Dusty W. Nagy

Effect of colostral volume, interval between calving and first milking, and photoperiod on colostral IgG concentrations in dairy cows

OBJECTIVE To identify cow and management factors associated with colostral IgG concentration in dairy cows. DESIGN Prospective observational study. ANIMALS 81 multiparous Holstein-Friesian cows from a single herd. PROCEDURES Serum was obtained at the start of the nonlactating period, and cows were assigned to 1 of 4 photoperiod groups: natural day length (n = 22 cows), long days (16 h of light/d [21]) or short days (8 h of light/d [20]) for the entire nonlactating period, or natural day length followed by short days for the last 21 days of the nonlactating period (18). Serum and colostrum were collected at the first milking after calving. Regression analysis was used to investigate associations between colostral IgG concentration and the interval between calving and first milking, colostral volume, photoperiod, length of the nonlactating period, and season of calving. RESULTS Colostral IgG concentration decreased by 3.7% during each subsequent hour after calving because of postparturient secretion by the mammary glands. The interval between calving and first milking and the colostral volume were significantly and negatively associated with colostral IgG concentration, with the former effect predominating. Photoperiod had no effect on colostral IgG concentration or volume. Serum protein concentration at calving correlated poorly with colostral IgG concentration. CONCLUSIONS AND CLINICAL RELEVANCE Dairy producers should harvest colostrum as soon as possible after calving to optimize transfer of passive immunity in neonatal calves. Photoperiod can be manipulated without adversely affecting colostral IgG concentration.

Resuscitation and Critical Care of Neonatal Calves

Neonatal morbidity and mortality are major economic concerns in both beef and dairy cattle in the United States. In both beef and dairy most calf death occurs in the early neonatal period, particularly in calves born following dystocia. This article focuses on the resuscitation of calves after delivery and highlights some therapeutic points for the care of critical calves.

Evaluation of factors affecting serum IgG concentrations in bottle-fed calves.

OBJECTIVE To determine the effect of time interval from birth to first colostrum feeding on colostrum intake and serum IgG concentration and the effect of varying colostral volume intake and colostral IgG concentration on the probability of failure of passive transfer (FPT) in bottle-fed calves. DESIGN Randomized controlled study. ANIMALS 104 calves. PROCEDURES Equal numbers of calves were randomly assigned to groups and fed 3 L of their dams colostrum at 1, 2, 3, or 4 hours after birth by use of a nipple bottle. Calves were allowed to feed for 15 minutes, and intake was recorded. A second 3-L bottle feeding of colostrum was offered at 12 hours of age. RESULTS 17.2% of calves ingested 3 L of colostrum at the first feeding and 3 L at 12 hours of age. Calf age, up to 4 hours, had no significant effect on the calfs ability to ingest colostrum or on 48-hour serum IgG concentration. Colostral intake at 1, 2, 3, or 4 hours had no effect on intake at the second feeding. Probability of FPT in calves ingesting 3 L at both feedings was < 0.05. CONCLUSIONS AND CLINICAL RELEVANCE Allowing calves fed by nipple bottle to ingest as much colostrum as they can within 4 hours after birth and at 12 hours of age substantially reduced the probability of FPT. Bottle-fed calves that do not ingest 3 L of colostrum within the first 4 hours after birth should be targeted for oroesophageal intubation.

Frequency of detectable serum IgG concentrations in precolostral calves.

OBJECTIVE To determine the prevalence of detectable serum IgG concentrations in calves prior to ingestion of colostrum and to assess whether a detectable IgG concentration was related to dam parity, calf birth weight, calf sex, season of calving, or infectious agents that can be transmitted transplacentally. ANIMALS 170 Holstein dairy calves. PROCEDURES Serum samples were obtained from calves prior to ingestion of colostrum, and serologic testing for bovine viral diarrhea virus (BVDV) and Neospora caninum was performed. Relative risk, attributable risk, population attributable risk, and population attributable fraction for calves with a detectable serum IgG concentration attributable to positive results for N caninum and BVDV serologic testing were calculated. Logistic regression analysis was used to determine whether dam parity, calf sex, season of calving, and calf weight were associated with precolostral IgG concentration. RESULTS 90 (52.9%) calves had a detectable total serum IgG concentration (IgG >or= 16 mg/dL). Relative risk, attributable risk, population attributable risk, and population attributable fraction for calves with a detectable serum IgG concentration attributable to positive results for N caninum serologic testing were 1.66, 0.34, 0.014, and 0.03, respectively. Calf sex, calf birth weight, and season of calving were not significant predictors for detection of serum IgG in precolostral samples. CONCLUSIONS AND CLINICAL RELEVANCE Prevalence of IgG concentrations in precolostral serum samples was higher than reported elsewhere. There was no apparent link between serum antibodies against common infectious agents that can be transmitted transplacentally and detection of measurable serum IgG concentrations.

Diagnostics and Ancillary Tests of Neurologic Dysfunction in the Ruminant

A variety of diagnostic tests can be used to help further characterize and diagnose neurologic disease in ruminant species. Cerebrospinal fluid is easily collected, and analysis can help in defining the broad category of disease. Diagnostic imaging, including radiography, myelography, ultrasonography, computed tomography, and MRI, have all been used to varying degrees in ruminants. Advanced cross-sectional imaging techniques have the capacity to aid greatly in diagnosis, but their cost can often be prohibitive. Currently, electrodiagnostic tests are not well evaluated or used in the diagnosis of neurologic disease in ruminants.

Successful management of severe hypoventilation and hypercapnia in an alpaca (Vicugna pacos) with short-term mechanical ventilation.

OBJECTIVE To describe the successful management of an alpaca with severe hypoventilation and hypercapnia, suspected to be secondary to an anesthesia-related event. CASE SUMMARY A 3-year-old, female alpaca underwent a routine eye enucleation under general anesthesia after traumatic globe perforation. Severe hypoventilation and associated hypercapnia developed postoperatively resulting in a severe primary respiratory acidosis. The awake alpaca was supported with positive-pressure ventilation for approximately 20 hours before successful weaning. Recovery to hospital discharge occurred over the subsequent 5 days with the alpaca regaining apparently normal respiratory function. NEW OR UNIQUE INFORMATION PROVIDED To the knowledge of the authors, this is the first report describing positive-pressure ventilation of an alpaca in the veterinary literature. In this case of severe hypoventilation, ventilatory support was essential to the positive outcome. As South American camelids continue to increase in popularity there may be an increased demand for high-quality and sophisticated veterinary care for these animals. Mechanical ventilation can be used to help restore and maintain normal PO2, PCO2, and respiratory acid-base status in alpacas with ventilatory dysfunction.

Cutaneous mast cell tumour and renal tubular adenocarcinoma in a Vietnamese potbellied pig

The occurrence of neoplasia in pigs is relatively rare. Infrequent cases of cutaneous mast cell tumours have been reported, and there have been no reports of renal tubular adenocarcinomas in this species. The current communication describes an 18-year-old Vietnamese potbellied pig with renal and cutaneous mast cell tumours and a renal tubular adenocarcinoma. Grossly, there were fluid-filled cysts in the kidneys and white-tan nodules on the skin and in the renal parenchyma. Histopathology revealed focally extensive masses of round cells in the skin and kidney. Tryptase and c-kit immunohistochemistry confirmed a diagnosis of mast cell tumour in cutaneous tissue. A second renal mass contained a dense cellular mass of erratically arranged tubules lined by layers of cuboidal epithelial cells, consistent with a renal tubular adenocarcinoma. These two types of neoplasia have rarely been reported in the literature alone and have never been reported concurrently in the same animal.

Immune complex glomerulonephritis of suspected iatrogenic origin in five Japanese Black calves

Five Japanese Black embryo transfer calves from a single embryo flush, 30 to 45-days-old, including 4 live animals for clinical examination and 1 dead for necropsy, were presented with a history of decreased milk intake and hypoproteinemia. Consistent clinicopathological abnormalities in the 4 calves presented for clinical evaluation included hyperkalemia, hyperphosphatemia, hypoproteinemia, hypoalbuminemia, hyperbilirubinemia, increased creatine phosphokinase activity, and proteinuria. Four calves ultimately were necropsied and all had histologic evidence of immune complex glomerulonephritis. Glomerulonephritis in these calves was hypothesized to have resulted from the interaction of passively acquired antibodies at birth and active immunization at 7 and 28 days of age with a Salmonella Typhimurium core antigen vaccine.

Use of cecal bypass via side-to-side ileocolic anastomosis without ileal transection for treatment of ileocecal intussusception in a Vietnamese pot-bellied pig (Sus scrofa)

CASE DESCRIPTION A 5-year-old castrated male Vietnamese pot-bellied pig (Sus scrofa) was evaluated because of anorexia, vomiting, diarrhea, and weight loss. CLINICAL FINDINGS Hypermotile gastrointestinal sounds were noted on abdominal auscultation. An inflammatory leukogram, dehydration, prerenal azotemia, hyponatremia, hypochloremia, hyperproteinemia, hyperglobulinemia, hypomagnesemia, and high γ-glutamyl transpeptidase activity were identified. Transabdominal ultrasonography revealed distended loops of small intestine. TREATMENT IV fluid therapy and analgesic treatment were unsuccessful in the resolution of clinical signs. Exploratory laparotomy revealed an ileocecal intussusception involving the distal portion of the ileum. Distal ileal and cecal bypass were achieved via side-to-side anastomosis of the proximal portion of the ileum and spiral colon with a gastrointestinal anastomosis stapler. Ileal transection or occlusion was not performed. Postoperative complications were minimal, and the pig was clinically normal 15 months after surgery and required no special care or diet. CLINICAL RELEVANCE Distal ileal and cecal bypass without ileal transection have not been described previously in Vietnamese pot-bellied pigs. Anastomosis of the proximal portion of the ileum to the spiral colon without major complications represents a novel, technically simple approach to bypass of the distal portion of the ileum and cecum.