Reduced dietary protein level influences the free amino acid and gene expression profiles of selected amino acid transceptors in skeletal muscle of growing pigs.

This study was conducted to evaluate the effect of reduced dietary protein level on growth performance, muscle mass weight, free amino acids (FAA) and gene expression profile of selected amino acid transceptors in different fibre type of skeletal muscle tissues (longissimus dorsi, psoas major, biceps femoris) of growing pigs. A total of 18 cross-bred growing pigs (Large White × Landrace × Duroc) with initial body weight (9.57 ± 0.67 kg) were assigned into three dietary treatments: 20% crude protein (CP) diet (normal recommended, NP), 17% CP diet (low protein, LP) and 14% CP diet (very low protein, VLP). The results indicated improved feed-to-gain ratio was obtained for pigs fed LP and NP diets (p < 0.01), while the pigs fed VLP diet showed the worst growth performance (p < 0.01). There was no significant difference in the weights of longissimus dorsi and psoas major muscle between LP and NP groups (p > 0.05). Majority of the determined FAA concentration of LP group were greater than or equal to those of NP group in both longissimus dorsi and psoas major muscle (p < 0.01). Further, the mRNA expression levels of sodium-coupled neutral amino acid transceptor 2, L-type amino acid transceptor 1 and proton-assisted amino acid transceptors 2 were higher in skeletal muscle tissue in LP group compared to those of the pigs fed NP or VLP diet. These results suggested that reduced dietary protein level (3 points of percentage less than recommended level) would upregulate the mRNA expression of amino acid transceptors to enhance the absorption of FAA in skeletal muscle of growing pigs. There seems to be a relationship between response of AA transceptors to the dietary protein level in skeletal muscle tissue of different fibre type. To illustrate the underlying mechanisms will be beneficial to animal nutrition.

Effects of dietary garlic (Allium sativum Linn) supplementation on body weight and gut morphometry of commercial broilers / Efectos de la suplementación dietética de ajo (Allium sativum Linn) sobre el peso corporal y la morfometría intestinal de los pollos de engorde comercial

The effect of garlic on the absorptive surface of the small intestine of broilers was investigated towards elucidating its mechanism of growth promotion. One hundred day-old Arbor acre broilers were reared in 4 separate groups of twenty-five each. Broiler diet was supplemented with graded doses of garlic meal viz: 0 percent - group A; 0.125 percent - group B; 0.25 percent - group C; 0.5 percent - group D. Feed conversion ratio (FCR) was determined at 6 week-old. At 8 week-old, five broilers/group were selected randomly, euthanized and sections of the jejunum were harvested for histological examination. Villi lengths, widths and cryptal depths were determined. Mean body weight at 8 weeks old was highest in group B (1930 +/- 41g) and least in group A (1850 +/- 92g). FCR was highest in group D (4.34) and least in group B (3.8). Mean villi length, villi width and cryptal depth were highest (p<0.05) in group B i.e. 39.3 +/- 2.3 mm, 7.64 +/- 1.6 mm and 23.0 +/- 1.6 mm, respectively, indicating increased absorptive surface area. It was concluded that garlic meal supplementation at 0.125 percent in the diet of commercial broilers improved body weight gain and FCR by increasing villi length, villi width and cryptal depth.

Fue investigado el efecto del ajo sobre la superficie de absorción del intestino delgado de pollos de engorde para dilucidar su mecanismo de promoción del crecimiento. Cien pollos pollos de engorde Arbor acres de cien días de edad fueron criados en 4 grupos. La dieta de los pollos se complementó con dosis graduales de ajo en: 0 por ciento - el grupo A; 0,125 por ciento - el grupo B, 0,25 por ciento - el grupo C y 0,5 por ciento - el grupo de alimentación D. El índice de conversión alimenticia (ICA) se determinó a las 6 semanas de edad. A las 8 semanas de edad, 5 pollos de cada grupo fueron seleccionados al azar, se eutanizaron y secciones del yeyuno fueron preparadas para el examen histológico. Fueron determinadas la longitud y el ancho de las vellosidades, junto a la profundidad de las criptas. La media de peso corporal a las 8 semanas fue mayor en el grupo B (1930 +/- 41 g) y menor en el grupo A (1850 +/- 92 g). El ICA fue mayor en el grupo D (4,34) y menor en el grupo B (3,8). La media de longitud de las vellosidades, ancho de las vellosidades y profundidad de las criptas fueron mayores (p <0,05) en el grupo B es decir, 39,3 +/- 2,3 mm, 7,64 +/- 1,6 mm y 23,0 +/- 1,6 mm, respectivamente, indicando mayor área de superficie de absorción. Se concluyó que los suplementos de ajo en concentración del 0,125 por ciento en la dieta de los pollos de engorde comerciales mejoró la ganancia de peso corporal y el ICA mediante el aumento de longitud y ancho de las vellosidades, junto a la profundidad de las criptas.

Comparative susceptibility of chickens, turkeys and ducks to infectious bursal disease virus using immunohistochemistry.

Twenty chicks, 12 turkey poults and 10 ducklings, all 5 weeks old were infected with 2 x 10(3.5) chick LD(50) IBD virus to determine the course of the virus in the 3 poultry species. Uninfected control birds were kept separately. Two infected and 2 control birds/species were euthanized at time intervals between 3 and 168 hours post infection (pi). Sections of thymus, bursa of Fabricius, spleen, liver, kidney, proventriculus and ceacal tonsil were stained for the detection of IBD virus antigen using immunoperoxidase technique. IBD virus antigen positive cells stained reddish-brown and the amount of such cells in tissue sections were noted and scored. Stained cells were present in all organs examined for up to 168 hours pi in the 3 poultry species except ceacal tonsils of ducks at 72 and 120 hours pi. Antigen score was highest in chickens and least in ducks as reflected by average of total scores/sampling time of 12, 10.8 and 8 in chickens, turkeys and ducks respectively. Total antigen score/sampling time in infected chickens peaked twice; 24/48 and 144 hours pi, whereas such bi-phasic peaks were absent in turkeys and ducks. Range of total antigen score at different sampling times was 7-17.5 in chickens, 10-13 in turkeys and 7-10 in ducks indicative of marked viral replication in chickens. Presence of IBD viral antigen in organs of all 3 poultry species is indicative of infections. The innate ability of turkeys and ducks to prevent appreciable replication of IBD virus after infection requires further investigation.

Isolation and preliminary characterization of chicken anemia virus from chickens in Nigeria.

Chicken anemia virus (CAV) was isolated for the first time from the Nigerian chicken population. The virus was recovered from necropsied birds from broiler and pullet flocks that suffered disease outbreaks tentatively diagnosed as infectious bursal disease. A sensitive polymerase chain reaction (PCR) assay detected CAV DNA in tissues of necropsied birds. Restriction endonuclease analysis performed with the 733-bp PCR product and the Cfo I enzyme indicated at least two different CAVs were circulating among the Nigerian chicken population. Four isolates were obtained from pooled liver and thymus tissues using the MDCC-MSB1 cell line. These isolates were found to be antigenically closely related to the Cuxhaven-1 (Cux-1) reference strain of CAV when reacted with four monoclonal antibodies prepared against the Cux-1 virus. One of the isolates (isolate A) induced thymus atrophy, bone marrow aplasia, and low hematocrit values when inoculated into 1-day-old specific-pathogen-free chickens. These findings not only demonstrate that CAV is present in Nigeria, but they also likely represent the first cell culture isolation of the virus in Africa.

Serological evidence of chicken anaemia virus infection in Nigerian indigenous chickens.

Serum samples from 20 out of 180 (11.1%) apparently healthy Nigerian indigenous chickens were negative for antibodies against chicken anaemia virus using the enzyme-linked immunosorbent assay (ELISA). Of the 160 positive sera (88.9%), 12 (7.5%) had titres ranging from 1500-3000, 46 (28.8%) had titres from 3000-5000 while 102 (63.8%) had titres between 5000-11000. The overall mean titre value was 5845 +/- 2402. This appears to be evidence of a natural outbreak of the infection since the chickens had no history of vaccination against any poultry disease.