Colostral transfer of gamma glutamyl transpeptidase in calves

Serum gamma glutamyl transpeptidase (GGT) levels in blood samples taken from normal calves which bad suckled colostrum were much higher than those found in healthy adult cattle. Levels of over 60 times the normal adult level were observed. These high levels of GGT took approximately 5 weeks to decline to adult values. Calves which appeared to have not received or absorbed colostrum had GGT levels which would be considered normal in adult cattle. A calf with serum gamma globulin levels which indicated an intermediate amount of colostrum absorption had a level of GGT which was intermediate between that expected for normal adult cattle and that found in calves which had more fully absorbed colostrum. The mean GGT level observed in colostrum from 6 newly-calved cows was over 800 times the mean serum GGT level of the same 6 cows. It therefore appears most likely that GGT is concurrently absorbed with colostrum by calves and this gives rise to the very high levels seen in normal calves.

Calves with very high levels of serum GGT also had raised levels of alkaline phosphatase (AP) which slowly declined but never reached normal adult levels within the 53-day period of observation.

It therefore appears that high levels of both GGT and AP are achieved by calves at the time of colostrum absorption and it is concluded that clinical interpretation of serum GGT and AP levels in young calves is closely dependent upon parallel knowledge of their serum gamma globulin levels.     

Colostral transfer of gamma glutamyl transferase in lambs

Serum gamma glutamyl transferase (GGT) levels in blood samples taken from normal lambs which had suckled colostrum were found to be up to 140 times normal adult levels. These high serum levels declined rapidly reaching a stable level approximately 60% higher than normal adult values by 24 days of age. Newborn lambs which had not yet consumed colostrum had GGT levels which would be considered normal in adult sheep. The GGT concentration in ewes' colostrum was up to 470 times normal serum levels. There was a significant positive correlation between serum GGT and gamma globulin levels in blood samples taken from lambs within 24 hours of birth. Lambs' serum alkaline phosphatase (AP) and serum glutamate oxaloacetate transaminase (SGOT) levels also rose concurrently with the absorption of colostral gamma globulin, with the day 1 AP values being significantly correlated with the serum gamma globulin levels. Serum AP levels declined gradually but were still well above normal adult levels at 45 days of age while SGOT levels returned to normal adult levels by two to three days after birth. It is concluded therefore that, as previously shown in calves, lambs acquire high levels of serum GGT activity from their mothers' colostrum in proportion to the amount of gamma globulin absorbed and also show a concurrent rise in serum AP activity. However the rise in SGOT levels at this time has not been observed in calves.     

Colostral transfer of gamma glutamyl transferase in lambs

Serum gamma glutamyl transferase (GGT) levels in blood samples taken from normal lambs which had suckled colostrum were found to be up to 140 times normal adult levels. These high serum levels declined rapidly reaching a stable level approximately 60% higher than normal adult values by 24 days of age. Newborn lambs which had not yet consumed colostrum had GGT levels which would be considered normal in adult sheep. The GGT concentration in ewes' colostrum was up to 470 times normal serum levels. There was a significant positive correlation between serum GGT and gamma globulin levels in blood samples taken from lambs within 24 hours of birth.

Lambs' serum alkaline phosphatase (AP) and serum glutamate oxaloacetate transaminase (SGOT) levels also rose concurrently with the absorption of colostral gamma globulin, with the day 1 AP values being significantly correlated with the serum gamma globulin levels. Serum AP levels declined gradually but were still well above normal adult levels at 45 days of age while SGOT levels returned to normal adult levels by two to three days after birth.

It is concluded therefore that, as previously shown in calves, lambs acquire high levels of serum GGT activity from their mothers' colostrum in proportion to the amount of gamma globulin absorbed and also show a concurrent rise in serum AP activity. However the rise in SGOT levels at this time has not been observed in calves.     

Relationships between acid-base balance, serum composition and colostrum absorption in newborn calves

Twenty-seven newborn Holstein bull calves were bottle-fed 2 litres of pooled colostrum which had been stored at -20 degrees C. Blood gas analysis before feeding showed a partially compensated respiratory acidosis in most of the calves, although they all appeared to be clinically normal. Mean venous blood pH was 7.346, carbon dioxide tension (PCO2) was 57.5 mmHg (7.6 kPa), bicarbonate was 30.6 mmol/l and base excess was 3.82 mmol/l. Mean serum IgG1 increased to 8.1 g/l after feeding colostrum. Several significant positive correlations were observed between post-absorptive serum protein, IgG1, IgM, gamma-glutamyltransferase (gamma GT) and D-xylose. Calves with either low serum albumin, high serum CK or low serum gamma GT before feeding tended to have less absorption of colostral protein. It was concluded that reduced absorption of IgG1 from colostrum is associated with hypercapnia in apparently healthy newborn calves.     

Colostrum intake by dairy calves

AIMS: To determine which clinical parameters could be used to identify calves with low serum immunoglobulin levels and to examine the influence of cow and calf behaviour on colostrum intake. METHODS: Blood samples were taken from 74 dairy calves after they were separated from their dams, and analysed for serum gamma glutamyltransferase (GGT) activity. Physical and behavioural measurements were taken for 57 of these calves at this time. The behaviour of 2 1 dairy cows and their calves was observed between birth and the time the calves were separated when a blood sample was taken from 17 of them and analysed for GGT. RESULTS: Low serum GGT activities (below 200 U/l GGT), indicating low serum immunoglobulin levels, were found in 45% of the group of 74 calves. The calves which had not received colostrum were not easy to distinguish from those that had on the basis of physical or behavioural features. The amount of time that the 2 1 calves spent with their dams before being separated ranged from 1.2 to 24.9 hours. Thirty-three per cent of these calves had not sucked within this time. Of the calves that did suck, 79% did so within 6 hours of birth. CONCLUSIONS: About one half of New Zealand dairy calves may not receive colostrum from their dams even when they are together for up to 24 hours. Most calves that are going to suck of their own accord will do so within 6 hours of birth. CLINICAL SIGNIFICANCE: Dairy calves should be removed from their dams after 6 hours and fed colostrum to guarantee that they receive sufficient immunoglobulins.     

Passive protection of calves against experimental infection with Salmonella typhimurium

Cows were vaccinated with formalin-killed Salmonella typhimurium approximately seven weeks and two weeks before parturition to investigate whether passive immunity could protect their calves against experimental S typhimurium infection. After birth the calves were left with their dam for 48 hours and then separated and fed cold, stored colostrum from their own dam for a further eight days. Oral challenge five days after birth with 10(8) S typhimurium did not result in the death of these calves even when they had absorbed little colostrum. Mortality was reduced to 22 per cent in calves which sucked from vaccinated dams and were then fed colostrum from unvaccinated cows and to 50 per cent in calves born to unvaccinated cows and later fed colostrum from vaccinated animals. Calves which sucked from a vaccinated dam and then received stored colostrum from the same cow excreted salmonellas for significantly shorter periods after challenge and were less often infected at necropsy 28 days after inoculation. Protection was not correlated with the levels of O or H agglutinating antibodies in serum, which were at a maximum 24 hours after sucking and then slowly declined. There was no evidence of an active antibody response in the serum. Measurement of the O and H response of cows after vaccination indicated that the vaccination schedule could be improved. The highest levels of agglutinating antibody were measured between two and three weeks after the first vaccination and there was only a minimal response to the second vaccination before parturition.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of enhancing curd formation during the first colostrum feed on absorption of gamma glutamyl transferase by newborn calves

OBJECTIVE: To examine the effects of curd formation within the abomasum, on the absorption of gamma glutamyl transferase (GGT) from colostrum in newborn calves. DESIGN: An in vivo physiological study with controls, and in vitro examination of calf abomasal fluid. PROCEDURES: Newborn calves were taken from cows without allowing them to suckle. They were fed either 1.5 kg colostrum or 1.5 kg colostrum plus rennet, with intervals between calving and colostrum feeding ranging from 0.4 to 12.7 h. Absorption of proteins from the whey component of colostrum was assessed from the rise in activity of serum GGT. In in vitro studies, colostrum was incubated with bovine amniotic fluid, newborn calf abomasal fluid or newborn calf forestomach contents, with or without rennet, to test the curd inhibiting effects of components in the abomasal fluid of newborn calves. RESULTS: In vivo: addition of rennet to the colostrum feed reduced the proportion of calves with serum GGT activity below 500 U/L by 60%. In vitro: 43% of newborn calves lacked curd forming activity in their abomasal fluid, and that deficiency was corrected by adding rennet to the incubation medium. CONCLUSIONS: Some calves are born with low amounts of curd forming enzyme activity in the abomasum. This may compromise their ability to absorb large whey proteins from the first feed of colostrum. Adding rennet to the first colostrum feed may improve passive immunity in those calves.     

Exploring passive transfer in muskoxen (Ovibos moschatus).

Poor calf production and ill thrift in 3-4 mo olds are common limiting problems in raising and maintaining captive muskoxen (Ovibos moschatus). Acute onset of a rapidly progressing enteritis and septicemia in neonatal calves (2-7 days of age) caused by Escherichia coli not normally considered pathogenic in domestic animals is a serious problem in many captive muskoxen facilities. Serum immunoglobulin G (IgG) levels, total protein, albumin, and globulin levels in captive periparturient muskox females and their neonatal calves were compared with levels found in other species in which these parameters have been well described. Results showed that all females in the study had IgG present in their serum (mean = 1,232.14 mg/dl, SD = 178.34 mg/dl, as measured via radial immunodiffusion). Calves were probably born agammaglobulinemic or hypogammaglobulinemic. IgG levels quickly rose in calves after initial colostrum intake to levels similar to those seen in other domestic ruminants. Our results suggest that passive transfer of immunity in muskoxen is similar to what is reported in domestic livestock and that reference ranges from domestic cattle may be used to assist interpretation of serum IgG levels in muskoxen. In addition, the positive relationship between serum protein and globulin levels with serum IgG levels is similar to that reported for Holstein cattle and thus provides a useful indicator of passive transfer in muskoxen.     

The specificity of antibody responses in cattle naturally exposed to Fasciola hepatica

Fasciola hepatica causes significant morbidity and mortality in dairy cattle in the Andean region of Cajamarca, Peru, where prevalence of infection of up to 78% has been reported. ELISA and Western blot analyses were used to characterise antibody responses in dairy cattle to adult F. hepatica to excretory-secretory (E/S), somatic (SO) and surface (SU) antigens. Three groups of dairy cattle - calves, heifers and adult cows - naturally exposed to F. hepatica in this region, were monitored every 2 months over a 2-year period. Calves, heifers and adult cows all had antibodies which recognised a 28kDa protein in the SO preparation, whereas only adult cows had antibodies that recognised a 28kDa protein in E/S products. All three groups of cattle responded to a 60-66kDa group of proteins in E/S and SU preparations and a 17kDa antigen in SO products was recognised by antibodies from cows and heifers but not calves. The total antibody response to E/S antigens measured by ELISA, increased over time in calves and remained constantly high over the 2-year period in all three groups of cattle. Slight fluctuations in the antibody response occurred in the group of heifers and cows coinciding with seasonal changes in the level of challenge.     

安格斯母牛初乳产量与质量测定及其新生犊牛被动免疫效果评价

【目的】 新生犊牛被动免疫转移失败（failure of passive transfer,FPT）会导致犊牛发病率和死亡率显著增高,影响后期生长发育。本试验针对国外引进的安格斯母牛初乳产量和质量进行测定,并对其新生犊牛被动免疫效果进行评估,以期为新生犊牛初乳管理措施制定提供科学依据。【方法】 随机选择健康安格斯初产母牛（24月龄）和经产母牛（36~48月龄）各15头,待母牛产犊后立即进行人工挤奶测定初乳产量、营养成分及免疫球蛋白浓度。选取初产和经产新生犊牛各15头,测定其初生重,分别采集犊牛出生后未食初乳（0 h）和食初乳后（24~36 h）血样,测定其血清总蛋白含量及各生理生化指标。【结果】 初产母牛平均初乳产量极显著低于经产母牛,但其初乳中乳蛋白、非脂乳固体、乳糖、灰分含量,以及密度和电导率均极显著高于经产母牛（P<0.01）。初产母牛和经产母牛初乳中免疫球蛋白浓度分别为28.72%和26.24%,合格率分别为93.33%和91.67%,差异均不显著（P>0.05）;初产和经产新生犊牛被动免疫失败率分别为33.3%和25.0%;初产新生犊牛平均初生重极显著低于经产新生犊牛（P<0.01）;被动免疫成功犊牛平均初生重和球蛋白含量均极显著高于被动免疫失败犊牛（P<0.01）。【结论】 新疆安格斯犊牛FPT的主要原因可能是母牛初乳产量低导致新生犊牛初乳摄入不足,初生重较低的犊牛FPT的风险性较高。本研究为制定切实可行的新生安格斯犊牛初乳补饲计划提供了科学基础。     

An epidemiological study of gammaglobulin levels in newborn calves

The effect of various factors on serum gammaglobulin concentration in newborn dairy calves was studied in 181 calves on six commercial farms. The refractometer test for monitoring colostrum management was found to be a reliable, rapid and practical method up to 6 days after birth. The three factors, time of first colostrum feeding, quantity of first colostrum intake and gammaglobulin concentration in first colostrum, explained 19.9% of the variation in serum gammaglobulin concentration. Time of milking, time of first colostrum intake and gammaglobulin concentration in first colostrum explained 21.0% of the variation in serum gammaglobulin concentration. Calves from first lactation cows showed lower serum gammaglobulin concentration than calves of older cows.     

The efficacy of colostrum from cows vaccinated with rotavirus in protecting calves to experimentally induced rotavirus infection

Calves which were continuously fed colostrum from vaccinated cows for the first ten days of life, were fully refractory to experimental infection with strain 81/36 F of bovine rotavirus. By contrast, the response to virus exposure of calves which were treated with normal colostrum was identical to that of the control calves, in that they underwent severe diarrhea and a significant slowing of the growth rate. The antibody titer in the milk of vaccinated cows tends to decline rapidly so that it no longer provides any protective effect. Two alternatives were considered feasible in improving prophylaxis for rotavirus infections: (a) the continuous feeding of calves with 1st day colostrum as part of the ration throughout the period of greatest risk (first week of life), or (b) enhancing the efficacy of the vaccine in pregnant cows to the point where antibody concentration in the milk would remain at a protective level.     

Detection of bovine antibodies to the outer membrane of ruminal Bacteroides succinogenes by enzyme-linked immunosorbent assay (ELISA)

The enzyme-linked immunosorbent assay (ELISA) was used to detect bovine serum antibodies directed to the outer membrane antigen of a ruminal bacteria, Bacteroides succinogenes. The outer membrane antigen of B. succinogenes was highly reactive against homologous antiserum, compared with rabbit sera raised against B. ruminicola subsp. ruminicola, B. ruminicola subsp. brevis and Selenomonas ruminantium. The titers of sera from colostrum-deprived calves were negligible level, while those of sera from colostrum-fed calves were relatively high. The mean titer of sera from 10 day-old calves was significantly (p less than 0.01) higher than that of 40 day-old calves, and was significantly (p less than 0.01) lower than that of adult cattle. The mean titer of sera from dairy cows which fed high-roughage diet was higher than that of feedlot cattle which fed high-concentrate diet. These results suggest that the antibodies against the outer membrane antigen of B. succinogenes transfer to calves via the colostrum, and that the titers of cows are affected by the way of feed management.     

Reproducibility of bovine neonatal pancytopenia (BNP) via the application of colostrum

A haemorrhagic diathesis has been observed in young calves since 2007 which is described as bovine neonatal pancytopenia (BNP) and presents a completely new disease. The objectives of our investigation were to test if BNP could be reproduced using colostrum of cows with a BNP history and pre-colostral calves from farms where BNP has not been observed. In the present experiment, 22 German Holstein calves from BNP-free farms were fed four to six hours after birth 2.5 l colostrum from cows which had been reported to have had at least one calf with BNP in the last lactation. We distinguished three different experimental groups according to the composition of the colostrum. In experimental group I, each of the six calves received colostrum of a single cow, in experimental group II all six calves received colostrum from the same cow and in experimental group III each of the ten calves received a colostrum mix from ten different cows. Clinical signs of BNP were observed in 50% of the calves in experimental group I, 67% of the calves in experimental group II and all calves in experimental group III. The lethality in the three experimental groups was significantly different with rates of 16.7%, 66.7% and 80%, respectively. Calves fed with a colostrum-mix in experimental group III had the highest lethality. Neither the farm nor the amount of the colostrum fed had a significant effect on the occurrence and course of BNP. The profiles for thrombocytes, leucocytes and erythrocytes significantly differed in dependence of the severity of BNP signs. Calves with non-lethal BNP showed thrombocytopenia with values below 100 G/l on the 1th to 3rd and the 7th to 11th day of life. In calves with lethal BNP, thrombocytes decreased under 50 G/l from day 5. In calves with non-lethal BNP, a decrease of the leucocytes under the threshold was present only for a short period of time. In calves with lethal BNP, leucocytes decreased in the first 5 days after birth continuously and increased on the 6th to the 8th day to normal values and then a rapid decrease occurred. Erythrocytes decreased under the normal threshold just in the last two days before the calves died or were euthanized. Thus, the present experiments showed that colostrum of cows with a BNP-history and vaccination with PregSure BVD from Pfizer caused lethal BNP. We can assume that the different reactions of the calves are due to immunogenetic reactions to colostral alloreactive antibodies. The reaction spectrum of calves depends on the presence of antigens which can react with these colostral antibodies. The experimental results can explain the different incidences of BNP within and among farms as well as between breeds.     

Comparison of rapid laboratory tests for failure of passive transfer in the bovine

Background

Failure of passive transfer of maternal immunity via colostrum can occur in the bovine, and a number of blood tests have been developed to test calves for this failure. It is not clear which test is most suitable for this purpose. The objective was to examine the most commonly used tests for failure of passive transfer and to decide which is most suitable for routine laboratory use. 126 serum samples were taken from calves of dairy cows after birth but prior to colostrum feeding, and at 48 h of age. Five different tests were compared against radial immunodiffusion which is considered the appropriate reference method. These tests were serum gamma-glutamyltransferase levels, serum protein levels, serum globulin levels, an enzyme linked immunosorbent assay and the zinc sulphate turbidity test.

Results

The tests examined displayed high sensitivity but widely varying specificity. Examination of the use of different cut-off points allowed some improvement in specificity at the expense of sensitivity, but the tests which had performed best at the original cut-off points still displayed the best performance. Gamma-glutamyltransferase levels as a measure of colostrum absorption returned, in this study, the best balance between sensitivity and specificity. The ELISA used in this study and serum globulin levels displayed performance similar to the gamma-glutamyltransferase levels. Serum total protein was less successful than others examined at providing both sensitivity and specificity but may, when performed via refractometer, be useful for on-farm testing. As currently performed the poor sensitivity for which the zinc sulphate turbidity test is most often criticized is evident. Modification of the cut-off point to increase specificity is less successful at balancing these parameters than the ELISA, gamma-glutamyltransferase levels, and globulin levels.

Conclusions

Gamma-glutamyltransferase levels, ELISA testing and circulating globulin levels performed best in detecting failure of passive transfer in serum samples, although all three had some practical considerations.     

The effects of genotype and selected environmental factors on colostrum production and intake in cattle

The aim of this study was to determine effects of genotype and selected environmental factors on colostrum production, intake, and efficiency in the cattle. The investigations were conducted on 67 dam-calf pairs. All cows were of Polish Holstein-Friesian breed, the Black-and-White variety (PHF-HO), whereas calves were sired by bulls of the following breeds: PHF-HO, Polish Holstein-Friesian of the Red-and-White variety (PHF-RW), Jersey (JE), Montbéliarde (MB) and Limousine (LI). The colostrum was collected from cows and offered to calves "from bucket" thrice a day. The amount of produced colostrum considerably exceeded the ability of its consumption by calves. Low share of HF genes in the cow, older cow's age and calving in the period from January to April appeared to be favorable factors for colostrum production. Calves born to cows with low HF gene share drank more colostrum than calves originating from cows with higher gene share of this breed. Crosses with JE drank the highest amount of the colostrum in relation to body weight, while MB-sired calves drank the highest amount in absolute terms. Colostrum intake was positively correlated with the dam's age. Furthermore, it was shown that in case of the first colostrum intake the most favorable period was from May to September, while in cases of total intake in the first day of life and mean intake in the first 5 days of life it was the period from January to April. Crosses with JE were characterized by extremely high use of colostrum per unit of body weight gain.     

Effects of the ingestion of whole colostrum or cell-free colostrum on the capacity of leukocytes in newborn calves to stimulate or respond in one-way mixed leukocyte cultures

OBJECTIVE: To evaluate effects of colostral cells on the ability of neonatal leukocytes to respond in a mixed leukocyte response (MLR) as a means of evaluating specific immune responsiveness. ANIMALS: 10 Holstein calves, their respective dams, and 10 unrelated adult Holstein cows. PROCEDURE: Soon after birth, their calves were fed maternal whole colostrum or colostrum after cells were removed by centrifugation. Responses for leukocytes obtained from calves during the first 5 weeks after birth, their dams, and unrelated cows were measured by use of 1-way MLR as an indicator of immune development. An internal control treatment, proliferation of lymphocytes stimulated with Staphylococcus enterotoxin B (SEB), was also measured. RESULTS: Transfer of colostral leukocytes had a significant effect on the MLR and SEB-induced response in calves. Calves receiving whole colostrum had enhanced responses to maternal and unrelated leukocytes 24 hours after ingestion of colostrum. These responses decreased quickly, indicating direct modulation of the neonatal immune response. Calves receiving whole colostrum effectively stimulated the MLR by 24 hours after ingestion of colostrum. In contrast, calves receiving acellular colostrum did not effectively stimulate the MLR until 2 to 3 weeks after birth. CONCLUSIONS AND CLINICAL RELEVANCE: Ingestion of maternal colostral leukocytes immediately after birth stimulates development of the neonatal immune system. These maternal leukocytes enhance development of antigen-presenting capacity as indicated by their ability to stimulate the MLR and SEB response. The influence of ingested maternal cells on neonatal immunity was also indicated by a reduction in reactivity of neonatal cells to maternal alloantigens.     

Health status and risk factors associated with failure of passive transfer of immunity in newborn beef calves in Québec

Risk factors associated with failure of passive transfer of immunity (FPT) were evaluated among newborn beef calves in Québec. Physical examination was performed on calves born of a normal calving and blood samples were collected for determination of health status and measurement of serum concentration of immunoglobulin (Ig) G1. Of 225 calves, from 45 herds, 19% showed FPT (serum IgG1 concentration < 10.0 g/L). Calves born in a stanchion-stall were more likely to show FPT (OR: 10.2). Calves bottle-fed colostrum were less at risk for FPT (OR: 0.06). Calf gender, month of birth, dam parity, and dam body condition score were not associated with FPT. No association was detected between FPT and health status. Special care should be given to calves born from cows in a stanchion-stall to ensure adequate colostrum intake. Failure of passive transfer of immunity should be considered with other risk factors when investigating morbidity.     

Humoral immune response of water buffalo monitored with three different antigens of Toxocara vitulorum

Humoral immune response of water buffalo naturally infected with Toxocara vitulorum was monitored using three different antigens of this parasite in serum and colostrum of buffalo cows and calves. Soluble extract (Ex) and excretory/secretory (ES) larval antigens and perienteric fluid antigen (Pe) of adult T. vitulorum were used to measure the antibody levels by an indirect ELISA. Serum of 7-12 buffalo cows for the first 365 days and colostrum of the same number of buffalo cows for the first 60 days of parturition, and serum of 8-10 buffalo calves for the first 365 days after birth were assayed. The ELISA detected antibodies against all three T. vitulorum antigens in the colostrum and serum of 100% of buffalo cows and calves examined. The highest antibody levels against Ex, ES and Pe antigens were detected in the buffalo cow sera during the perinatal period and were maintained at high levels through 300 days after parturition. On the other hand, colostrum antibody concentrations of all three antigens were highest on the first day post-parturition, but decreased sharply during the first 15 days. Concomitantly to the monitoring of immune response, the parasitic status of the calves was also evaluated. In calves, antibodies passively acquired were at the highest concentrations 24 h after birth and remained at high levels until 45 days coincidentally with the peak of T. vitulorum infection. The rejection of the worms by the calves occurred simultaneously with the decline of antibody levels, which reached their lowest levels between 76 and 150 days. Thereafter, probably because of the presence of adults/larvae stimulation, the calves acquired active immunity and the antibodies started to increase slightly in the serum and plateaued between the days 211 and 365. All three antigens were detected by the serum antibodies of buffalo calves; however, the concentration of anti-Pe antibody was higher than anti-EX and anti-ES, particularly after 90 days of age. By conclusion, the buffalo cows develop immunity and keep high levels of antibodies against T. vitulorum-Ex, ES and Pe antigens and these antibodies are transferred to their calves through the colostrum. This passively acquired immunity does not protect the calves against the acquisition of the infection, but these antibodies, passively or actively acquired, may have an important role during worm rejection by the calves and prevention of intestinal reinfection.     

The effect of maternally derived immunoglobulin G on the risk of respiratory disease in heifers during the first 3 months of life

The objectives were to investigate the association between postcolostral serum IgG and the development of calf pneumonia, to elaborate the risk factors for pneumonia, and to compare the risk factors for clinician- and caregiver-diagnosed respiratory disease. In a prospective observational cohort study, 410 heifer calves were clinically examined weekly by a veterinarian during their first 3 months of life. With an initial questionnaire and during these weekly visits, management data were collected. A nested matched case-control design was used to compare risk factors between 105 calves with respiratory disease and their 59 control calves from the same initial population. The IgG levels were determined from blood samples taken within 2 weeks after colostrum intake. The appropriate cutoff point for the postcolostral IgG level to indicate failure of passive antibody transfer when predicting pneumonia appeared to be between 800 and 1300 mg/dl (values < or = the cutoff point indicated failure). Calves with low IgG levels had 2-times higher odds of pneumonia than calves with higher IgG concentrations. Housing mostly in the presence of adult cattle was a risk factor for pneumonia, whereas housing mostly alone in a hutch was protective. Feeding of mastitic colostrum was a risk factor for clinician-diagnosed pneumonia in the analysis of the cohort study but not in the matched case-control design. There was a three-times higher risk of pneumonia if calves were given their dam's colostrum for the first feeding and the dam had clinical mastitis at the time of first milking. Caregiver- and clinician-diagnosed pneumonia had slightly different risk factors which implies that caution should be used when comparing studies based on different definitions of pneumonia. The practical implications of this study are that more attention should be paid to proper housing conditions of the calves in order to reduce incidence of pneumonia.