Milk and Serum J5-Specific Antibody Responses, Milk Production Change, and Clinical Effects following Intramammary Escherichia coli Challenge for J5 Vaccinate and Control Cows

Abstract

Holstein dairy cows (four J5 vaccinates and four controls) selected for no recorded intramammary disease and low somatic cell count (SCC) during the previous lactation were challenged by intramammary infusion of Escherichia coli. Vaccination with J5 was at 8 weeks and again 4 weeks before the anticipated calving date. Cows were challenged at 8 to 16 days in milk (DIM). Shedding of E. coli in milk was significantly higher among controls than vaccinates (no shedding) from 6 h to 21 h postchallenge. From 21 h to 132 h postchallenge, SCC in challenged quarters of controls (5,429,000/ml) was significantly higher than that of vaccinates (490,000/ml). On the day after challenge, milk production in control cows was 8 kg less, while vaccinates gained 0.5 kg, a significant difference. In serum immediately prior to challenge, J5-specific immunoglobulin G1 (IgG1) was significantly higher, IgG2 was nearly significantly higher, and IgM was the same in J5 vaccinates relative to controls. Vaccinates had proportionally more IgG2 in serum postcalving and in the first 12 h following challenge and less IgG2 in milk 24 h after challenge than the controls, approaching statistical significance. The ratio of J5-specific IgG1 and IgG2 combined compared to IgM was significantly higher in vaccinates than in controls in prechallenge serum (ratios of 15.8 and 3.2, respectively) and milk (5.0 and 1.3, respectively). Cows with higher IgM titers in milk 12 h postchallenge produced significantly less milk. Vaccination with J5 was significantly associated with higher production of J5-specific IgG1 and IgG2 in early lactation, reduced SCC, faster clearance of E. coli from milk, and less milk production loss following intramammary challenge.Bovine coliform mastitis is most commonly caused by Escherichia coli and Klebsiella spp. (16,21,30,32). Coliform mastitis can cause abnormal milk, milk production loss, treatment costs, and death of cattle (20,21,30).Vaccination against coliform mastitis with J5 bacterins has been used in the dairy industry for more than 15 years (10, 15). However, the effects of J5 immunization on the bovine mammary immune response have not yet been fully explained (3,12). It is not clear whether J5 vaccination results in J5 E. coli-specific immunoglobulin M (IgM), IgG1, or IgG2 antibody production or in changes in their relative proportions produced in milk or serum or whether such changes are associated with resistance to coliform mastitis (1,5,17,19,28,32). It is generally accepted that either IgM, IgG2, or both isotypes are particularly important in opsonization of bacteria for polymorphonuclear leukocyte (PMN) phagocytosis, and increases in these antibodies against the target mastitis pathogens are desired goals of vaccination against mastitis (1, 5).The primary objectives were to evaluate a commercial J5 vaccine for protection against E. coli challenge and to statistically test for associations between J5 vaccination, outcome measures of clinical mastitis (CM) severity, and J5-specific IgG1, IgG2, and IgM antibodies in m...

Association ofEscherichia coliJ5-Specific Serum Antibody Responses with Clinical Mastitis Outcome for J5 Vaccinate and Control Dairy Cattle

“…J5-specific antibodies (immunoglobulin M [IgM], IgG1, IgG2, and the ratio of IgG1 to IgG2) were therefore compared among vaccinates and controls, as were the relationships of antibody to etiologic pathogen, milk production loss, clinical severity, and time until culling or death. These relationships were deemed important because of their practical relevance and were based upon results of previous intramammary E. coli challenge trials (15,25).…”

Utilização da vacina Escherichia coli J5 na imunização de vacas leiteiras contra mastites causadas por E. coli

“…2003. O pico de contagem bacteriana e a intensidade dos sinais clínicos da doença são dependentes da rapidez e eficiência da resposta dos neutrófilos e da opsonização de bactérias pelos anticorpos (IgG e IgM), facilitando, assim, o reconhecimento destas para a fagocitose e, conseqüentemente, morte intracelular (Hogan et al 1995, Tomita et al 2000, Hogan & Smith 2003, Burvenich et al 2007, Wilson et al 2007). Assim, observa-se uma redução no número de bactérias no interior da glândula mamária, com subsequente redução na intensidade dos casos clínicos.…”

“…Outro fator que corrobora a hipótese aqui apresentada são os achados de Shafer-Weaver et al (1999) e Wilson et al (2007), os quais demonstraram que os títulos séricos de IgG 1 e IgG 2 contra E. coli J5 são significativamente maiores em vacas vacinadas, comparadas as não vacinadas. Este fato, em especial o aumento dos títulos de IgG 2 , favorece a formação da resposta imunológica do tipo 1, importante contra a mastite bovina, principalmente no início da infecção, uma vez que esta imunoglobulina auxilia na fagocitose da bactéria pelo neutrófilo pela rápida fixação do complemento (Burton & Erskine 2003).…”

“…Além disso, 30 horas após o desafio, as vacas vacinadas apresentaram redução na CCS para 300.000 células/mL, enquanto as controle apresentaram média de 2.000.000 células/mL. Esta redução na CCS é um importante indicador da menor reação inflamatória na glândula mamária de vacas vacinadas, demonstrando menor intensidade dos sinais clínicos associada aos efeitos da imunização com E. coli J5 (Wilson et al 2007). Com relação à produção de leite, observou-se que as não vacinadas (J5Vcont) apresentaram média de produção de leite inferior (p<0,05) às vacas do grupo vacinado (J5V) nos primeiros 100 dias de lactação (Quadro 5).…”

“…Os resultados aqui apresentados, em conjunto com os achados de Wilson et al (2007Wilson et al ( , 2008, indicam que a imunização com E. coli J5 está relacionada ao retorno mais rá-pido da produção de leite após o caso clínico, uma vez que ocorre redução na intensidade dos sinais clínicos, permitindo o restabelecimento das funções de produção da glân-dula mamária, com menores efeitos deletérios na produção de leite durante a lactação.…”