Host Immune Responses Against Hog Cholera Virus in Pigs Treated with an Ionized Alkali Mineral Complex

To determine the immune responses in pigs to hog cholera virus after treatment with an ionized alkali mineral complex (IAMC), 40 healthy pigs (28-32 days old) from a commercial swine farm were purchased and housed into 4 groups (n=10 each). All pigs were vaccinated intramuscularly (1 ml) with an attenuated live hog cholera virus (HCV, LOM strain) at 28-32 days old and challenged with a virulent hog cholera virus at 8 weeks after vaccination. Each group was treated with PowerFeelTM sprayed diet as 0.05% (w/w) in a final concentration (T-1, n=10), a diet mixed with SuperFeedTM as 3% (w/w) in a final concentration (T-2, n=10), or a diluted PowerFeelTM solution (1:500, v/v) as drinking water (T-3, n=10), respectively. A group (n=10) served as a non-treated control. Proportions of expressing CD2+ and CD8+ cells increased significantly (p<, 0.05) at 8-week post-application. Mean antibody titers of each group against HCV gradually increased to higher levels after vaccination and with challenge of the virulent virus. In conclusion, the IAMC-treated diets can be helpful for the improvement of growth in pigs with proper vaccination program, while the IAMC-treated diets have no effects on the clinical protection against hog cholera.

Relation between lymphocyte subpopulations of peripheral blood and immune responses of modified live hog cholera virus vaccine in pigs treated with an ionized alkali mineral complex

Thirty-nine healthy pigs (28-32 days old) were purchased from a commercial swine farm and housed at swine pens of the College. The animals were vaccinated intramuscularly (1 ml) with an attenuated live hog cholera virus (HCV, LOM strain) and then boostered at 5 weeks after the first vaccination. The animals were divided into 4 experimental groups: 0.05% (w/w) PowerFeel-supplemented diet (T-1, n = 10); 3% (w/w) SuperFeed-supplemented diet (T-2, n = 10); diluted PowerFeel solution (1 : 500, v/v) as drinking water (T-3, n=9); control (n=10). PowerFeel is an original form of ionized alkali mineral complex (IAMC) and SuperFeed is a commercial product of IAMC. The subpopulation of lymphocyte in blood was assayed by a flow cytometry and HCV-specific antibody was determined by an indirect immunofluorescence assay. In IMAC-treated groups, the proportions of subpopulation expressing MHC-class II, CD2+, CD4+, CD8+, and surface IgM+ B lymphocytes were significantly decreased at 5-weeks after the first vaccination. Significant decreases were also observed in the proportions of MHC-class II, CD2+ and CD8+ lymphocyte at 3-weeks after the booster injection. The humoral immune responses in T-1 and T-2 groups were greater than those in T-3 or control group. These results suggest that IAMC-supplemented diets may have an HCV-specific immunostimulatory effect in pigs.

Development and standardization of an indirect ELISA for the serological dianosis of classical swine fever

Um ensaio imunoenzimático do tipo ELISA indireto (ELISA-I) foi desenvolvido e padronizado para o diagnóstico sorológico de peste suína clássica. Na comparaçäo foram utilizadas novecentas e trinta e sete amostras de soros suínos, as quais foram testadas pelo teste de soroneutralizaçäo seguido de revelaçäo por imunoperoxidase (NPLA), tomado como padräo, resultando em 223 amostras positivas e 714 negativas. Em relaçäo ao NPLA, o ELISA-I apresentou sensibilidade de 98,21 por cento, especificidade de 92,86 por cento, valor preditivo positivo de 81,11 por cento, valor preditivo negativo de 99,4 por cento e precisäo de 94,1 por cento. A análise estatística dos resultados revelou uma correlaçäo muito forte (r=0,94) entre os dois testes. Quando comparado com um "kit" de ELISA disponível comercialmente, a performance de ambos em relaçäo ao NPLA foi similar. Concluiu-se que o ELISA-I é um teste apropriado para triagem em larga escala de soros para a detecçäo de anticorpos contra o Vírus da Peste Suína Clássica (VPSC), embora näo seja capaz de diferenciar entre anticorpos induzidos pelo VPSC ou outros pestivírus

Alteraciones de la concentración de leucocitos y subpoblaciones de linfocitos de cerdos que sobrevivieron al desafío con el virus de la fiebre porcina clásica / Changes in leucocyte and lymphocyte subpopulations of pigs that survived classical swine fever virus challenge

La infección con el virus de la fiebre porcina clásica (FPC) provoca la disminución de todas las subpoblaciones de leucocitos circulantes y una inmunosupresión marcada en los cerdos que se enferman y mueren. Sin embargo, no se ha informado del efecto del virus sobre los leucocitos circulantes en cerdos que sobreviven a la infección. Con objeto de conocer este efecto se estudiaron 6 cerdos que, después de ser desafiados experimentalmente con el virus de la FPC, desarrollaron la enfermedad, pero posteriormente se recuperaron. Los parámetros evaluados en estos cerdos fueron los signos clínicos, la temperatura rectal, la biometría hemática y las subpoblaciones del linfocitos determinadas por rosetas de eritrocitos. Los resultados mostraron que hubo un incremento en la temperatura rectal desde el día siete haste el día doce posinoculación, asociada a anorexia, decaimiento y diarrea ligera. En los primeros siete días hubo una disminución marcada de la concentración de leucocitos totales, linfocitos, leucocitos polimorfonucleares segmentados y en banda, monocitos, linfocitos T totales (TE), T de alta afinidad (Taa). B con receptor fc (Bfc) y Null. Al mismo tiempo se observó un incremento de T autólogos (Taut), que son células inmaduras, y no hubo alteración de los linfocitos B con receptor de complemento (Bc). Sin embargo, a partir del séptimo día se incrementaron los valores de la mayoría de las células y disminuyeron los Taut. Estos resultados indican que la recuperación de los animales estuvo asociada al incremento de los leucocitos circulantes