presented for evaluation and treatment of ventral oedema and azotaemia of unknown aetiology. On presentation, a diastolic heart murmur was appreciated and echocardiography revealed moderate aortic insufficiency due to chronic degenerative valve disease. The horse was hospitalised and failed to respond to oral and i.v. fluids and diuretics. Following discontinuation of all fluid and diuretic therapy, the horse became acutely agitated and developed monomorphic ventricular tachycardia. The ventricular tachycardia spontaneously converted to normal sinus rhythm, however the heart murmur changed in timing to a right basilar continuous murmur and bounding jugular pulses were noted. Repeat echocardiogram revealed an aorto-cardiac fistula with dissection into the basilar interventricular septum and left-sided chamber volume overload that was not previously present. Attempts at stabilisation were unsuccessful and euthanasia was elected. Post-mortem examination confirmed chronic renal disease of unknown aetiology in addition to an aorto-cardiac fistula originating from the right sinus of Valsalva with subsequent dissection into the basilar interventricular septum.     

Diagnosis and treatment of mastitis in mares

Infection and inflammation of the udder (mastitis) is a common condition affecting all domestic mammals, but it appears to be less prevalent in mares than in dairy cows and dairy goats. The seemingly reduced incidence of mastitis in mares can be partially explained by the smaller size and relatively concealed location of the mare’s udder, coupled with a smaller storage capacity than cows and goats. Mastitis can affect lactating, peripartum, dry mares, mares at dry-off or prepubertal foals. Common clinical signs include swollen mammary tissue, abnormal mammary gland secretion, fever and anorexia; less common signs are hindlimb lameness and a swollen mammary vein. On rare occasions, mastitis pathogens can severely affect the nursing foal and mares may develop fibrotic tissue and consequent agalactia in the side(s) or quarter(s) affected. Based on the clinical presentation, mastitis can be classified as acute or chronic, and clinical or subclinical. Diagnosis is based on the clinical signs aided with aerobic culture and cytological evaluation of the gland secretion. In addition, these ancillary tests can also be used to assess prognosis and duration of treatment. Mares suffering from mastitis may present neutrophilia and hyperfibrinogenaemia. Treatment for mastitis includes antimicrobial therapy (systemic and/or locally), nonsteroidal anti-inflammatory drugs, frequent milking and cold hosing with/without hot-packing applied on the gland. While the frequent monitoring of mares after weaning and reducing food intake should be part of common practices at weaning, cleaning of the udder, control of insect populations and frequent milking of mares with a foal unable to nurse can also aid in preventing mastitis.     

Effect of relationships among clinical mastitis incidence,reproductive performance,and culling rate on the lifetime of dairy cows at Hiroshima University Farm

Farm managers' decision to cull dairy cows is based on the cows' milk production, history of disorder(s), and reproductive performance, each of which affects dairy cows' lifetime (herd life and productive lifespan). We investigated the relationships among the incidence of clinical mastitis (CM), the reproductive performance, and the culling rate. We also assessed the effects of these relationships on the lifetimes of dairy cows, using the records made before and after the introduction of an automatic milking system (AMS) at Hiroshima University Farm. Milk yield, CM incidence density, and culling rate of dairy cows increased after the AMS introduction. The CM incidence was associated with an elongation of the calving interval in cows with the same parity. CM in the 1st parity might have caused the reductions of the cows' lifetime and their parity at culling. A higher age at first calving (AFC) was associated with an increase in culling rate but did not lead to a significant decrease in lifetime. Investigations of the factors mediating CM in the 1st parity or AFC with CM incidence or culling rate in the later stages might contribute to the control of lifetime of dairy cows.