Association between uterine disease and indicators of neutrophil and systemic energy status in lactating Holstein cows.

The objective of this study was to evaluate the association between uterine disease and indicators of neutrophil (PMN) and systemic energy status in dairy cows. Peripheral blood (120 mL) was collected weekly from 84 Holstein cows for PMN isolation and plasma collection from calving until 42 d in milk (DIM). The final analysis included 80 cows. Of those, 20 cows were classified as having metritis (fetid uterine discharge and fever), 15 as having subclinical endometritis (SCE; >or=10% PMN on uterine cytology), and 45 as healthy controls. Plasma haptoglobin concentration was increased only in cows that developed metritis. Neutrophil glycogen content was reduced in cows developing metritis compared with healthy cows on the day of calving and at 7 and 42 DIM. Cows with SCE had lower PMN glycogen content than healthy cows at 7, 28, and 42 DIM. Blood glucose was affected by disease status within parity. Primiparous metritis cows had greater blood glucose concentrations than healthy primiparous cows. Multiparous metritis cows tended to have lower blood glucose concentration than multiparous SCE cows. Cows that developed metritis and SCE had or tended to have greater NEFA and BHBA than healthy cows, mainly around calving. At calving, cows that developed metritis had higher plasma estradiol concentration than healthy cows and greater plasma cortisol than cows that had SCE. Plasma insulin was not affected. Plasma glucagon was increased for SCE cows. Cows that developed uterine disease experienced a greater degree of negative energy balance and had decreased lower intracellular PMN glycogen levels, which could be a major predisposing factor for disease because of decreased availability of oxidative fuels.

Acid-base balance and ventilation during sternal and lateral recumbency in field immobilized black rhinoceros (Diceros bicornis) receiving oxygen insufflation: a preliminary report.

Posture, ventilation, and acid-base balance using auricular venous blood values (pH, lactate, base excess [BE], HCO(3)(-), PO(2), SO(2), and PCO(2)), oxygen saturation of hemoglobin (SpO(2)), and end-tidal carbon dioxide (P(ET)CO(2)) were compared between sternal (STE) and lateral (LAT) recumbency in free-ranging black rhinoceros (Diceros bicornis bicornis) receiving oxygen insufflation. Data are reported as median, minimum, and maximum (median [minimum, maximum]). Thirty-six desert-adapted black rhinoceros (20 male, 16 female; age 8 [1.5, 33] yr) were immobilized in Namibia in March and April of 2008, from a helicopter, by remote intramuscular injection with etorphine HCl, azaperone, and hyaluronidase. Time from darting to recumbency was 6.0 (3, 15.5) min. Data were organized into two sampling periods: sample period 1 (P1, collected within 0-20 min postdarting; 13 [6.5, 19] min) and sample period 2 (P2, collected between 20-40 min postdarting; 32 [22.3, 39] min). All animals were acidemic (pH 7.24 [7.07, 7.32]) and hypoxemic (PO(2) 51 [38, 95.2]; SO(2) 78 [64, 96] mmHg) after capture. Lactate at P1 was 7.2 (3.2, 16.8) mmol/l and decreased (P=0.01) to 4.6 (1.2, 10.9) mmol/l at P2. At P2, lactate was less (P=0.06) in LAT 3.5 (1.2, 8.6) mmol/l than in STE posture 7.4 (3.1, 10.9) mmol/l. In P2, PO(2), SO(2), and SpO(2) were higher (P=0.02, 0.10, and 0.01, respectively) in STE than in LAT. End-tidal carbon dioxide in LAT was 38 (26, 47) mmHg and increased (P<0.001) rapidly to 48 (37, 55) mmHg when animals were moved into STE; no corresponding change in PCO(2) was observed. These preliminary findings suggest that STE posture in recumbent black rhinoceros reduces dead-space ventilation and improves oxygenation. Lateral posture was associated with lower blood lactate, quicker lactate recovery, or both. It is possible that the posture of recumbent rhinoceros after capture affects lactate accumulation and clearance, or both, and procedures should consider positioning in order to enhance perfusion.

Equine herpesvirus-1 consensus statement.

Equine herpesvirus-1 is a highly prevalent and frequently pathogenic infection of equids. The most serious clinical consequences of infection are abortion and equine herpesvirus myeloencephalopathy (EHM). In recent years, there has been an apparent increase in the incidence of EHM in North America, with serious consequences for horses and the horse industry. This consensus statement draws together current knowledge in the areas of pathogenesis, strain variation, epidemiology, diagnostic testing, vaccination, outbreak prevention and control, and treatment.

Comparison of the efficacy of inactivated combination and modified-live virus vaccines against challenge infection with neuropathogenic equine herpesvirus type 1 (EHV-1).

Equine herpesvirus type 1 (EHV-1) is a ubiquitous alphaherpesvirus of horses which causes rhinopneumonitis, abortion and myeloencephalopathy. To test the efficacy of commercial vaccines in protection against neurological EHV-1 challenge, groups of five horses were immunized with modified-live virus or an inactivated vaccine, or received placebo. Horses were challenged by aerosol with a recent virus isolate obtained from a case of paralytic EHV-1. The duration of fever decreased significantly in the modified-live virus vaccine group. Three animals in each of the inactivate and control groups showed alterations in neurological status. When compared to the inactivated vaccine, the modified-live virus vaccine induced significantly lower virus-neutralizing antibodies over the course of the study. The modified-live virus vaccine resulted in low EHV-1-specific IgG(T)/IgGa and IgG(T)/IgGb ratios, suggesting a bias towards a cytotoxic immune response. Virus shedding from the nasopharynx was almost undetectable in the modified-live virus group, and was significantly lower when compared to that in the other groups. Normalized lymphocyte viral genome copies were similar for the three groups, although animals vaccinated with the modified-live virus vaccine were qPCR-positive on fewer days when compared to those of the other groups. Based on data from neurological signs, rectal temperatures, virus isolation from nasal swabs and immune response specificity, we concluded that protection induced by the modified-live virus vaccine is superior to that induced by the inactivated combination vaccine.

Inhibition of lymphocyte proliferation and activation: a mechanism used by equine invasive trophoblast to escape the maternal immune response.

At days 36-38 of gestation, the equine invasive trophoblast cells migrate into the endometrium of the pregnant mare to form the endometrial cups. During their migration, they become surrounded by maternal CD4+ and CD8+ T lymphocytes, and stimulate a cytotoxic antibody response to the paternal major histocompatibility complex class I antigens that they express. Nevertheless, endometrial cup cells remain viable at the site of uterine invasion up to days 80-100 of gestation, suggesting the participation of immunomodulatory mechanisms to the maternal cellular immune response. To determine the effects of the invasive trophoblast cells on lymphocyte proliferation, an in vitro co-culture system was developed using isolated equine invasive trophoblast cells and peripheral blood lymphocytes. Fetal fibroblast cells from the same conceptuses were used as controls. The presence of invasive trophoblast cells or their pre-conditioned medium inhibited 50% or more of lymphocyte proliferation, while fetal fibroblasts had no effect. The invasive trophoblast cell inhibitory factor needed to be present constantly to affect lymphocyte proliferation, and it was ineffective if lymphocytes had been previously stimulated to proliferate. The lymphoproliferative inhibitory mechanism affected lymphocyte subpopulations similarly. In addition, lymphocyte expression of cytokine mRNA including IFNgamma, IL-2, IL-4, and IL-10 was affected compared to controls. The implication of these observations in vivo may explain, in part, the apparent equine maternal immune acceptance of the presence and development of endometrial cup cells.

Serum IgM concentrations in normal, fit horses and horses with lymphoma or other medical conditions.

The purposes of this study were to (1) prospectively establish serum IgM and IgG concentrations in normal, fit, adult horses over time and (2) determine the accuracy of serum IgM concentrations for diagnosing lymphoma. Serial IgM and IgG concentrations were measured with a radial immunodiffusion assay in 25 regularly exercised horses at 6-week intervals. Horses had serum IgM concentrations ranging from 50 to 242 mg/dL over 5 months, with 20% of horses having IgM < or = 60 mg/dL. The normal range for IgM in fit horses should be considered 103 +/- 40 mg/dL and a cut-point for an IgM deficiency, < or = 23 mg/dL. IgG concentrations ranged from 1,372 to 3,032 mg/dL. Retrospectively, medical records of adult horses (n = 103) admitted to the Cornell University Hospital for Animals for which serum IgM was measured were examined. Horses were categorized as "lymphoma negative" (n = 34) or "lymphoma positive" (n = 18). The sensitivity and specificity of a serum IgM concentration (< or = 60 mg/dL) for detecting equine lymphoma was 50 and 35%, respectively. At the new cut-point (< or = 23 mg/dL), the sensitivity was low at 28% and the specificity improved to 88%. The negative predictive values at various population prevalences indicate that a horse with a high serum IgM (> 23 mg/dL) is unlikely to have lymphoma, whereas the positive predictive value (70%) does not allow for reliable determination of lymphoma in a horse with serum IgM < or = 23 mg/dL. Therefore, serum IgM concentrations should not be used as a screening test for equine lymphoma.

Simultaneous flow cytometric analysis of phagocytosis and oxidative burst activity in equine leukocytes.

This paper describes a method for simultaneously measuring phagocytosis and oxidative burst activity in equine peripheral blood leukocytes by flow cytometry. Opsonized propidium iodide-labelled Staphylococcus aureus (PI-Sa) was used to measure the uptake of bacteria by equine phacocytes and the oxidative burst activity by oxidation of dihydrorhodamine 123. The requirements to achieve optimal activity of phagocytosis and oxidative burst are described. The advantage of the simultaneous technique is that it provides both independent and comparative values for phagocytosis and the oxidative burst, for the detection of impaired mechanisms of microbial destruction. Furthermore, the technique allows evaluation of opsonization activity in this context.