The changes in serum total protein and immunoglobulin levels, and BVD, IBR and PI-3 viral neutralizing antibody titers in colostrum-conferred Korean native calves during the first 12 weeks postpartum were studied. The mean concentration of total protein, total immunoglobulin, IgG, IgM and IgA in sera of 9 calves at birth were 3.8 +- 0.5g/dl, 0.27 +- 0.15mg/ml, 0.06 +- 0.08mg/ml, 0.21 +- 0.11mg/ml, and extremely low concentration, respectively. Serum total protein level reached a maximum at 20 hours after birth, total immunoglobulin, IgG and IgM levels at 24 hours, and IgA level at 28 hours, respectively. Serum IgA level reached a minimum at 4 weeks old, IgM level at 5 weeks, total immunoglobulin level at 8 weeks, and IgG level at 10 weeks, respectively. After then those levels had begun to increase, but total protein level was still decreasing at 12 weeks old. The half-lives of IgG, IgM, and IgA were 21.1 days, 4.0 days, and 2.6 days respectively. In 10 Korean native cows immediately after parturition, serum neutralizing antibody titers specific to BVD, IBR and PI-3 virus were 8.7 +- 1.5 log2, 5.7 +-1.2 log2, and 6.8 +- 1.0 log2, respectively. And colostral neutralizing antibody titers against BVD, IBR, and PI-3 virus were 10.1 +- 1.4 log2, 6.8 +- 1.3 log2, and 7.8 +- 1.7 log2, respectively. Before suckling the colostrum, SN antibody titers against BVD, IBR, and PI-3 virus were undetectable from all of 9 Korean native calves. Nevertheless SN antibody titer against BVD virus reached a maximum level (9.2 +- 0.6 log2) at 24 hours after birth, that against IBR virus (6.1 +- 1.0 log2) at 20 hours after birth, and that against PI-3 virus (6.8 +- 0.9 log2) at 32 hours after birth, respectively. In 12 weeks old calves, the SN antibodies against BVD and IBR virus were still decreasing, but that against PI-3 virus reached a minimum at 10 weeks, and increased after 12 weeks of age. The half-lives of SN antibodies against BVD, PI-3 and IBR, virus were 16.0 days, 22.6 days, and 25.5 days, respectively.

A porcine rotavirus isolate was titrated in neonatal colostrum-fed and colostrum-deprived pigs. The stock rotavirus suspension had a titer of 10 /ml and was in its fifteenth cell culture passage in MA-104 cells. Fourteen colostrum-fed pigs were orally inoculated with dilutions of the stock virus suspension ranging from undiluted to 10-5. These pigs did not develop notable clinical signs during the 7-day experimental trial and no pathologic changes were found in intestine, liver, lung, kidney, spleen, or brain. However, rotavirus was detected in feces of the colostrum-fed pigs, using virus isolation and electron microscopic techniques. Rotavirus was also isolated from lung, brain, or spleen of 4 of 12 of these pigs. Sixteen colostrum-deprived pigs were orally inoculated with dilutions of the stock virus suspension ranging from 10-1 to 10-8. Diarrhea developed in 10 of 12 pigs that were given up to the 10-6 dilution. Seven of these 12 pigs died because of the severity of diarrhea. Pigs that died of rotavirus-induced diarrhea had severe villus loss in the jejunum and ileum. Villi of the small intestine of colostrum-deprived pigs that survived the severe diarrhea were within normal limits at the end of the 7-day trial. The colostrum-deprived pigs that were inoculated with a dilution less than 10-6 and survived past 96 hours underwent seroconversion. Rotavirus was detected by virus isolation and electron microscopy in the feces of all colostrum-deprived pigs that survived beyond 18.5 hours after inoculation. Virus was isolated from lungs, brain, or spleen of 12 of 16 colostrum-deprived pigs.

Ontogeny of the third component of complement (C3) was monitored in 10 neonatal swine, using a radial immunodiffusion technique. Significant differences in mean serum C3 concentrations, expressed as percentage of C3 concentration in a pooled standard drawn from 15 adult swine, were not observed between serum samples collected before pigs suckled and at 2 days of age (P = 0.2583). Serum C3 concentrations increased significantly between 2 and 7 days of age (P less than 0.0001) and 7 and 14 days of age (P less than 0.0001). Concentrations comparable with those in adults were not observed at 14 days of age and significant changes were not observed thereafter. Acquisition of adult concentrations of C3 appeared to be a function of endogenous production by the neonate, rather than by passive colostral transfer.

The uptake of colostral IgG and IgM, their serum half-lives, and the rates of endogenous synthesis of IgG and IgM were evaluated in 6 newborn foals fed bovine colostrum (principals) and 6 foals allowed to suckle their dams (controls). The principal foals were fed 400 ml of bovine colostrum (IgG, 10,000 mg/dl and IgM, 200 mg/dl) at 2-hour intervals, from 2 to 20 hours after foaling (total dose, 4 L). Serum IgG and IgM concentrations were determined by single radial immunodiffusion from birth to 98 days of age. At foaling, principal foals had no detectable serum equine IgG, but 1 control foal had serum equine IgG of 185 mg/dl. AFter ingestion of colostrum, there was no significant difference in the maximal serum bovine IgG concentration (range, 1,350 to 3,300 mg/dl) in the principal foals, and maximal serum equine IgG concentration (range, 500 to 6,000 mg/dl). The calculated biological bovine and equine IgG half-life in the principal and control groups was 9.4 and 26 days, respectively. Endogenous IgG synthesis was first detected in 1 principal foal at 3 days of age, but was detected first between 28 and 42 days in the other principal foals. Starting on day 56 there was no significant difference in serum equine IgG concentration between groups. At foaling, foals in both groups had low equine IgM concentrations. In the control foals, there was marked individual variation in the increases in equine IgM concentration (range, 5 to 73 mg/dl) after ingestion of colostrum. With the exception of day 49 after foaling, there was no statistical difference between groups for serum IgM concentration after day 3, and both groups had parallel rates of IgM synthesis. Bovine IgM was undetectable at foaling and maximal serum concentration ranged from 200 to 350 mg/dl following ingestion of colostrum. The calculated bovine and equine IgM half-lives were 8 and 5 days, respectively. The coefficients of absorption of bovine IgG and IgM were 30.9 and 84, respectively, in the principal foals. In the control foals, the coefficient of absorption of equine IgG and IgM was 35 and 30, respectively. One principal foal was excluded from the study because it died of aspiration pneumonia at 2 days of age.

Colostral volume and IgG and IgM concentrations were determined in 6 multiparous mares at foaling and then every 2 hours from 16 to 20 hours after parturition. Serum IgG and IgM concentrations at foaling also were determined in each mare. The rate of mammary secretion was 292 +/- 26 ml/h (range, 202 to 389 ml/h), and the colostral volume was 5.1 +/- 0.5 L (range, 3.2 to 7.0 L). The colostral IgG and IgM contents were 440 +/- 106 g (range, 199 to 855 g) and 3.1 +/- 0.9 g (range, 0.7 g to 7.1 g), respectively. There was no significant correlation between serum and initial colostral IgG and IgM concentration or between serum and total colostral IgG or IgM values. The colostral IgG and IgM concentrations at foaling correlated well with the total colostral IgG and IgM contents, respectively. The initial 250 ml of colostrum contained 10 +/- 1.4% (range, 6.0 to 13.9%) and 6 +/- 1.0% (range, 2.4 to 8.5%) of the total IgG and IgM contents, respectively, and the initial 500 ml of colostrum contained 20 +/- 2.7% (range 12.0 to 27.1%) and 14 +/- 1.2% (8.2 to 17%) of the total colostral IgG and IgM contents, respectively.

We studied the antibody responses to transmissible gastroenteritis (TGE) in serum, colostrum, and milk from sows vaccinated with 2 attenuated (1 IM and 1 oral-IM) and 1 nonattenuated live vaccines and the relationship of these responses with the survivability of the sow's suckling pigs after challenge exposure with virulent TGE virus. Contrary to previous studies, the anti-TGE virus-neutralizing geometric mean titers (GMT) in the milk of sows vaccinated with attenuated vaccines at 3 and 5 days of lactation were similar to that found in the colostrum. Colostral and serum antibody titers were highest in sows given 2 injections of the IM attenuated vaccine. Half of the sows given the oral-IM attenuated vaccine did not seroconvert after 2 oral doses. Only sows vaccinated with the nonattenuated live vaccine had milk GMT that remained high for 21 days after farrowing. The linear relationship between colostral GMT and percentage of survivability of suckling pigs challenge exposed at 3 days of age was significant (P less than 0.05), although the relationship between serum GMT and percentage of survivability and the relationship between milk GMT and percentage of survivability were not significant (P greater than 0.10). The linear relationship between colostral (P less than 0.10) or pre-challenge exposure milk (P less than 0.05) GMT and percentage of survivability of suckling pigs challenge exposed at 5 days of age was significant. We have no adequate explanation for the relatively low colostral GMT, the relatively high milk GMT at 3 and 5 days of lactation in vaccinated sows, or the lack of significant linear relationship between milk GMT and survivability of pigs challenge exposed at 3 days of age.

Serum complement activity and selected hematologic variables were evaluated in 5 newborn foals fed bovine colostrum (principal group) and 6 foals allowed to nurse their dam (control group). Also, bovine colostrum was evaluated for anti-equine antibodies. Precolostral serum hemolytic and conglutinating complement activities were low and increased similarly in foals of both groups to reach adult values between 1 and 3 weeks after birth. Bovine colostrum strongly agglutinated, but did not hemolyse principal foals' RBC and blood containing all known equine blood group alloantigens. Hemolysis was not detected after administration of bovine colostrum. Physiologic anemia developed in foals of principal and control groups during the first week of life. Erythrocyte osmotic fragility in foals of the principal group prior to and after the ingestion of colostrum remained unchanged. However, at 36 hours after birth, there was a significant decrease in erythrocyte osmotic fragility in foals fed homologous colostrum.

The levels of the serum and colostral total protein and immunoglobulins of the Korean native cows immediately after parturition and colostrum-conferred passive immune status of the Korean native calves were studied, and the results obtained were summarized as follows: The mean total protein, total immunoglobulin, IgG, IgM, and IgA concentrations in sera of 10 Korean native cows immediately after parturition were 6.8 +- 0.4g/dl, 24.39 +- 3.41mg/ml, 19.49 +- 2.70 mg/ml, 4.56 +- 1.14mg/ml, and 0.35 +-0.08 mg/ml respectively. And the mean total protein, total immunoglobulin, IgG, IgM, and IgA concentrations in colostrum were 15.0 +- 1.1 g/dl, 116.13 +- 23.07mg/ml, 101.51 +- 22.59mg/ml, 9.46 +- 1.99mg/ml, and 5.17 +- 1.59mg/ml respectively. The mean concentrations of total protein and immunoglobulins in colostrum were 2.1 times to 14.8 times higher than those in serum. The mean concentrations of total protein, total immunoglobulins in colostrum were 2.1 times to 14.8 times higher than those in serum. The mean concentrations of total protein, total immunoglobulin, IgG, IgM and IgA in sera from 211 Korean native calves at 2 days old were 6.7 +- 0.9g/dl, 35.74 +- 9.56mg/ml, 29.06 +-8.07mg/ml, 4.91+-2.99mg/ml, and 1.9 +- 0.99mg.ml respectively. Although the calves had been suckled the dam's colostrum, each of calves was considerably various in levels of serum total protein and immunoglobulins and 16.1 percent of the calves were in a state of hypoglobulinemia

The effects of the serum total protein and immunoglobulin levels of the colostrum-conferred Korean native calves at 2 days of age on the disease incidence during the suckling period were studied. Serum total protein, total immunoglobulin, IgG, and IgM levels of 6 Korean native calves died from septicemia were lower than those of calves survived (p0.05). Korean native calves having low serum total protein and immunoglobulins were affected with diarrhea earlier in life, when compared with calves having high serum levels (P0.05). Korea native calves having low serum total protein were affected with bronchopneumonia earlier in life, when compared with calves having high serum levels (P0.05). Korean native calves having low serum neutralizing antibody titers to bovine viral diarrhea virus had high incidence rate of BVD, when compared with calves having having high serum neutralizing antibody titers (P0.05)