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1.
J Dairy Sci ; 99(6): 4870-4874, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27060821

ABSTRACT

Dairy cattle evaluated for immune responses and identified as high responders are known to have a lower occurrence of economically important diseases, including mastitis, metritis, ketosis, and retained placenta. These high immune responders have also been shown to make more antibody following vaccination and to have improved milk and colostrum quality. Therefore, breeding for improved immune response is expected to have several benefits in the dairy industry. However, a concern of such an approach to improve animal health is the potential cost of lost production due to an allocation of host resources to mount a robust immune response. The objective of this study was to evaluate early- and late-lactation production parameters in cattle classified as having high, average, or low estimated breeding values (EBV) for cell-mediated (CMIR), antibody-mediated (AMIR), and overall immune responses. A total of 561 cows from 6 herds were phenotyped for immune response and ranked based on EBV for CMIR and AMIR. A linear animal model was used to evaluate differences in milk, fat, and protein yields among immune response groups, and a regression analysis was conducted based on immune response EBV. Overall, no difference in production parameters was found based on immune response rank; however, some positive relationships with immune response EBV were found, suggesting that breeding for enhanced immune responsiveness as a prophylactic approach to improve animal health would not come at the cost of lost production.


Subject(s)
Cattle/immunology , Immunity , Lactation , Milk/chemistry , Animals , Breeding , Canada , Colostrum/chemistry , Dietary Fats/analysis , Female , Milk Proteins/analysis , Phenotype , Vaccination/veterinary
2.
J Dairy Sci ; 99(3): 2364-2371, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26723120

ABSTRACT

Genetic selection for enhanced immune response has been shown to decrease disease occurrence in dairy cattle. Cows can be classified as high (H), average, or low responders based on antibody-mediated immune response (AMIR), predominated by type-2 cytokine production, and cell-mediated immune response (CMIR) through estimated breeding values for these traits. The purpose of this study was to identify in vitro tests that correlate with in vivo immune response phenotyping in dairy cattle. Blood mononuclear cells (BMC) isolated from cows classified as H-AMIR and H-CMIR through estimated breeding values for immune response traits were stimulated with concanavalin A (ConA; Sigma Aldrich, St. Louis, MO) and gene expression, cytokine production, and cell proliferation was determined at multiple time points. A repeated measures model, which included the effects of immune response group, parity, and stage of lactation, was used to compare differences between immune response phenotype groups. The H-AMIR cows produced more IL-4 protein than H-CMIR cows at 48 h; however, no difference in gene expression of type-2 transcription factor GATA3 or IL4 was noted. The BMC from H-CMIR cows had increased production of IFN-γ protein at 48, 72, and 96 h compared with H-AMIR animals. Further, H-CMIR cows had increased expression of the IFNG gene at 16, 24, and 48 h post-treatment with ConA, although expression of the type-1 transcription factor gene TBX21 did not differ between immune response groups. Although proliferation of BMC increased from 24 to 72 h after ConA stimulation, no differences were found between the immune response groups. Overall, stimulation of H-AMIR and H-CMIR bovine BMC with ConA resulted in distinct cytokine production profiles according to genetically defined groups. These distinct cytokine profiles could be used to define disease resistance phenotypes in dairy cows according to stimulation in vitro; however, other immune response phenotypes should be assessed.


Subject(s)
Cattle/genetics , Cattle/immunology , Concanavalin A/pharmacology , Immunity, Cellular , Immunity, Innate , Immunologic Tests/veterinary , Mitogens/pharmacology , Animals , Cell Proliferation/drug effects , Cytokines/drug effects , Cytokines/metabolism , Female , Gene Expression/drug effects
3.
J Dairy Sci ; 99(3): 2358-2363, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26774725

ABSTRACT

The objective of this study was to evaluate IgG and ß-lactoglobulin (ß-LG) concentrations in colostrum and milk of Canadian Holsteins (n=108) classified as high (H), average (A), or low (L) for antibody-mediated (AMIR) or cell-mediated immune responses (CMIR) based on estimated breeding values. It was hypothesized that H-AMIR and H-CMIR cows produce colostrum (first milking) and milk (d 5 postcalving) with higher concentrations of IgG and ß-LG. Data for IgG and ß-LG in colostrum and milk were analyzed independently using mixed linear models. Least squares means were compared using Tukey's test. Cows classified as H-AMIR had higher IgG and ß-LG concentrations in colostrum compared with A- and L-AMIR cows; 84% of H-AMIR, 69% of A-AMIR, and 68% of L-AMIR cows had over 5,000 mg/dL IgG in colostrum. No differences in IgG and ß-LG concentrations in colostrum were noted among cows ranked on CMIR or in milk of cows ranked on AMIR. ß-Lactoglobulin and IgG concentrations were positively correlated in colostrum. Breeding cows for H-AMIR status may reduce failure of passive transfer of IgG in their calves; ß-LG may play a role in bovine immune defenses. Colostrum from H-AMIR cows may serve as a more economical feedstock source for manufacturing natural health products.


Subject(s)
Cattle/immunology , Colostrum/chemistry , Immunoglobulin G/metabolism , Lactoglobulins/metabolism , Milk/chemistry , Animals , Cattle/metabolism , Enzyme-Linked Immunosorbent Assay/veterinary , Female , Immunodiffusion/veterinary , Lactation
4.
J Dairy Sci ; 96(6): 3965-72, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23587396

ABSTRACT

The objectives of this study were to evaluate (1) natural antibodies (NAb) in Canadian Holstein cows, (2) genetic parameters and associations between NAb and specific antibody (SpAb), and (3) the association of NAb with clinical mastitis and differences in incidence rates of clinical mastitis (IRCM) among cows classified as high, average, or low responders for NAb. Natural antibodies (IgG and IgM) to keyhole limpet hemocyanin and SpAb to a type 2 test antigen were measured on 451 Holsteins from 41 herds across Canada. A series of uni- and tri-variate linear animal models were used to estimate genetic parameters and breeding values for NAb and SpAb. The models included the fixed effects of parity and stage of lactation and the random effects of herd-technician, animal, and residual. Using estimated breeding values for NAb, cows were classified as high, average, or low responders and phenotypic associations with the IRCM were investigated and a logistic regression performed. The estimated heritability was 0.27 for SpAb, and was 0.32 and 0.18 for NAb of the IgG and IgM isotypes, respectively. No significant genetic correlations were found between SpAb and NAb. Although no significant differences in the IRCM were found when cows were classified based on NAb IgG, cows classified as high responders for NAb IgM tended to have a lower IRCM compared with other cows. Immunoglobulin-M was associated with a decreased risk of clinical mastitis (odds ratio=0.958). Results of this study suggest the potential to use NAb IgM as an additional tool to select for disease resistance in cattle, but results need to be validated with a larger sample size.


Subject(s)
Antibodies/genetics , Mastitis, Bovine/immunology , Animals , Antibodies/immunology , Breeding , Canada , Cattle , Disease Resistance/genetics , Disease Resistance/immunology , Female , Hemocyanins/immunology , Immunoglobulin G/blood , Immunoglobulin G/genetics , Immunoglobulin G/immunology , Immunoglobulin M/blood , Immunoglobulin M/genetics , Immunoglobulin M/immunology , Phenotype
5.
J Dairy Sci ; 95(7): 3888-93, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22720943

ABSTRACT

The objective of this study was to use previously calculated estimated breeding values for cell- (CMIR) and antibody-mediated immune responses (AMIR) to determine associations between immune response (IR) and economically important diseases of dairy cattle. In total, 699 Holsteins were classified as high, average, or low for CMIR, AMIR, and overall IR (combined CMIR and AMIR), and associations with mastitis, metritis, ketosis, displaced abomasums, and retained fetal membranes were determined. The incidence of mastitis was higher among average cows as compared with cows classified as high AMIR [odds ratio (OR)=2.5], high CMIR (OR=1.8), or high IR (OR=1.8). Low-CMIR cows had a higher incidence of metritis (OR=11.3) and low-IR cows had a higher incidence of displaced abomasum (OR=4.1) and retained fetal membrane (OR=2.8) than did average responders. Results of this study show that cows classified as high immune responders have lower occurrence of disease, suggesting that breeding cattle for enhanced IR may be a feasible approach to decrease the incidence of infectious and metabolic diseases in the dairy industry.


Subject(s)
Adaptive Immunity/immunology , Cattle Diseases/immunology , Abomasum , Animals , Cattle , Cattle Diseases/epidemiology , Disease Susceptibility/immunology , Endometritis/epidemiology , Endometritis/immunology , Endometritis/veterinary , Female , Immunity, Cellular/immunology , Immunity, Humoral/immunology , Incidence , Ketosis/epidemiology , Ketosis/immunology , Ketosis/veterinary , Mastitis, Bovine/epidemiology , Mastitis, Bovine/immunology , Placenta, Retained/epidemiology , Placenta, Retained/immunology , Placenta, Retained/veterinary , Pregnancy , Stomach Diseases/epidemiology , Stomach Diseases/immunology , Stomach Diseases/veterinary
6.
J Dairy Sci ; 95(1): 401-9, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22192219

ABSTRACT

The objectives of this study were to estimate genetic parameters of cell-mediated (CMIR) and antibody-mediated (AMIR) immune response (IR) traits of Holstein cattle on a national scale and to associate estimated breeding values of CMIR, AMIR, and overall IR with routinely evaluated traits in Canada. In collaboration with the Canadian Bovine Mastitis Research Network, 445 Holstein cows from 42 herds across Canada were immunized to measure delayed-type hypersensitivity as an indicator of CMIR and serum antibody for AMIR to putative type 1 and type 2 test antigens, respectively. Primary (d 14) and secondary (d 21) AMIR were measured for both IgG1 and IgG2. A series of uni- and bivariate linear animal models were used to estimate genetic parameters and breeding values for CMIR and the 4 AMIR traits. The models included the fixed effects of parity and stage of lactation and the random effects of herd-technician, animal, and residual. Heritability of CMIR was 0.19 (SE=0.10) and for AMIR traits ranged from 0.16 to 0.41 (SE=0.09-0.11) depending on time and antibody isotype. The genetic correlations between CMIR and AMIR were negative and ranged from -0.13 to -0.45 (SE=0.32-0.46). The results indicate adaptive immune response traits are moderately heritable and provide a potential for genetic selection. The negative genetic correlations between CMIR and AMIR indicate the importance of considering both traits in breeding for overall disease resistance. Significant beneficial associations between the reproductive traits number of services and first service to conception were found, which may indicate these reproductive traits would improve with genetic selection for enhanced immune response.


Subject(s)
Adaptive Immunity/genetics , Cattle/genetics , Animals , Canada , Cattle/immunology , Immunity, Humoral/genetics , Models, Genetic , Phenotype , Quantitative Trait, Heritable
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