Prospects for the utilization of Senna obtusifolia products as protein supplements for poultry

The scarcity and high cost of conventional ingredients are major factors limiting the growth of the poultry industry globally. This has driven research into alternative ingredients for poultry feeding. Senna obtusifolia or cassia, a widely distributed shrub, is invasive in many regions of the world. The seeds and leaves of the plant are moderate protein sources with the protein having an acceptable amino acid profile, especially essential amino acids. This nutritional profile of Senna obtusifolia products (seeds and leaves), coupled with their availability make them potential protein supplements for poultry feeding; however, the presence of several antinutritional factors (ANFs) (Oxalate, phytate, saponins, tannins and haemagglutinins) hinders their fullest use in the diet. In recent years, there has been increasing research interest into processing techniques to reduce the ANFs content and make these products safe for poultry feeding. Depending on birds age, fermented Senna seed meal may be included in the diet of broilers and cockerels up to 200 g/kg without compromising birds’ performance but raw meal as low as 50 g/kg exerts antinutritional effects. More research is needed into maximum utilization of Senna products to reduce cost of production on smallholder to medium scale poultry farms. Newer processing methods will need to be developed in response to the increasing market price of conventional protein sources.

Impact of commercial feed dilution with copra meal or cassava leaf meal and enzyme supplementation on broiler performance

A preliminary study investigated the impact of commercial feed dilution with copra meal (CM) or cassava leaf meal (CLM) and enzyme supplementation on broiler performance. Commercial feed alone (control) or diluted with CM and CLM at a concentration of 100 and 200 g/kg in the starter and finisher diets, respectively, was fed without and with Challenzyme 300A at a concentration of 300 g/tonne in 2 × 2 factorial arrangements with a control. Two hundred, 7-day-old male, Cobb 500 broiler chicks were randomly assigned to 5 diets containing 4 replicates of 10 birds each. There were no interaction or main effects (P > 0.05) on feed intake during either the starter or finisher phase. In the starter phase, feed-to-gain ratio (F:G) increased (P < 0.05) in the group fed with CM without enzyme. Enzyme supplementation restored F:G similar to the control. Diet dilution with CM or CLM had no effect (P > 0.05) on weight gain (WG) in the starter phase. Diluting the feed with CM or CLM without enzyme suppressed (P < 0.05) WG and F:G in the finisher phase, but enzyme supplementation restored the lost performances. There were no interaction or main effects (P > 0.05) on the carcass traits. Enzyme supplementation reduced (P < 0.05) feed cost per kilogram of carcass. Heavier ceca were observed in the group fed with dilution diets (P < 0.05). Enzyme supplementation reduced cecum weight in the group fed with CM (P < 0.05). The heaviest (P < 0.05) abdominal fat was recorded in the group fed with enzyme-supplemented CM diet, and the lightest (P < 0.05) abdominal fat was recorded in the group fed with CLM with enzyme. In the main effects, lighter (P < 0.05) liver, gizzard, and proventriculus were recorded in the group fed with control diet than in the group fed with the CLM diets, but the weight of these segments did not differ (P > 0.05) between the control and CM groups and between the fiber sources. The results suggest that dilution of commercial diet with CM or CLM may be a viable option for medium- and small-scale broiler production in the region. There is need for more research in the level of dilution, enzyme source, and concentration.

Immunization Coverage Surveys and Linked Biomarker Serosurveys in Three Regions in Ethiopia

Objective

Demographic and health surveys, immunization coverage surveys and administrative data often divergently estimate vaccination coverage, which hinders pinpointing districts where immunization services require strengthening. We assayed vaccination coverage in three regions in Ethiopia by coverage surveys and linked serosurveys.

Methods

Households with children aged 12–23 (N = 300) or 6–8 months (N = 100) in each of three districts (woredas) were randomly selected for immunization coverage surveys (inspection of vaccination cards and immunization clinic records and maternal recall) and linked serosurveys. IgG-ELISA serologic biomarkers included tetanus antitoxin ≥ 0.15 IU/ml in toddlers (receipt of tetanus toxoid) and Haemophilus influenzae type b (Hib) anti-capsular titers ≥ 1.0 mcg/ml in infants (timely receipt of Hib vaccine).

Findings

Coverage surveys enrolled 1,181 children across three woredas; 1,023 (87%) also enrolled in linked serosurveys. Administrative data over-estimated coverage compared to surveys, while maternal recall was unreliable. Serologic biomarkers documented a hierarchy among the districts. Biomarker measurement in infants provided insight on timeliness of vaccination not deducible from toddler results.

Conclusion

Neither administrative projections, vaccination card or EPI register inspections, nor parental recall, substitute for objective serological biomarker measurement. Including infants in serosurveys informs on vaccination timeliness.

Strategies for Coordination of a Serosurvey in Parallel with an Immunization Coverage Survey

A community-based immunization coverage survey is the standard way to estimate effective vaccination delivery to a target population in a region. Accompanying serosurveys can provide objective measures of protective immunity against vaccine-preventable diseases but pose considerable challenges with respect to specimen collection and preservation and community compliance. We performed serosurveys coupled to immunization coverage surveys in three administrative districts (woredas) in rural Ethiopia. Critical to the success of this effort were serosurvey equipment and supplies, team composition, and tight coordination with the coverage survey. Application of these techniques to future studies may foster more widespread use of serosurveys to derive more objective assessments of vaccine-derived seroprotection and monitor and compare the performance of immunization services in different districts of a country.