Field Trials of a Vaccine Against Bovine Mastitis. 1. Evaluation in Heifers

Abstract

A vaccine was developed against bovine mastitis based on inactivated, highly encapsulated Staphylococcus aureus cells; a crude extract of Staph. aureus exopolysaccharides; and inactivated, unencapsulated Staph, aureus and Streptococcus spp. cells. This vaccine was tested on 30 heifers during a 7-mo period. The 30 heifers were randomly assigned to three groups of 10 heifers each. The prepartum group received two injections of the vaccine at 8 and 4 wk before calving, and the postpartum group received two injections at 1 and 5 wk after calving. The control group received two injections of a placebo at 8 and 4 wk before calving. The vaccine or the placebo was administered subcutaneously in the brachiocephalicus muscle of the neck. The frequencies of intramammary infections caused by Staph. aureus were reduced from 18.8% for heifers in the control group to 6.7 and 6.0% for heifers in the prepartum and postpartum groups, respectively. This protective effect was maintained for at least 6 mo. The relative risk of mastitis caused by Staph. aureus was 0.31 and 0.28 for heifers in the prepartum and postpartum groups, respectively, compared with that for heifers in the control group. The results of the trial indicated the effectiveness of the vaccine in decreasing the incidence of intrammammary infections caused by Staph. aureus. A slight but nonsignificant increase occurred in fat production in the milk of vaccinated cows. The vaccine had no observable effect on somatic cell count or streptococcal infections.

Genetic management of infectious diseases: a heterogeneous epidemio-genetic model illustrated with S. aureus mastitis

“…Indeed, culling of chronically infected cows, dry cow therapy and antibiotic treatment are recommended in the control of S. aureus infection [13,22]. This was exemplified with the lower R 0 in controlled (R 0 = 0.71) than uncontrolled (R 0 = 3.74) herds under the genetic Structure 1.…”

Efficacy of an autogenous vaccine against highly virulent <i>Staphylococcus aureus </i>infection in rabbits

“…Those supplements to the bacterin are considered to enhance its efficacy. A vaccine consisting of inactivated, highly encapsulated S. aureus cells, inactivated unencapsulated S. aureus and crude extract of S. aureus exopolysaccharides was tested in heifers and dairy cows in field trials Giraudo et al, 1997). This vaccine was able to reduce intramammary infection rates but did not offer full protection.…”

Značaj Vakcinacije U Prevenciji Stafilokoknih Mastitisa Krava

“…Podeljena su mišljenja o aplikaciji vakcine u supramamarni limfni čvor, zbog jakog lokalnog zapaljenja limfnog čvora, koji otiče i veoma je bolan (Nordhaug, 1994;Hoedermaker, 1999). Zbog toga se sve više istraživača opredeljuje za davanje vakcine parenteralno-subkutano u regiju vrata ili subkutano u regiju limfnog čvora, jer je takav način jednostavan za aplikaciju, a izbegnute su i lokalne reakcije tkiva na vakcinu (Giraudo, 1997;Watson, 1996).…”

“…Eksperimentalne grupe od 1 do 5 su primile inaktivisanu bakterijsku ćeliju S. aureus (10 10 bakterija u dozi), nosač vakcine je bio aluminijum hiodroksid (grupe 1, 2, 4, 5) i komercijalni nosač vakcine (grupa 3). Eksperimentalne grupe 6, 7, 8 i 9 u sastavu vakcine su primile površinski polisaharid S. aureus-a u dozi od 2 mg, a nosači su bili liposomal (6,7,9) i mikropartkule u grupi 8. Kontrolna grupa nije primila vakcinu, već samo fosfatni pufer.…”