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1.
Groups of pigs from vaccinated and unvaccinated sows were vaccinated once or twice between the ages of eight and 20 weeks with a commercial inactivated, oil adjuvanted Aujeszky's disease virus vaccine. Pigs were challenged by the oronasal route when 22 to 27 weeks old. Pigs from unvaccinated sows developed neutralising antibodies after vaccination but no seroconversion was detected in eight-week-old pigs or in 80 per cent of 15-week-old pigs from vaccinated sows. Challenge resulted in severe disease and weight loss in control pigs. In vaccinated animals the duration and severity of clinical signs and the amount of weight lost decreased with increasing serum neutralisation titres. The results indicate that parenteral vaccination at weaning with the vaccine described will not protect pigs at slaughter age against infection and disease, particularly if they were born from seropositive mothers.  相似文献   

2.
A vaccine containing inactivated cultures of Bordetella bronchiseptica, toxigenic Pasteurella multocida type D and dermonecrotic P multocida type D toxoid in an oil-in-water adjuvant was given to seven sows, with seven others acting as controls. Half the piglets in each litter were exposed intranasally when four days old to B bronchiseptica and when eight days old to toxigenic P multocida type D. There was considerably less sneezing in the litters of the vaccinated sows and when the piglets were 10 weeks old, only 18 per cent had deformed snouts compared with 74 per cent in the litters of the control sows. The average liveweight gain of the piglets born to vaccinated sows was significantly better (P less than 0.05) between two and 10 weeks of age than that of the piglets born to unvaccinated sows, although there were no significant lower respiratory tract lesions in either group. The conchal atrophy scores were significantly lower (P less than 0.001) in the piglets from the vaccinated sows and were negatively correlated (r = -0.37) with increasing liveweight gain. In the liters of the vaccinated sows, P multocida was not isolated from the nasal passages of the in-contact piglets and from only 7 per cent of those deliberately exposed compared with 65 per cent and 79 per cent, respectively, in the litters of the control sows. P multocida was isolated post mortem from the tonsils of 23 per cent of the piglets of vaccinated sows and from 87 per cent of those from unvaccinated sows.  相似文献   

3.
Six-week-old piglets, born of unvaccinated sows, were vaccinated against foot-and-mouth disease (FMD) with a trivalent, inactivated vaccine containing an adjuvant or vaccinated against classical swine fever (CSF) with a live attenuated vaccine or against both diseases simultaneously at two different sites. The antibody response to the FMD vaccine was not significantly influenced by the simultaneous vaccination against CSF. FMD vaccine administered simultaneously with the CSF vaccine produced a significantly higher antibody response to CSF than occurred with CSF vaccination only.  相似文献   

4.
The efficacy of a new vaccine against atrophic rhinitis in pigs was tested in the Netherlands and Denmark. The vaccine contained protein dO (a truncated Pasteurella multocida toxin which is immunogenic and non-toxic), inactivated Bordetella bronchiseptica whole cells, and an adjuvant. The sows were either vaccinated intramuscularly with 2 ml of the vaccine at six to eight and two to four weeks before expected farrowing or left unvaccinated as controls. All the piglets were challenged intranasally with B bronchiseptica when three to seven days old and with P multocida three to four days later. Pigs born to the vaccinated sows performed significantly better than pigs born to the control sows when judged on growth, average daily weight gain and snout scores. The challenge organisms were reisolated more frequently from the control pigs than from the pigs in the vaccinated group. The vaccinated sows and their progeny developed high titres of antibodies against B bronchiseptica and P multocida toxin.  相似文献   

5.
The influence of age and maternal immunity on the development and duration of postvaccinal humoral response against swine influenza viruses (SIV) were investigated under experimental conditions. Piglets born to immune and non-immune sows were vaccinated twice with bivalent inactivated vaccine. Vaccination was done according to 5 different schedules: 1+4, 1+8, 4+8, 8+10 or 8+12 weeks of age. Antibodies to the haemagglutinin type 1 and 3 were determined using the haemagglutination inhibition (HI) test. Maternally derived antibodies (MDA) against H1N1 and H3N2 in the serum of unvaccinated piglets born to immune sows were above the positive level until about 13-14 and 9-10 weeks of life, respectively. No serological responses were seen in any of the groups after the first vaccination. After the second dose of vaccine production of antibodies was observed even before the complete disappearance of maternal antibodies. MDA, however, were associated with reduced antibody response. In MDA-negative piglets, an active humoral postvaccinal response was developed in all vaccinated pigs. The age at which the vaccine was given was associated with the differences in the magnitude of antibody response to SIV. In general those pigs that were vaccinated for the first time at the age of 1 week, developed lower maximum titres after the second vaccination, and become seronegative earlier than pigs that were vaccinated for the first time at 4 or 8 weeks of age.  相似文献   

6.
The neonatal requirements for maternal passive immunity and the lactation immunobiology with regard to sow immunisation for neonatal protection are reviewed. A vaccination protocol which combines oral and parenteral antigen administration to produce antibody activity mediated mainly by IgM is described. Its efficacy in affording protection to neonatal piglets was tested against a lethal oral infection with a virulent strain of Escherichia coli "Abbottstown". Piglets suckled on vaccinated or non-vaccinated sows were exposed to an infective challenge in the gastrointestinal tract and the relative pathology in test and control groups observed over the neonatal period. Death ensued in 76 per cent of piglets suckled on control sows and 26 per cent of piglets suckled on sows vaccinated by two intramuscular injections. Litters suckled on orally vaccinated sows were able to resist a similar infective challenge, there being only one fatality out of 42 piglets.  相似文献   

7.
Swine fever. Immunisation of piglets   总被引：4，自引：0，他引：4  
Vaccination against Swine Fever using the CL Chinese strain can be done in 7-day-old piglets if they are born of non-immune sows. The simultaneous weaning and vaccination emphasises the safety of this strain. The excellent immunity observed confirms the immunocompetence of 7-day-old piglets. In piglets born of immune sows and also weaned at 7 days, passive protection can extend beyond the age of 2 months if the sow is vaccinated several months prior to gestation. The immune level of the piglets would seem to depend on the interval between vaccination of the sow and farrowing and can be attributed to the quality of the antibodies transmitted by the colostrum. Piglets born of sows vaccinated 10 months prior to farrowing can be vaccinated as early as 5 weeks; the protection percentage observed at the age of about 6 months is over 80%. A booster injection at this age then confers immunity to future breeders throughout their economic life, i.e. 4 years in the reported experiment.  相似文献   

8.
Lameness in piglets up to nine weeks old was studied in a research station herd for four years; 9411 piglets were born alive, of which 9.8 per cent were treated for lameness. In litters born to gilts, 9.9 per cent of the piglets were treated for lameness, in litters born to sows of parity 3, 11.4 per cent of the piglets were treated, but in litters born to sows of parity 4 to 7 the proportion of piglets treated for lameness decreased to about 8 per cent. Around 75 per cent of all cases were observed in piglets less than three weeks old; the incidence risk of lameness decreased from 2.7 per cent during the first week of life to 0.3 per cent after weaning. The average weight of affected piglets was reduced by approximately 8 per cent at nine weeks of age. There was no overall association between lameness and sex or birth weight within sex. The mortality among lame gilts was higher at all ages than among healthy gilts, but among barrows a higher mortality was observed only during the late suckling period. Litters with 12 or more piglets had a higher incidence of lameness. Clinical signs of disease in the sow and whether the piglets were given an intramuscular injection of 200 mg of iron on their second, third or fourth day of life had no effect on the incidence of lameness.  相似文献   

9.
A vaccine of rotavirus and K99 antigen from enterotoxigenic Escherichia coli was emulsified in oil adjuvant and administered intramuscularly to pregnant cows. Calves born to and reared on vaccinated dams were protected against experimental rotavirus infection at five days old when compared with calves from unvaccinated control cows. Field trials of the vaccine were carried out in 40 commercial herds, in which half the cows in each herd were selected at random for vaccination and half were left unvaccinated. In 31 herds (2641 cows) there was no significant diarrhoea problem (less than 10 per cent morbidity); these herds were excluded from further analysis. The nine remaining herds did experience a calf diarrhoea problem of greater than 10 per cent morbidity, but on four farms the disease was associated with cryptosporidiosis and on a fifth no enteropathogens were detected; these five farms (461 cows) were also excluded from further analysis. Of the remaining four herds, two beef suckler herds (105 cows) had concurrent rotavirus and cryptosporidial infections, and vaccination was associated with a decreased excretion of rotavirus but not with a decreased incidence of diarrhoea. In the other two dairy herds (68 cows) with prevaccination rotavirus problems, there was a significantly decreased incidence of diarrhoea in calves born to vaccinated cows. No natural field challenge of enterotoxigenic E coli was encountered on any of the trial farms.  相似文献   

10.
Ten pregnant gilts were divided into two groups of five and one group was vaccinated at 80 and 95 days of pregnancy with a commercial bacterin containing Haemophilus parasuis serovars 2, 3 and 5. Half the piglets born to each group of gilts were vaccinated at seven and 21 days of age with the same bacterin, and one week after they were weaned at five weeks, all the piglets were inoculated intratracheally with 10(6) colony-forming units of Hparasuis serovar 5. At slaughter, a significantly smaller percentage of the lungs of the pigs born to the vaccinated gilts was affected by pneumonic lesions, and significantly fewer of them had arthritic joint changes. The average daily liveweight gain of the pigs born to the vaccinated gilts was significantly greater than that of those born to the unvaccinated gilts, but the vaccination of the piglets had no effect. There was no significant difference between the feed conversion ratios of the four groups of piglets, and none between the average times they took to reach slaughter weight. The pigs born to the vaccinated gilts had higher ELISA titres to Hparasuis than those born to the unvaccinated gilts.  相似文献   

11.
Three pairs of sows were vaccinated against foot-and-mouth disease (FMD) at various intervals before farrowing and samples of blood were collected from their piglets periodically for 70 days after birth. When the sows were vaccinated 12 to 13 days before farrowing the predominating FMD neutralising antibody at time of parturition was IgM and the observed half lives of the maternally derived antibodies in the piglets were short (four to eight days). However, when sows were last vaccinated 30 to 32 days before farrowing, the maternally derived FMD neutralising antibodies in the piglets were predominantly IgG and the observed half lives were seven to 21 days. These observed half lives for IgG were shown to be closely related to the period over which the maternally derived antibodies could be demonstrated and to the rate of increase of the piglet's blood volume over the same period. If corrections were made for increase in blood volume the decay rate of IgM antibodies in piglets was seven to 18 days while the decay rate for IgG was greater than 408 days. This result suggested that there was little or no IgG catabolism or excretion during the first 70 days of the piglet's life.  相似文献   

12.
This study was designed to evaluate the efficacy of an inactivated vaccine based on a European-type strain of porcine reproductive and respiratory syndrome virus (PRRSV) against the reproductive form of the syndrome in breeding gilts, and any congenital disease in their piglets. Five gilts were vaccinated twice, following the manufacturer's instructions, before they were inseminated. Nine additional gilts remained unvaccinated and served as positive (five gilts) and negative (four gilts) controls. A European wild-type strain genetically divergent from the vaccine strain was used to challenge the five vaccinated and five unvaccinated positive control gilts at 90 days' gestation. The vaccination of the five seronegative gilts did not produce any clinical signs or adverse reactions. However, the vaccine failed to prevent the clinical signs associated with PRRSV infection, viraemia after the challenge and transplacental infection of their piglets. The reproductive performance of the vaccinated gilts was similar to that of the unvaccinated positive controls, and there were no statistically significant differences in most of the parameters tested. However, the preweaning mortality of the piglets born to the vaccinated gilts was significantly lower than that of the piglets born to the positive control gilts.  相似文献   

13.
The trial involved eight large white sows obtained from a closed experimental specific pathogen free herd. Four sows (two each for an experimental vaccine and for Nobi-Vac AR) were vaccinated twice (eight weeks and two weeks before parturition) with 2 ml of vaccine administered intramuscularly. Two unvaccinated sows were used as an infected control group and two unvaccinated sows served as an uninfected control group. Forty-six piglets (28 from vaccinated sows and 18 from unvaccinated sows) were challenged by intranasal instillation of Bordetella bronchiseptica at two days of age and Pasteurella multocida type D, dermonecrotic toxin at seven days of age. Among the infected control group some piglets died and there were clinical signs of pneumonia and severe turbinate atrophy. In the vaccinated groups the results showed that immunisation of the pregnant sows had provided a good level of antibodies, which were transmitted to their offspring. There was a significant reduction in the clinical signs and no lesions were observed in the group vaccinated with the experimental vaccine and only moderate atrophy of the turbinates in the Nobi-Vac AR group. B bronchiseptica and P multocida were never recovered from the lungs of the vaccinated groups and in the nasal cavities their frequency declined with age.  相似文献   

14.
Surveys in three areas with emergency vaccination programmes revealed that 86-94% of the pigs vaccinated in the initial mass campaign had developed an adequate antibody titre against swine fever as compared with 29-55% of the pigs involved in supplementary vaccination campaigns. The serological response of piglets born from immunised sows rose with the age of vaccination from 11% at 5-6 weeks to 42% at 7-8 weeks and 77% at 9-10 weeks. In piglets born from immunised sows, a 50% 'take' of the vaccine was not obtained before the age of 8-9 weeks. Re-vaccination of gilts born from immunised dams improved the immune status to almost the level observed after mass campaigns. To strengthen herd immunity in vaccination areas, the age of supplementary vaccination has been raised to 7-9 weeks, while breeding gilts are re-vaccinated when 6-7 months old.  相似文献   

15.
Several Aujeszky's disease virus (ADV) vaccination protocols of sows were evaluated with regard to the passive protection conferred on piglets in a recently built commercial farm. Three different groups of sows were vaccinated using a Bartha K-61 strain. One group received an inactivated vaccine during pregnancy and the other two groups received attenuated vaccines, either during pregnancy (day 65) or on the seventh day of lactation. At farrowing, sows vaccinated during lactation had lower seroneutralization titres than those vaccinated during pregnancy either with inactivated or attenuated vaccines. Accordingly, their piglets were the ones with lower levels of maternally transferred neutralizing antibodies. At 4 weeks of age, five piglets born of each group of sows were challenged intranasally with a neurotropic strain of ADV. Piglets born of sows vaccinated during pregnancy with inactivated and attenuated vaccines gained 1.50 kg bodyweight and 2.50 kg bodyweight during 7 days, respectively, and did not show clinical signs, while piglets from sows vaccinated during the previous lactation lost 0.60 kg and presented moderate to severe clinical signs of ADV. Vaccination of sows during pregnancy provided more protection against ADV for piglets than sow vaccination before mating. Piglets born from sows vaccinated with attenuated or inactivated vaccines did not present remarkable differences on protection.  相似文献   

16.
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)  相似文献   

17.
The possible effect on pig protection after vaccination pregnant sows and their piglets against FMD at various age was examined using the SN test. Three experiments were conducted with three sow in each (8-9 piglets each). In the first experiment sows were not vaccinated but their piglets were vaccinated on 10th, 20th and 60th day of age. In second experiment sows were vaccinated at the end of rest period and in the middle of pregnancy. Pigs from one sow were vaccinated on 10th, from second sow on 20th and from the third sow on the 60th day of age. Pigs which were vaccinated on the 10th and 20th day of age were revaccinated on the 60th day of age. In third experiment sows were vaccinated at the end of the rest period and in the middle of pregnancy. Their piglets were not vaccinated. The conclusion may be drawn that if the epidemiological situation requires, systemic vaccination of all pigs then, on large farms (where pig production is planned) all sows should be vaccinated at the end of the rest period (first vaccination) and on the 55th-60th day of pregnancy. The next vaccination should be done in the middle of the next pregnancy. A vaccination program of piglets, according to our results, should depend on the vaccination program used for their dams.  相似文献   

18.
The purpose of the study was to investigate whether, on farms with both post-weaning multisystemic wasting syndrome (PMWS) and porcine reproductive and respiratory syndrome (PRRS), the PRRS vaccination of sows and their fattening pigs protects against these syndromes. In a farrow-to-finish pig farm with a history of PRRS and PMWS, 200 gilts and sows were allocated to one of two groups of equal size. The first group (C-sow group) was used as untreated controls, while the animals of the second group (V-sow group) were vaccinated with live Porcilis PRRS vaccine. At the next weaning, all piglets of half the sows of the C sow group were vaccinated once at 35 days of age with the vaccine (CV group), while the offspring of the other half of the unvaccinated sows were left unvaccinated (CC group). Similarly, the offspring of half the sows of the V sow group were vaccinated (VV group), while those of the other half of the vaccinated sows were left unvaccinated (VC group). No significant differences in morbidity were observed between the groups during the nursery and finishing phases, while morbidity in the growers was significantly reduced in the CV- and VV-groups (P < 0.05). Growers' mortality was significantly reduced after piglet vaccination when compared with unvaccinated pigs of unvaccinated dams (P < 0.05). Average daily gain and feed conversion ratio were significantly improved in vaccinated piglets compared with those in the unvaccinated groups (P < 0.05).  相似文献   

19.
In a field trial, the development of antibodies of a combined vaccine against the porcine parvovirus (PPV) as well as against swine erysipelas was compared with corresponding mono vaccines. Furthermore, these vaccines were used in different vaccination schedules. The tests were carried out on 109 gilts in three closed farms. In all gilts, a basic immunization repeated twice was carried out at the age of six months and at intervals of three weeks. The revaccination was carried out four months after the basic immunization with half of the animals, and six months after the basic immunization with the remaining gilts. Between the combined vaccine and the mono vaccine no significant differences in the development of antibodies against PPV could be found according to different vaccination schedules. The gilts having been vaccinated with the mono vaccine and boostered six months later showed significantly higher antibody titers against Erysipelothrix rhusiopathiae. Between the remaining vaccination groups no significant difference in the development of the antibodies against swine erysipelas could be found. On only one farm, a continuous decrease of antibody titers against PPV in case of altogether 238 non-vaccinated piglets until the sixth month of life could be observed. On the two other farms, an increase of antibody titers against PPV could be found at different points of time, which indicates an infection of the piglets. Between the individual vaccination groups no significant antibody titers against PPV could be measured in milk tests. With regard to the number of piglets born alive per litter, the number of piglets born dead per litter and the number of mummies, a significant difference could neither be found between the vaccination groups 1-4.  相似文献   

20.
The causes and timing of piglet mortality were studied in different farrowing systems. In the first experiment 198 litters were recorded in three systems, two of which allowed the sows to move freely, and the third restricted them in conventional crates. More piglets were weaned from the conventional crates than from the open systems and they grew more quickly. More than half the liveborn mortality occurred during the first four days after parturition. In the open systems, 17 per cent and 14 per cent of the piglets born alive were crushed, compared with only 8 per cent in the crates. In the second experiment, 29 sows and litters were studied in detail in a communal pen system during the first seven days of lactation. Three-quarters of the liveborn mortality was due to crushing. The total number of piglets dying per litter, including stillbirths, was significantly associated with the total litter size and the sow's parity. The percentage liveborn mortality was significantly associated with the parity and body length of the sows and with the within-litter variation in the birth weight of the piglets. Individual birth weight was closely associated with percentage survival. Only 28 per cent of piglets weighing less than 1.1 kg at birth survived to seven days.  相似文献   

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