Organic acidemia in a young cat associated with cobalamin deficiency

Objective: To describe a case of severe metabolic acidosis and encephalopathy secondary to cobalamin (Cbl) deficiency in a young cat. Case summary: A 4‐year‐old spayed female domestic short hair cat weighing 2.5 kg, presented with a 2‐day history of neurological signs referable to the cerebrum. The cat was evaluated for similar episodes twice before, however, no definitive diagnosis was made for either visit. On presentation the cat was minimally responsive and had a metabolic acidosis and ketonuria with no apparent reason, such as lactic acidosis or diabetic ketoacidosis. The patient was diagnosed postmortem with an organic acidemia secondary to low Cbl levels. New or unique information provided: The purpose of this report is to alert emergency clinicians to be suspicious of an organic acidemia in any case of metabolic acidosis and ketonuria that cannot be explained. Early identification of inherited organic acidemias in domestic animals may allow prompt and appropriate treatment of these conditions.     

Long-term effect of subacute ruminal acidosis on the morphology and function of rumen epithelial barrier in lactating goats

Grain-induced subacute ruminal acidosis (SARA) impairs rumen epithelial barrier function, but it is yet to be determined if SARA can cause persistent damage to the morphology and function of the rumen epithelial barrier. The objective of the present study was to investigate if SARA has persistent effects on the morphological structure and permeability of ruminal epithelium and the expression of the genes involved in epithelial barrier function using a lactating goat model. Twelve mid-lactating Saanen goats with rumen cannulas were randomly assigned to 1 of 2 groups: control group (Ctrl, n=4) fed a basal diet with a non-fiber carbohydrate (NFC) to neutral detergent fiber (NDF) ratio of 1.40, and SARA group (SARA, n=8) fed the same basal diet but with increasing NFC to NDF ratio from 1.4 to 1.79, 2.31, and 3.23 overtime to induce SARA. At the end of the SARA challenge (post-SARA), 4 goats were randomly selected from the SARA group and fed only hay mixture adlibitum for another 4 weeks to allow for restitution (post-SARA). Ruminal pH was continuously recorded to monitor the severity of SARA. Samples of the ventral ruminal epithelium were collected after slaughter to examine the structural and functional changes of the ruminal epithelium using transmission electron microscopy (TEM), Ussing chambers, qRT-PCR, and Western bolt analyses. Compared with the Ctrl group, ruminal papilla length, width, surface area and thickness of stratum corneum increased (P<0.05), while stratum spinosum and basale thickness, and total depth of the epithelium decreased (P<0.05) in the SARA group. These changes diminished or tended to return to the levels of the Ctrl group in the post-SARA group (P>0.05). The SARA challenge also decreased cellular junction and widened the intercellular space between epithelial cells. Rumen transepithelial short-circuit current (Isc), tissue conductance (Gt), and mucosa-to-serosa flux of paracellular horseradish peroxidase (HRP) all increased (P<0.05) both in the SARA and post-SARA groups, which indicates that SARA can induce a sustained increase in epithelial permeability and barrier dysfunction. Moreover, the mRNA and protein expressions of CLDN1, OCLN and ZO-1 were down-regulated (P<0.01) in both the SARA and post-SARA groups. The results of this study showed that SARA could result in sustained epithelial barrier dysfunction, at both structural and functional levels, which is associated with decreased expression of rumen epithelial tight junction proteins, and the restitution of rumen epithelial barrier function is slower than that of its morphology.     

Immune-metabolic-inflammatory markers in Holstein cows exposed to a nutritional and environmental stressing challenge

Dairy cows are exposed to multiple stressors during the productive cycle, such as metabolic challenges, overcrowding, grouping change, environmental stress and dietary errors. Thus, it is essential to study reliable markers able to detect stress conditions in dairy farms. This study evaluates dairy cows' immunologic and metabolic markers after the sudden and combined exposition to a high-grain diet (75% concentrates) and the abrupt change of the housing system (from free stall to tie stall). A group of twenty-four Holstein cows were enrolled in a challenge study of 28 days duration. Several immunological and metabolic blood markers were evaluated over the trial. Blood samples were taken at day 0 (normal value) and day 1, 3, 7, 14, 21, and 28 (challenge). Data were submitted to a mixed model for repeated measures, including time as fixed and cows as random effects. The nutritional and environmental challenge had heavy effects on animal welfare and cows responded with a dramatic rumination drop. Our results suggest that the most responsive markers after abiotic stressors in cows were as follows: Serum Amyloid A and ROM in the acute response; Ceruloplasmin and GGT in the mid acute and Albumin, Paroxonase and FRAP in the chronic phase. Serum Amyloid A, Ceruloplasmin, Paraoxonase, GGT and ROM resulted as positive phase proteins, while, Albumin and FRAP resulted as negative phase proteins. Preliminary obtained results could concur to develop strategies able to mitigate stressor effects; moreover, the proposed design can be used as a model to test stress nutritional modulators.     

The effect of sodium butyrate supplementation on ruminal and fecal pH and serum lipopolysaccharide-binding protein after ruminal acidosis challenge in nonlactating cows

The objective of this study was to evaluate effects of sodium-butyrate supplementation on gastrointestinal function and the inflammatory response to ruminal acidosis (RA) challenge in cows. Four nonlactating cows with a rumen cannula were assigned to two treatments in a crossover design. Treatments were ruminal administration of sodium-butyrate (BUT) or control (CON). Sodium-butyrate was provided as Gustor BP70 and administered at a butyrate dose of 0.04% per kg body weight. The CON premix was made by replacing sodium-butyrate with wheat bran. Experimental periods were 28 days long with 21-day washout period separating the treatments. On Day 25 of each period, corn starch was ruminally administered at 0.7% per kg body weight as RA challenge. After RA challenge, ruminal pH was lower, and endotoxin concentration was higher for cows provided with BUT than those with CON, but the increase in fecal starch and the decrease in fecal pH were attenuated by BUT. The effect of butyrate supplementation on serum lipopolysaccharide-binding protein after RA challenge was not found. From these findings, butyrate supplementation mitigated rectal acidosis by reducing the flux of fermentable carbohydrate into the large intestine. An anti-inflammatory effect of butyrate was not observed, possibly due to lower pH and higher endotoxin concentration in the rumen.     

Anti-lipopolysaccharide antibody administration mitigates ruminal lipopolysaccharide release and depression of ruminal pH during subacute ruminal acidosis challenge in Holstein bull cattle

The effects of anti-lipopolysaccharide (LPS) antibody on rumen fermentation and LPS activity were investigated during subacute ruminal acidosis (SARA) challenge. Eleven Holstein cattle (164 ± 14 kg) were used in a 3 × 3 Latin square design. Cattle were fed a roughage diet on days −11 to −1 (pre-challenge) and day 2 (post-challenge), and a high-grain diet on days 0 and 1 (SARA challenge). For 14 days, 0-, 2-, or 4-g of anti-LPS antibody was administered once daily through a rumen fistula. Ruminal pH was measured continuously, and rumen fluid and blood samples were collected on days −1, 0, 1, and 2. Significantly lower ruminal LPS activity on day 1 was observed in the 2- and 4-g groups than those in the 0-g group. In addition, significantly higher 1-hr mean ruminal pH on SARA challenge period (days 0 and 1) was identified in the 4-g group than in the 0-g group. However, rumen fermentation measurements (total volatile fatty acid [VFA], VFA components, NH₃-N and lactic acid) and peripheral blood metabolites (glucose, free fatty acid, beta-hydroxybutyrate, total cholesterol, blood urea nitrogen, aspartate aminotransferase and gamma-glutamyl transferase) were not different among the groups during the experimental periods. Therefore, anti-LPS antibody administration mitigates LPS release and pH depression without the depression of rumen fermentation and peripheral blood metabolites during SARA challenge in Holstein cattle.     

牛瘤胃酸中毒、牛马腹泻、马类动物大肠阻塞水、电解质和酸碱失衡的研究

对１３０例牛瘤胃酸中毒、牛马原发生肠炎和消化不良腹泻及马类动物大肠阻塞临床病例进行了水、电解质和酸碱失衡研究。结果表明：马类动物大肠阻塞初期和中期病例，脱水和代谢性酸中毒发生缓慢，程度较轻，可用不加葡萄糖的口服补液盐液防治；牛马原发性肠炎和消化不良腹泻易发生脱水、代谢性酸中毒和低血Ｋ、Ｎａ、Ｃｌ，一般病例可用口服补液盐液防治，严重病例应静脉输液治疗；牛瘤胃酸中毒脱和代谢性酸中毒发展快，且严重，轻症病例可用不加葡萄糖的口服补液盐液防治，严重病例应静脉输液抢救。水、电解质和酸碱失衡的诊断应根据病种、病史、体征及化验指标综合判断。