Objective—To characterize the magnitude and duration of the antibody response against human albumin (HA) in critically ill and healthy dogs.
Design—Cohort and cross-sectional study.
Animals—Fourteen critically ill dogs that received 25% HA as part of their treatment protocol, 2 healthy dogs with no known previous exposure to HA that received 2 infusions of 25% HA (positive control dogs), and 47 healthy dogs and 21 critically ill dogs with no known exposure to HA (negative control dogs).
Procedures—An ELISA to detect IgG against HA was developed. Serum samples were obtained from the critically ill dogs prior to infusion of HA, at the time of hospital discharge, and 4 to 6 weeks and 6 months after HA administration. Serum samples were obtained at 2- to 4-week intervals from both positive control dogs for 101 weeks. A single serum sample was obtained from each of the negative control dogs.
Results—All 14 critically ill dogs developed serum IgG against HA. Peak antibody response was detected 4 to 6 weeks after HA administration. In both positive control dogs, IgG against HA was detected 10 days after HA administration and continued past 97 weeks. The peak antibody response was detected at 3 weeks in 1 dog and at 9 weeks in the other. Five of the 68 (7%) negative control dogs had a positive antibody response.
Conclusions and Clinical Relevance—Results suggested that dogs developed a pronounced IgG response following exposure to HA and that some dogs with no history of HA administration were positive for anti-HA IgG.
To evaluate the reticulorumen pH of beef feedlot steers throughout the feeding period and to assess the association between the respective durations that the reticulorumen pH was ≤ 5.6 (subacute ruminal acidosis) and ≤ 5.2 (acute ruminal acidosis) and liver abscess severity.
59 feedlot steers (mean body weight, 349.5 kg).
On day 0, each steer was orally administered an electronic bolus that monitored the reticulorumen pH every 10 minutes for 150 days. Steers were transitioned from a starter to intermediate ration on day 8 (transition 1) and from the intermediate to finish ration on day 19 (transition 2). The ration carbohydrate and megacalorie contents increased with each transition. During each transition, the lower megacalorie ration was fed at the 8:00 AM feeding and the higher megacalorie ration was fed at the 2:00 PM feeding for 3 days before the higher megacalorie ration was fed extensively. Steers were sent to slaughter after 182 days; each carcass was assessed for liver abscesses.
The diurnal reticulorumen pH pattern was characterized by a peak at 7:00 AM and nadir at 8:00 PM. The mean percentages of time that the reticulorumen pH was ≤ 5.6 and ≤ 5.2 were more than 10-fold greater during transition 1, compared with during transition 2, and were significantly greater for steers with extensive liver abscesses than for steers without extensive liver abscesses.
CONCLUSIONS AND CLINICAL RELEVANCE
Efforts to minimize the duration that the reticulorumen pH is ≤ 5.6 might mitigate liver abscess formation in feedlot cattle.
Case Description—6 healthy dogs given human albumin solution as part of a study were examined following development of an immediate hypersensitivity reaction (1 dog) and signs suggestive of a type III hypersensitivity reaction (all 6 dogs).
Clinical Findings—All 6 dogs were healthy prior to administration of human albumin solution. One dog developed signs of an immediate hypersensitivity reaction, characterized by vomiting and facial edema, during administration of human albumin solution. All 6 dogs developed signs of a delayed adverse reaction 5 to 13 days after administration of human albumin solution. Initial clinical signs included lethargy, lameness, edema, cutaneous lesions indicative of vasculitis, vomiting, and inappetance.
Treatment and Outcome—In the dog with signs of immediate hypersensitivity, signs resolved after administration of human albumin solution was discontinued and diphenhydramine was administered. Supportive treatment was provided after dogs developed signs of a delayed adverse reaction. Four dogs recovered, but 2 dogs died despite treatment. All 6 dogs were found to have antihuman albumin antibodies. There was no evidence of contamination of the human albumin solution.
Clinical Relevance—Findings suggest that administration of human albumin solution in healthy dogs with normal serum albumin concentrations may result in signs of a type III hypersensitivity reaction.