Blood and Gastrointestinal Parasites of Chickens and Turkeys Reared in the Tropical Rainforest Zone of Southeastern Nigeria

The blood and gastrointestinal (GI) parasites of chickens and turkeys reared in Owerri, Southeastern Nigeria were studied. Out of 5600 birds, 5040 (90%) were chickens and 560 (10%) were turkeys. Of these birds, 672 (12%) were infected with blood parasites, of which 448 (8.9%) were chickens and 224 (40%) turkeys. The blood parasites found in chickens were Leucocytozoon sp., with a prevalence rate of 448 (8.9%) occurring in both male and female chickens examined. Plasmodium sp. was found in the turkeys and it gave a prevalence of 224 (40%). 1792 (32%) of the birds were infected with faecal parasites, out of which, 1456 (28.9%) were chickens and 336 (60%) turkeys examined. Ascaridia sp. infected 1232 (24.4%) of the chickens and 336 (60%) of the turkeys were examined. The only cestode observed was Raillietina spp., which infected 224 (4.4%) of the chickens, but none in the turkeys. Generally, low blood and faecal infections were observed in the chickens, while infections in the turkeys were slightly higher.

Effect of protein sources on performance characteristics of turkeys in the first three weeks of life

The effect of nutrition during the early life of turkey poults has a long-lasting impact on bird performance.This study assessed the digestibility of 5 high protein feed ingredients(soybean meal [SBM],corn gluten meal [CGM],canola protein concentrate [CPC],fish meal [FM],and porcine meal [PCM]) in broiler chickens,as well as their use in turkey pre-starter diets fed to 21 d of age.The first experiment(5 × 2 factorial arrangement) determined nitrogen corrected apparent metabolizable energy(AMEn) and apparent ileal amino acid digestibility(AIAAD) of each ingredient in broiler chickens at 5 and 21 d of age,using 6 replications of 30 and 8 chicks,respectively.In the second experiment(completely randomized design),4 replication pens,containing 23 d-old poults,were randomly assigned to one of 5 dietary treatments.The diets were formulated based on the AMEn and AIAAD values derived in the first experiment,and consisted of a high SBM control diet,and 4 additional diets with either CPC,FM,PCM or CGM replacing 25% of the protein supplied by SBM in the control diet.Statistical analysis was completed using Proc Mixed in SAS 9.3.Planned contrasts were used to compare treatments in the second experiment.Trends were identified at P <0.10 and significant differences identified at P≤0.05.Bird age did not affect CPC,FM,CGM,and SBM AMEn,but the PCM value at d 5 was higher than that at d 21.Apparent ileal amino acid digestibility increased with age for most amino acids(AA),but the response was AA and protein source dependent.The largest average increase in AIAAD between 5 and 21 d of age was observed for CGM.Inclusion of CPC,FM,PCM,or CGM increased body weight up to 14 d,in comparison to poults fed the SBM diet,but feed efficiency and water consumption were not affected.Terminal ileum digesta moisture values were higher for birds fed SBM when compared to those fed PCM.These results demonstrate that combining SBM with CPC,FM,PCM,or CGM improves poult performance during the first 14 d of life in comparison to feeding SBM alone.

Mathematical modeling of the native Mexican turkey’s growth

Little is known about the productive performance of Mexican turkey, so the objective of the present study was to characterize growth performance curves of backyard turkey under a confined system. Forty fertile eggs were artificially incubated and turkey weight was recorded at hatch. During growth performance weekly weight was measured until 385 days of age. Turkey commercial feed and water were offered ad libitum. To characterize growth curves, a fourth degree polynomial model regression and a Richards biological model were used, which were compared by determination coefficient (r2), to reach the best fit model. The best fit model was the fourth degree polynomial regression model from a mathematical standpoint of view. It was found that maximum tom growth was reached at 15.7 weeks with a weight gain of 259.3 g/week and in hens at 12.4 weeks with a weight gain of 112.0 g/week. Body weight reached by toms at 40 weeks was 6 kg and hens at 35 weeks with 3.6 kg.

Protection by Recombinant Newcastle Disease Viruses (NDV) Expressing the Glycoprotein (G) of Avian Metapneumovirus (aMPV) Subtype A or B against Challenge with Virulent NDV and aMPV

Avian metapneumovirus (aMPV) and Newcastle disease virus (NDV) are threatening avian pathogens that can cause serious respiratory diseases in poultry worldwide. Vaccination, combined with strict biosecurity practices, has been the recommendation for controlling these diseases in the field. In the present study, we generated NDV LaSota vaccine strain-based recombinant viruses expressing the glycoprotein (G) of aMPV, subtype A or B, using reverse genetics technology. These recombinant viruses, rLS/aMPV-A G and rLS/aMPV-B G, were characterized in cell cultures and evaluated in turkeys as bivalent, next-generation vaccines. The results showed that these recombinant vaccine candi-dates were slightly attenuated in vivo, yet maintained similar growth dynamics, cytopathic effects, and virus titers in vitro when compared to the parental LaSota virus. The expression of the aMPV G protein in recombinant virus-infected cells was detected by immunofluorescence. Vaccination of turkeys with rLS/aMPV-A G or rLS/aMPV-B G conferred complete protection against velogenic NDV, CA02 strain challenge and partial protection against homologous patho-genic aMPV challenge. These results suggest that the LaSota recombinant virus is a safe and effective vaccine vector and expression of the G protein alone is not sufficient to provide full protection against aMPV-A or -B infections. Ex-pression of other aMPV-A or -B virus immunogenic protein(s) individually or in conjunction with the G protein may be necessary to induce stronger and more protective immunity against aMPV diseases.

Phytate and phosphorus utilization by broiler chickens and laying hens fed maize-based diets

Maize grain is primarily used as an energy source for poultry and other animals.Maize has relatively high phytate-P content and very low intrinsic phytase activity.Given that feed phosphates are produced from finite rock phosphate resources,a reduction in the use of feed phosphates in maize-based diets by increasing the utilization of plant P sources by animals is necessary to make poultry meat and egg production more sustainable.The utilization of P by poultry is affected by two intrinsic characteristics of maize:the concentration of inositol phosphates and the activity of the intrinsic phytase of the grain in the digestive tract.The objective of this review is to present data on the variation that exists in composition of maize relevant for P use and to address factors that influence P utilization in maize-based diets of poultry.Broiler chickens and laying hens have the potential to degrade phytate in the gastrointestinal tract,but this is depressed by high dietary Ca and P concentrations.Published values of phytate degradation in broilers are overall higher than those in laying hens.Differences also exist between broiler chickens and growing turkeys and Pekin ducks.The exogenous supplementation of microbial phytases and the introduction of transgenic high phytase maize in poultry diets are efficient not only for the improvement of phytate-P digestibility,production performance,egg quality and bone mineralization,but also for the reduction of P excreta to control environmental impact.