The objective of the present study was to evaluate the immunoprotection given by two vaccination programs in broilers, using comercial vaccines against the infectious bursal disease virus (IBDV). In group A, the strain 2512 (intermediate plus) was inoculated at 19 days of age; in group B was used two intermediate-intermediate vaccines: the strain 2512 at day 10 and the strain 228TC at day 19; and group C was used as the nonvaccinated control group. The three groups were challenged at day 32 with the standard strain F52/70 of IBDV. The protection was measured after the challenge through clinical signs (diarrhea), size of the bursa, bursal index, productive parameters and antibody titers. The size and the bursal index at 7 days post challenge in the three groups showed bursal atrophy but this, did not significantly affect productive parameters. Groups A and B had similar body weights and a...

El objetivo del presente estudio fue evaluar la inmunoprotección conferida por dos programas de vacunación en pollos de carne, con diferentes vacunas comerciales del virus de la Enfermedad Infecciosa de la Bursa (EIB). El grupo A fue vacunado con la cepa 2512 (intermedia-fuerte) a los 19 días de edad; el grupo B fue vacunado a los 10 días con la cepa 2512 (intermedia-intermedia) y a los 19 días con la cepa 228TC (intermedia-intermedia); y el grupo C fue el control no vacunado. Los tres grupos fueron desafiados a los 32 días de edad con la cepa estándar F52/70 de la EIB. La protección fue medida a través de signos clínicos (diarrea), tamaño de la bursa, índice bursal, lesiones histopatológicas en bursa, parámetros productivos y títulos de anticuerpos. El tamaño e índice bursal al 7o día del desafío en los 3 grupos fueron compatibles con atrofia bursal, aunque no afectar...

The present work evaluated the mortality, removal, and discarded rates in broilers of two commercial genetic lines, reared in three consecutive cycles of 45-49 days each under similar management conditions. In each cycle, 360 birds per genetic line (A and B) were used. Necropsy was carried out to dead and removed birds. Removed birds were those that showed severe growth delay and discarded birds were those that showed injuries or abnormalities at the end of the cycle. In both lines, the main causes of mortality were the ascites syndrome and sudden death syndrome. Line B showed higher mortality rate during the first cycle (p<0.05), but there was no statistical difference in the removal and discarded rates between the two genetics lines. The main cause for removing birds in both lines was leg problems, mainly chondrodystrophia. In general, it can be concluded that productive performance...

The present work evaluated the mortality, removal, and discarded rates in broilers of two commercial genetic lines, reared in three consecutive cycles of 45-49 days each under similar management conditions. In each cycle, 360 birds per genetic line (A and B) were used. Necropsy was carried out to dead and removed birds. Removed birds were those that showed severe growth delay and discarded birds were those that showed injuries or abnormalities at the end of the cycle. In both lines, the main causes of mortality were the ascites syndrome and sudden death syndrome. Line B showed higher mortality rate during the first cycle (p<0.05), but there was no statistical difference in the removal and discarded rates between the two genetics lines. The main cause for removing birds in both lines was leg problems, mainly chondrodystrophia. In general, it can be concluded that productive performance...

Aflatoxins cause a variety of disorders in poultry, especially affecting the liver (aflatoxicosis). Contaminated livers may become a health risk to consumers when expended in food markets. The purpose of the present study was to detect the presence of aflatoxins in chicken livers in Lima food markets. Samples were collected in 16 markets located in various socioeconomic sectors of Lima. From every market livers were subclassified as normal and apparently suspicious. Analysis of 32 samples was conducted at the Laboratory of Biochemistry, Nutrition and Animal Feeding, Veterinary Medicine Faculty, San Marcos University. Aflatoxins were determined through the ELISA method approved by the AOAC Research Institute, using the Veratox HS (high sensitivity, 0, 1, 2, 4, and 8 ppb). Liver samples are quite complex so immunoaffinity extraction columns (NEOCOLUMN for aflatoxins, 04/08) were used. The ...

This study was carried out to evaluate the influence of environmental temperature and humidity on productive performance of Cobb-Vantress 500 broiler chickens reared for 45 days under an open broiler house during the winter and summer seasons (2004). The trial comprised 720 1-day-old chickens (360 chickens per season using 5 repetitions of 34 males and 38 females each). Body weight, body weight gain, feed consumption, feed conversion index, mortality, body size uniformity, and productive efficiency index were evaluated. Weekly body weight and body weight gain were statistically different between birds reared in winter and summer (p<0.05). The higher temperature during summer affected feed consumption, body weight and productive efficiency index but did not affect feed conversion index. The rearing of broiler chickens, both males and females, during the summer season as compared to win...

The present research work evaluated the results of 390 serum samples collected to birds reared in commercial farms (broilers, egg-laying hens, and breeders) and 343 serum samples collected to birds reared in non-technical farms (backyard and fighting birds) that were analyzed by the hemoagglutination inhibition (HI) test for the Newcastle disease (ND). Samples were collected by the SENASA (national authority for animal health) as part of a national serological survey in the second semester of year 2001. An interpretation table for the results of the HI test was designed by a team of experts taking into consideration the number and type of vaccines against ND used. The prevalence rate of birds with antibody titers compatible to a Newcastle virus challenge was 1.8 ± 1.3% in birds from commercial farms and 9.9 ± 3.2% in birds from non-technical farms. The logistic regression analysis show...

The objective of the study was to determine the prevalence of antibodies against avian Paramyxovirus type 1 (APMV-1) in backyard turkeys (n=388) in four provinces of Lima, Peru (Lima, Huaral, Huaura, and Barranca). Blood samples were collected from August to December 2008 and analyzed by hemagglutination inhibition test. The resulting seroprevalence was 3.9% as 15/388 turkeys showed antibody titers consistent with a viral challenge of APMV-1. The highest frequency of positive samples (10/15) was observed in the province of Lima, whereas none sample was positive in the Barranca province. It is concluded that backyard turkeys in three provinces of Lima were exposed to some strains of PMVA-l, constituting a reservoir of virus.

The objective of this study was to evaluate the presence of antibodies against Reticuloendotheliosis virus (REV) in flocks of layers hens using commercial ELISA kits. A total of 630 serum samples from 42 flocks in production of 28 commercial farms in the department of La Libertad and the province of Lima were collected from July 2004 till March 2005. The results indicated that 33.3% (14/42) flocks were seropositive [22.2% (6/27) in Lima and 53.3% (8/15) in La Libertad respectively], and without significant association between the infection and history of tumor problems, age, and genetic line. This is the first study conducted in commercial layer hens and the results showed the presence of the REV in Peru.

The present study aimed to evaluate the effect of treating broiler litter with active aluminosilicate on productive parameters of broiler chickens. Four hundred broilers Ross 308 of both sexes were reared for 44 days. Half of them were reared on litter treated with aluminosilicate and the other half on untreated litter. Productive performance of chicks and ammonia concentrations, atmospheric ph, litter ph, and moisture ratio of the litter were evaluated on a weekly basis. Additionally, lesions in breast and foot pads were also evaluated. Body weight gain, feed conversion index, and productive efficiency index were statistically similar between the two groups. No breast lesions were observed and the degree of lesions in foot pads was similar in the two groups. The ammonia concentrations, atmospheric ph, and litter ph were higher in the non-treated litter group showing that the litter trea...

This study was carried out to evaluate the influence of environmental temperature and humidity on productive performance of Cobb-Vantress 500 broiler chickens reared for 45 days under an open broiler house during the winter and summer seasons (2004). The trial comprised 720 1-day-old chickens (360 chickens per season using 5 repetitions of 34 males and 38 females each). Body weight, body weight gain, feed consumption, feed conversion index, mortality, body size uniformity, and productive efficiency index were evaluated. Weekly body weight and body weight gain were statistically different between birds reared in winter and summer (p<0.05). The higher temperature during summer affected feed consumption, body weight and productive efficiency index but did not affect feed conversion index. The rearing of broiler chickens, both males and females, during the summer season as compared to win...

El objetivo del presente estudio fue determinar la presencia de anticuerpos contra el virus de la Reticuloendoteliosis (REV) en lotes de gallinas ponedoras utilizando la prueba de ELISA con kits comerciales. Se tomaron 630 muestras de suero, entre julio de 2004 a marzo de 2005, de 42 lotes en producción de 28 granjas comerciales del departamento de La Libertad y la provincia de Lima. Se encontró el 33.3% (14/42) de lotes seropositivos, siendo 22.2% (6/27) en Lima y 53.33% en La Libertad, sin encontrar asociación estadística de la infección con antecedentes de problemas tumorales, grupo etáreo y línea genética. Este es un primer estudio realizado en gallinas ponedoras comerciales cuyos resultados evidencian la presencia del REV en el Perú.

El estudio evaluó el efecto del tratamiento de la cama con un aluminosilicato activado sobre los parámetros productivos en pollos de carne. Se utilizaron 400 pollos de carne de ambos sexos de la línea Ross 308. La mitad se crió sobre cama tratada con aluminosilicato y la otra mitad sobre cama no tratada hasta los 44 días de edad. Se analizó los datos productivos de las aves, niveles de amoniaco y pH atmosférico del gallinero, y pH y porcentaje de humedad de la cama. También se evaluó la presencia de pododermatitis y lesiones a nivel de la pechuga. La ganancia de peso, el índice de conversión alimenticia y el índice de eficiencia productivo europeo fueron estadísticamente similares entre los dos grupos. No se evidenció lesiones a nivel de la pechuga y el grado de lesiones a nivel de las patas fue similar en ambos grupos. El nivel de amoniaco, pH atmosférico y pH de la cama ...

Se evaluó la influencia de la temperatura y humedad medioambiental sobre los parámetros productivos de pollos de carne de la línea Cobb-Vantress 500 criados por 45 días bajo el sistema de galpón abierto durante las estaciones de invierno y verano del 2004. Se utilizaron 720 pollos (360 aves por estación, empleándose 5 repeticiones con 34 machos y 38 hembras por grupo). Se evaluó el peso corporal, ganancia de peso, consumo de alimento, índice de conversión alimenticia, mortalidad,uniformidad de peso corporal e índice de eficiencia productivo. Hubo diferencias significativas (p<0.05) entre las campañas de verano e invierno con relación al peso y ganancia de peso semanal. La mayor temperatura en el verano afectó el consumo de alimento, la ganancia de peso y el índice de eficiencia productiva, pero no el índice de conversión alimenticia. La crianza de pollos de carne, tan...

Se evaluó la influencia de la temperatura y humedad medioambiental sobre los parámetros productivos de pollos de carne de la línea Cobb-Vantress 500 criados por 45 días bajo el sistema de galpón abierto durante las estaciones de invierno y verano del 2004. Se utilizaron 720 pollos (360 aves por estación, empleándose 5 repeticiones con 34 machos y 38 hembras por grupo). Se evaluó el peso corporal, ganancia de peso, consumo de alimento, índice de conversión alimenticia, mortalidad,uniformidad de peso corporal e índice de eficiencia productivo. Hubo diferencias significativas (p<0.05) entre las campañas de verano e invierno con relación al peso y ganancia de peso semanal. La mayor temperatura en el verano afectó el consumo de alimento, la ganancia de peso y el índice de eficiencia productiva, pero no el índice de conversión alimenticia. La crianza de pollos de carne, tan...

Se analizaron los resultados de la prueba de inhibición de la hemoaglutinación (HI) para la enfermedad de Newcastle (ENC) realizada en 390 sueros de aves de crianza industrial (pollos de carne, ponedoras comerciales y reproductoras) y 343 sueros de aves de crianza no tecnificada (aves de riña y crianza casera), colectados por el Servicio Nacional de Sanidad Agraria (SENASA) durante un monitoreo serológico realizado en el 2001. Se diseñó una tabla de interpretación de resultados de la prueba HI para la ENC teniendo en cuenta el número y tipo de vacunas aplicadas a cada ave. Se obtuvo una prevalencia de aves con títulos de anticuerpos compatibles a un desafío con el virus de la ENC de 1.8 ± 1.3% en la crianza industrial y de 9.9 ± 3.2% en la crianza no tecnificada. El análisis de regresión logística mostró que la crianza no tecnificada representa un factor de riesgo (p<0...

El objetivo del presente estudio fue determinar la prevalencia de anticuerpos contra Paramixovirus Aviar Tipo 1 (APMV-1) en pavos de crianza familiar (n=388) en cuatro provincias del departamento de Lima (Lima, Huaral, Huaura y Barranca), Perú. Las mues- tras fueron colectadas durante los meses de agosto a diciembre de 2008, y fueron anali- zadas mediante la prueba serológica de Inhibición de la Hemoaglutinación. Se encontró una prevalencia de 3.9%, observándose que 15/388 pavos presentaron títulos de anticuerpos compatibles a un desafío viral con cepas de campo del PMVA-1. La mayor frecuencia de muestras positivas (10/15) se observó en la provincia de Lima, mientras que no se tuvo muestras positivas en la provincia de Barranca. Se concluye que los pavos de crianza familiar de tres provincias de Lima estuvieron expuestos a alguna cepa de PMVA-l, constituyendo un reservorio del v...

Aflatoxins cause a variety of disorders in poultry, especially affecting the liver (aflatoxicosis). Contaminated livers may become a health risk to consumers when expended in food markets. The purpose of the present study was to detect the presence of aflatoxins in chicken livers in Lima food markets. Samples were collected in 16 markets located in various socioeconomic sectors of Lima. From every market livers were subclassified as normal and apparently suspicious. Analysis of 32 samples was conducted at the Laboratory of Biochemistry, Nutrition and Animal Feeding, Veterinary Medicine Faculty, San Marcos University. Aflatoxins were determined through the ELISA method approved by the AOAC Research Institute, using the Veratox HS (high sensitivity, 0, 1, 2, 4, and 8 ppb). Liver samples are quite complex so immunoaffinity extraction columns (NEOCOLUMN for aflatoxins, 04/08) were used. The ...

This study evaluated the protection conferred by a vaccine against Gumboro disease in laying hens. Three hundred Isa Brown one-day-old chicks were equally distributed in three groups. Groups A and B were vaccinated, twice, at 9 and 24 days old with an intermediate-intermediate strain (2512), and group C remained unvaccinated. Groups B and C were challenged at 32 days old with the F52/70 strain through the eye. Bursal index, bursa/spleen relationship and microscopic lesions of the bursa, spleen and thymus after vaccination were evaluated at 1, 35 and 45 days old. Antibody titers by an indirect ELISA study but not in birds of groups A and B. The bursal index values in the three groups were compatible with bursal atrophy. Histopathological lesions were severe in the three groups. At 45 days of age, birds of group C had the major seroconvertion (3997), while groups A and B presented similar ...

The study evaluated the presence of the Newcastle disease virus in the Albufera de Medio Mundo lagoon, situated north of Lima. The lagoon is inhabited for various wild migrant bird species. Three sampling periods were conducted of six weeks each, colleting 900 fresh fecal samples from 11 species. Samples were inoculated in specific-pathogen free (SPF) embryonated eggs of 10 days of age for isolation of the virus. The hemagglutinant activity of the allantoic fluid showed negative results in all samples. The estimated prevalence calculated through a beta simulation was 0.1% with a distribution between 0.002 and 0.4%. The prevalence was too low for considering these birds as a possible source of infection toward domestic birds.