VERY few veterinary surgeons have thought fit to write a book on diseases of poultry. Mr. Ernest Gray has done justice to the subject and is to be congratulated on his effort. A book of this size, written by one with specialized knowledge, will add to the value of any library or private bookshelf. Diseases of Poultry Their Aetiology, Diagnosis, Treatment and Control; with a Section on the Normal Anatomy and Physiology of the Fowl. By Ernest Gray. (Lockwood's Agricultural and Horticultural Handbooks.) Pp. x + 198 + 16 plates. (London: Crosby Lockwood and Son, Ltd., 1940.) 9s. 6d. net.

Diseases of Poultry

Enterococci as probiotics and their implications in food safety

Coccidiosis is recognized as the major parasitic disease of poultry and is caused by the apicomplexan protozoan Eimeria. Coccidiosis seriously impairs the growth and feed utilization of infected animals resulting in loss of productivity. Conventional disease control strategies rely heavily on chemoprophylaxis and, to a certain extent, live vaccines. Combined, these factors inflict tremendous economic losses to the world poultry industry in excess of USD 3 billion annually. Increasing regulations and bans on the use of anticoccidial drugs coupled with the associated costs in developing new drugs and live vaccines increases the need for the development of novel approaches and alternative control strategies for coccidiosis. This paper aims to review the current progress in understanding the host immune response to Eimeria and discuss current and potential strategies being developed for coccidiosis control in poultry.

Poultry coccidiosis: recent advancements in control measures and vaccine development

With the increase in regulations regarding the use of antibiotic growth promoters and the rise in consumer demand for poultry products from ‘Raised Without Antibiotics’ or ‘No Antibiotics Ever’ flocks, the quest for alternative products or approaches has intensified in recent years. A great deal of research has focused on the development of antibiotic alternatives to maintain or improve poultry health and performance. This review describes the potential for the various alternatives available to increase animal productivity and help poultry perform to their genetic potential under existing commercial conditions. The classes of alternatives described include probiotics, prebiotics, synbiotics, organic acids, enzymes, phytogenics, antimicrobial peptides, hyperimmune egg antibodies, bacteriophages, clay, and metals. A brief description of the mechanism of action, efficacy, and advantages and disadvantages of their uses are also presented. Though the beneficial effects of many of the alternatives developed have been well demonstrated, the general consensus is that these products lack consistency and the results vary greatly from farm to farm. Furthermore, their mode of action needs to be better defined. Optimal combinations of various alternatives coupled with good management and husbandry practices will be the key to maximize performance and maintain animal productivity, while we move forward with the ultimate goal of reducing antibiotic use in the animal industry.

/pdf/alternatives-to-antibiotics-for-maximizing-growth-ljovix8alo.pdf

Alternatives to antibiotics for maximizing growth performance and feed efficiency in poultry: a review.

https://www.cell.com/trends/parasitology/pdf/S1471-4922(13)00164-5.pdf

Securing poultry production from the ever-present Eimeria challenge.

The effects of the probiotic PrimaLac (Lactobacillus acidophilus, Lactobacillus casei, Enterococcus faecium and Bifidobacterium bifidium) was investigated on performance and immune responses to vaccination against Newcastle disease and infectious bursal disease in broiler chickens. Use of PrimaLac significantly (P<0.05) enhanced broiler performance by improving body weight and decreasing the feed conversion ratio. Although administration of the probiotic appeared to improve the antibody responses to Newcastle disease virus and infectious bursal disease vaccination, the antibody titres of the probiotic-treated group were not significantly different from those not receiving probiotics.

https://www.tandfonline.com/doi/pdf/10.1080/03079450802356995

Effects of a multi-strain probiotic (PrimaLac) on performance and antibody responses to Newcastle disease virus and infectious bursal disease virus vaccination in broiler chickens.

Some haematological parameters (Differential WBC counts, total white blood cell count (WBC) and packed cell volume (PCV) percentages) and biochemical values (total protein, alkaline phosphatase, alkaline transferase, calcium, phosphorous, magnesium, glucose, triglyceride and cholesterol) of adult indigenous chickens compared with adult industrial broiler breeders (Ross 308). Differences among hematological parameter of Ross-308 and indigenous cocks and Ross-308 and indigenous hens were not significant except for PCV% of Ross-308 (32.60 ± 2.32) and indigenous hens (35.50 ± 2.22) (P<0.016). Comparison of biochemical parameters, showed significant differences only for cholesterol and glucose values between indigenous and Ross-308 hens. Glucose values in Ross-308 hens was higher than indigenous hens (274.50 ± 33.22 mg/dl and 245.60 ± 28.11 mg/dl, respectively) (P<0.026). In addition, cholesterol values in Ross-308 hens was higher than indigenous hens (181.50 ± 33.22 mg/dl and 152.60 ± 28.11 mg/dl, respectively) (P<0.026). No significant differences were observed between biochemical parameters values of Ross-308 and indigenous cocks.

Comparative study on blood profiles of indigenous and Ross-308 broiler breeders.

Partial protection against Eimeria acervulina and Eimeria tenella induced by synthetic peptide vaccine

One-day-old chicks (Cobb 500) were purchased from a commercial hatchery and raised on non-medicated diet in wire cages in coccidia-free conditions. The chickens were infected with a single dose (1 x 10(4)) of sporulated oocysts of E. maxima by direct injection into the crop at 5 weeks of age. Antibody capture immunoassay (ELISA) and lymphocyte proliferation assay were used for assessment of antibody and cellular responses, respectively. The results showed that both antibody and lymphocyte responses increased during the experiment and reached their highest level at 2 weeks post-inoculation, when they began to decline. A significant negative correlation between lymphocyte proliferation and oocyst output was observed. This study demonstrates that the whole-blood lymphocyte assay is a useful, relatively simple, sensitive and reliable technique for quantitative assessment of circulating T-cell responses. Assessment of lymphocyte proliferation and antibody responses may have applications in monitoring flock status in outbreaks of avian coccidiosis and evaluation of the efficacy of vaccination programmes in poultry.

https://www.tandfonline.com/doi/pdf/10.1080/03079459508419088

Alireza Talebi

Papers

Effects of a multi-strain probiotic (PrimaLac) on performance and antibody responses to Newcastle disease virus and infectious bursal disease virus vaccination in broiler chickens.

Comparative study on blood profiles of indigenous and Ross-308 broiler breeders.

Partial protection against Eimeria acervulina and Eimeria tenella induced by synthetic peptide vaccine

Correlation between immune responses and oocyst production in chickens monospecifically infected with Eimeria maxima.

Optimal conditions for measurement of blastogenic responses of chickens to concanavalin A in whole blood assays