Search Results

Abstract

Objective—To compare 4 assay procedures for prediction of passive transfer status in lambs.

Animals—Thirty-one 1-day-old Sardinian lambs.

Procedure—Serum IgG concentration was determined by use of single radial immunodiffusion. The following were determined: serum total protein concentration as measured by refractometry (ie, refractometry serum total protein concentration), serum total protein concentration as determined by the biuret method (ie, biuret method serum total protein concentration), serum γ-globulin concentration as determined by serum protein electrophoresis, and serum γ-glutamyltransferase (GGT) activity as measured by spectrophotometry. Accuracy of these assays for estimation of serum IgG concentration in 1-day-old lambs was established by use of linear regression analysis.

Results—Refractometry serum total protein concentration, biuret method serum total protein concentration, and serum γ-globulin concentration were closely and linearly correlated with serum IgG concentration. The natural logarithm (ln) of serum GGT activity was closely and linearly correlated with serum IgG concentration (ln). Refractometry serum total protein concentration, biuret method serum total protein concentration, and γ-globulin concentration accounted for approximately 85%, 91%, and 95% of the variation in serum IgG concentration, respectively. Serum GGT activity (ln) accounted for approximately 92% of the variation in serum IgG concentration (ln).

Conclusions and Clinical Relevance—For prediction of passive transfer status in 1-day-old lambs, serum GGT activity or biuret method serum total protein concentration determination will allow for passive transfer monitoring program development. Immediate refractometry serum total protein concentration determination is beneficial in making timely management and treatment decisions. Serum γ-globulin concentration determination can be used as a confirmatory test.

Abstract

Objective—To evaluate the effect of passive transfer status, determined by measuring serum IgG concentration 24 hours after parturition, on preweaning growth performance in dairy lambs.

Design—Prospective observational study.

Animals—20 healthy Sardinian dairy lambs.

Procedures—Serum IgG concentration was meaured 24 hours after birth. Body weight was measured at birth and at the time of weaning 28 days (ie, 27 to 29 days) after birth. Mean daily gain from birth to day 28 and day 28 weight were used as measures of preweaning growth performance. Regression analysis was used to evaluate associations between serum IgG concentration 24 hours after birth and measures of preweaning growth performance.

Results—Mean ± SD serum IgG concentration 24 hours after birth was 24.6 ± 17.5 mg/mL. Mean body weights at birth and weaning were 2,696 ± 937 g and 9,253 ± 2,116 g, respectively, and mean daily gain was 234 ± 63 g/d. No significant association was detected between serum IgG concentration 24 hours after birth and birth weight. However, serum IgG concentration 24 hours after birth was significantly associated with mean daily gain (R ² = 0.25). Each 1 mg/mL increase in serum IgG concentration 24 hours after birth was associated with a 1.8 g/d increase in mean daily gain and a 60.8-g increase in day 28 weight.

Conclusions and Clinical Relevance—Results indicated that passive transfer status, determined as serum IgG concentration 24 hours after birth, was a significant source of variation in preweaning growth performance in dairy lambs.

Abstract

Objective—To evaluate the effect of passive transfer status (determined from measurements of serum IgG concentration at 24 hours after parturition [sIgG-24]) on preweaning growth performance in dairy goat kids.

Design—Prospective observational study.

Animals—20 healthy nursing dairy doe kids in a natural nonintensive breeding environment.

Procedures—For each kid, sIgG-24 was measured. Body weight was measured at birth and at the time of weaning 30 days (ie, 29 to 31 days) after birth; average daily gain from birth to day 30 and weight at day 30 were used as measures of preweaning growth performance. Regression analysis was used to evaluate associations between sIgG-24 and measures of preweaning growth performance.

Results—Mean ± SD sIgG-24 was 31.7 ± 10.3 mg/mL. Mean body weights at birth and weaning were 4.105 ± 0.981 kg (9.031 ± 2.158 lb) and 9.310 ± 2.554 kg (20.482 ± 5.619 lb), respectively; average daily gain was 0.174 ± 0.072 kg/d (0.383 ± 0.158 lb/d). No significant association was detected between sIgG-24 and birth weight. However, sIgG-24 was significantly associated with average daily gain (R ² = 0.48) and weight at day 30 (R ² = 0.56). Each increase in sIgG-24 of 1 mg/mL was associated with an increase in average daily gain of 0.005 kg/d (0.011 lb/d) and an increase in weight at day 30 of 0.185 kg (0.407 lb).

Conclusions and Clinical Relevance—Results indicated that passive transfer status (determined as sIgG-24) was a significant source of variation in preweaning growth performance in dairy doe kids reared in this nonintensive breeding environment.

Abstract

Objective—To determine the associations between serum IgG concentration and serum activities of γ-glutamyltransferase (GGT), alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and pseudocholinesterase for the potential use of these serum enzymes as predictors of passive transfer status in neonatal lambs.

Design—Prospective observational study.

Animals—47 Sardinian lambs from birth to 2 days old.

Procedure—Serum enzyme activities were measured by use of commercially available kits and a clinical biochemical analyzer. Serum IgG concentration was determined by single radial immunodiffusion. Associations between serum IgG concentration and the activity of each serum enzyme were established by use of regression analysis.

Results—A significant correlation was detected between serum IgG concentration and serum GGT activity in 1- and 2-day-old lambs. Minimal correlations were detected between serum IgG concentration and serum alkaline phosphatase activity in 1-dayold lambs and serum pseudocholinesterase activity in 1- and 2-day-old lambs. No significant associations were detected between serum IgG concentration and serum activities of aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase. A multiple linear regression model was accurate for the estimation of the natural logarithm of serum IgG concentration as a function of the natural logarithm of serum GGT activity and of the age of lambs at the time of sampling (adjusted R ² = 0.89). This model was then used to calculate the serum GGT activity equivalent to various serum IgG concentrations for 1- and 2-day-old lambs.

Conclusions and Clinical Relevance—Results suggested that passive transfer status in neonatal lambs can be successfully predicted by measurement of serum GGT activity but not by measurement of the other enzymes tested. (J Am Vet Med Assoc 2005; 226:951–955)