Summaries
Relationship between egg shell breakage and laying hen housing systems – An overview
R.M.G. HAMILTON and W.L. BRYDEN
Egg shell breakage is and remains a source of economic loss to the egg producer. In general, about 3% of the eggs laid by hens housed in battery cages or in free-run systems have cracked shells. This number increases about another 1% for hens kept in enriched cages or housed free-range and a further 1 to 2 % for those in aviaries. The range of cracked shells reported was from 2 to 12%, but there were few published reports for most production systems. The occurrence of dirty shelled eggs is about 2 to 3% higher that the incidence of eggs with cracked shells. Shell breakage is also influenced by manufacturer of enrich cage systems. The highest impact eggs receive as they move from the hen to the retail store is in the laying house; overall, eggs receive impacts that average about 13G. The material used to make egg cartons (paper pulp or plastic foam), the cases in which the cartons are shipped (cardboard or wire), and the location of a carton within the shipping case (top, middle or bottom) affect the occurrence of shell breaking when eggs are transported. Even apparently weak impacts to egg shells may cause microcracks to develop and if the impacts are stronger visible cracks become apparent or they may rupture the mammillary membranes which will allow the egg’s content to escape.
Future demands of the poultry industry: Will we meet our commitments sustainably in developed and developing economies?
F.J. KLEYN and M. CIACCIARIELLO
The world’s population is expected to reach 9.8 billion people by 2050. Increases in population size, coupled with socio-economic changes such as urbanisation, age demographics, and increasing affluence levels, will double the demand for poultry products by 2050. The primary objective of agribusiness is to ensure food security for the global population at affordable prices. Concurrently, there is a desire that all food products be produced sustainably. The poultry industry is well-positioned to achieve adequate nutrient-dense food provision because chickens are efficient converters of energy and nutrients into edible product. Poultry production plays an essential role in local food security and the alleviation of poverty in the absence of other nutrient-dense foods. The poultry industry possesses the technology, skills and capital to meet the expected demand targets. However, the demand for poultry products that fulfil the environmental, social and financial standpoints of sustainability will increase. Public opinion will prevent us from using many of the technologies required to achieve these goals. Consumers will need to change their expectations, behaviour and spending patterns in the best interests of sustainability.
Commercial poultry feed formulation: current status, challenges, and future expectations
R.A. ALHOTAN
Poultry nutrition has evolved tremendously over the past 100 years. Feed formulation, the applied side of nutrition, has gone through vast improvements from simple hand formulations to computerised formulations using modern software equipped with advanced capabilities, which allows for high accuracy, easy integration, and flexibility. In general, the modern commercial feed formulations are based on the concept of ‘least-cost’ and produced using linear programming, which requires the user to have sufficient knowledge in the nutritional requirements of birds, and ingredient compositions and prices. Stochastic programming can also be used in high uncertainty situations, such as nutrient variation in feedstuffs, to increase the confidence of meeting the requirement of a particular nutrient. Although profit-maximising models were recommended to maximise profitability in poultry production, their use is still limited. Several challenges are encountered when formulating feeds such as nutrient variability, ingredient shortages, ingredient price fluctuations, antibiotic-free production, and meeting the requirements of constantly changing genotypes. Adopting innovative technology has helped nutritionists and mill managers overcome most of the challenges that they face. In the future, poultry feed formulation is likely to receive more enhancements like implementing the true protein and net energy system and considering advanced profit-maximising models. The feed formulation solutions’ suppliers are expected to introduce more high-tech enhancements to the formulation solutions in response to the growing demands of the feed industry. Such enhancements should maximise profitability, meet nutritional needs more accurately, and reduce environmental pollution for more sustainable poultry production.
Peripheral regulation of food intake in chickens -adiposity signals, satiety signals, and others
K. HONDA
Broiler chickens eat more feed and grow faster than layer chickens. However, hyperphagia-induced excessive accumulation of body fat in broiler chickens has become a serious problem in the modern poultry industry. Species specificity in terms of the physiological role of appetite-regulating hormones and neuropeptides can make it difficult to understand the mechanisms underlying the central regulation of food intake in chickens. Therefore, although the appetite regulatory system of chickens has been a focus of research in recent decades, the mechanisms underlying the hyperphagia of broiler chickens is not fully understood. Our previous studies demonstrated that peripheral hormones significantly suppress food intake in chicks. These findings suggest that postprandial elevation of peripheral anorexigenic hormones play important roles in appetite regulation in chickens. This review provides an overview of recent findings on the role of peripheral hormones in the regulation of food intake in chickens and propose the new insight of avian-species specific system of peripheral regulation of food intake and promising strategies for reducing body fat mass in broiler chickens.
Chick quality: An overview of measurement techniques and influencing factors
D. NARINÇ and E. AYDEMIR
The production quantity of poultry products is increasing in the world economy with every passing day. The increase in chick quality is synonymous with the increase in the number of saleable chicks in terms of the poultry industry. In addition, in order to obtain high-quality products, one should start production with high-quality chicks as well as providing the ideal environmental conditions starting from the first day of incubation. The additive gene effects on chick quality are very low, whereas environmental factors have a large effect. Environmental factors affecting chick quality can be classified as egg storage period and conditions, age and genotype of breeder flock, incubation conditions, incubation types and post-hatch handling. Both quantitative and qualitative methods are used to determine chick quality. The quantitative methods employed include such morphological measurements as chick weight, chick length, leg length, chest circumference, and the diameter of shank. The qualitative methods used to determine chick quality are visual assessment-based methods which are called the Pasgar score and the Tona score. In recent years, the Tona and Pasgar methods have been used frequently in studies carried out with respect to measuring the effects of various environmental practices on chick quality. This paper aims to review the studies carried out concerning chick quality, the factors influencing chick quality, and the determination of chick quality and makes some suggestions for future studies to be conducted on chick quality assessment.
Probiotics as therapeutic, antioxidant and immunomodulatory agents against poultry coccidiosis
M. MOHSIN, R.Z. ABBAS, G. YIN, Z. SINDHU, A. ABBAS, Z. HUANG, M.T. ALEEM, Z. SAEED, M.Z. AFZAL, A. EJAZ and M. SHOAIB
Avian coccidiosis is an important parasitic disease of birds, caused by genus Eimeria, and having great economic importance. The estimated global economic loss due to coccidiosis is up to US$3 billion annually. Approximately 80% of these losses are associated with performance parameters, including decreased weight gain, heavy mortality, poor feed conversion ratio and the remaining 20% of losses include the cost of prophylaxis and treatment measures. This disease has been controlled by different anticoccidial agents, but synthetic drug-resistance is the major issue due to which researchers are trying to develop modern alternate effective approaches. Moreover, drug residues cause health hazard issues for poultry product consumers, which have led to the cessation of such practices in developed countries. Control through vaccination can be considered as a good practice, but due to the high cost and complexity of Eimeria species, development of a cost-effective vaccine has proved challenging. Among other options, probiotics have shown favourable effects against coccidiosis. Use of probiotics can reduce 70-80% of losses faced by the poultry industry worldwide. They have shown excellent results due to their antioxidant, immunostimulatory and positive effects on intestinal health of infected birds. Furthermore, details about the expression of the host biological responses against poultry coccidiosis and how probiotic supplementation assists in improving these responses in chickens are described in this review.
Flavonoid antioxidants in chicken meat production: Potential application and future trends
F. RAFIEI and F. KHAJALI
Meat-type chickens (broilers) are highly prone to oxidative stress because of genetic selection for their growth rate and because of the environmental conditions in which they are reared. Oxidative stress has significant impacts on chicken meat quality and safety. As such, antioxidants are often added to the diets of chickens to prevent oxidative stress and to ensure the quality and safety of the meat. This paper discusses sources of oxidative stress (pro-oxidants) in the chicken meat industry, from the raising of live birds to the production of chicken meat. The potential of flavonoids – the biggest group of natural antioxidants – is also explored with a discussion of their natural sources, bioavailability, and their potential application in the chicken meat industry.
Olive pomace for the feeding of commercial poultry: effects on performance, meat and eggs quality, hematological parameters, microbiota and immunity
C.O. DE OLIVEIRA, A.A.P. ROLL, F.M. GONÇALVES, D.C.N. LOPES and E.G. XAVIER
The present study aims to gather the research carried out worldwide in the last two decades with the use of olive pomace in the diet of broilers, laying hens and laying quails to highlight the nutritional importance of such biomass and its effective use in poultry nutrition. The olive pomace from the extraction of olive oil has important chemical properties from a nutritional standpoint such as a high concentration of cellulose, hemicellulose and lignin. In addition, it can be a significant source of fatty acids (12 – 22%), minerals and phenolic compounds. Thus, combining the use of olive pomace and seeking to adapt it to animal feed in a sustainable way, research has been carried out around the world with the use of olive pomace in the diet of commercial birds. The results presented in different studies demonstrate that the inclusion of up to 10% of olive pomace in the diet of broiler chickens, commercial laying hens and Japanese quails does not negatively affect the performance of the birds and improves the quality of meat, such as odour and flavour. Additionally, an increase in the egg weight and yolk index has been observed when olive pomace is supplied up to 9% in diets. The inclusion of olive pomace can also alter the lipid profile of the chicken meat and egg yolk, increasing the series of monounsaturated fatty acids and reducing the saturated ones. Haematological parameters of the different categories of birds do not change regarding albumins, globulins, total proteins, haematocrit, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) with up to 20% olive pomace in the diet. The gut microbiota of birds that receive olive pomace in their feed is altered and broilers have better antibody titres for Infectious Bronchitis and Gumboro.
Effect of feeding fermented and non-fermented palm kernel cake on the performance of broiler chickens: A review
M.I. ALSHELMANI, U. KAKA, E.A. ABDALLA, A.M. HUMAM and H.U. ZAMANI
Palm kernel cake (PKC) is a by-product of oil extraction from palm fruits and has been included in poultry diets as an alternative to soybean meal and yellow corn. Due to its high content of fibre, coarse texture and gritty appearance, the use of PKC in poultry nutrition is limited. In order to increase the nutritive value of PKC, there is a tendency nowadays to create solid state fermentation (SSF) by using cellulolytic microbes. This paper reviews the impact of feeding fermented and non-fermented PKC on the performance of broiler chickens. Recent studies have reported that SSF by cellulolytic microorganisms improved the nutritive value of PKC. The nutrient digestibility has been increased significantly in PKC fermented using Paenibacillus polymyxya ATCC 842 or Weisella confusa SR-17b. The availability of valine, histidine, methionine and arginine was 70.42, 71.50, 71.92 and 81.15%, respectively, in PKC fermented using P. polymyxa ATCC 842. The digestibility of crude protein (CP) increased by 61.83% and 59.90% in PKC fermented using P. polymyxya ATCC 842 or W. confusa SR-17b, respectively. In addition, body weight gain (BWG) and feed conversion ratio (FCR) improved significantly in broilers fed 15% fermented PKC compared to those fed 15% non-fermented PKC (2000.43 g versus 1823.23 g and 1.75 versus 1.91, respectively). The intestinal Enterobacteriaceae decreased (4.03 CFU/g) and lactic acid bacteria increased (5.56 CFU/g) in birds fed 15% PKC fermented by P. polymyxa ATCC 842. Therefore, fermented PKC can be included in a broiler diet up to 15%, replacing part of soybean and yellow corn in the diet, leading to a decrease in the overall cost of poultry feeding.
Wealth from poultry waste: an overview
R. PRABAKARAN and S. EZHIL VALAVAN
Poultry production generates a huge volume of waste from hatchery, poultry farm, processing plant etc. which carry potential health hazards as they lead to air, water and land pollution. Disposal of these wastes by processing and recycling offers greater scope. Hatchery waste meal contains up to 44.63% of crude protein and 26.46% of crude fat and hence can be profitability used as an animal feed source. Appropriately processed dried poultry manure / litter would help in reducing the dependence on chemical fertilizers. India produces about 38.33 million tons of poultry manure annually sufficient to fertilize about 3.56 million hectares of farmland. While composting and combustion of poultry litter have been tried, biogas production could also be a good alternative. Poultry by-product meal (PBPM) obtained by rendering showed very high protein (63.7%) and fat (24.5%) contents and could be a cost-effective feed ingredient for monogastric animals that would also ensure efficiency of production. Biodiesel production from chicken fat by the transesterification process also offers good potential and India is keen on taking advantage by incorporating 5% of biodiesel in diesel to bring down its dependence on crude oil imports. Effective and efficient disposal of poultry waste will ensure sustainability of poultry production in developing countries.
Goose production and goose products
J. KOZÁK
Goose keeping can expand the choice of basic food materials and provides materials (feather and down) for light industry. There are various ways to produce goose meat using preferably white feathered breeds. Intensively reared broiler geese attain a slaughter weight of 5 kg by 56-63 days of age; under semi-intensive keeping they reach a slaughter weight of 6 kg by 16 weeks of age, and under extensive keeping (grazing) they can be slaughtered by 22-24 weeks of age. Fattened liver is produced with 9-24 weeks old liver type (Landaise) geese via cramming (force feeding) for 14-21 days by which time the liver weight can reach 600-1000 g. Goose fat is high in polyunsaturated fatty acids (PUFA) and along with goose meat can be considered as functional foods. The fattened goose liver is a delicacy, while goose eggs are mostly used as propagating material albeit with occasional consumption in some Asian countries. Most of the worldwide feather and down production originates from slaughtered geese; only 1-2% of the global production is removed manually. At scalding, the percentage of feather in body weight amounts to 3.8-5.5% in broiler vs. 3.4-5.3% in fattened goose, respectively. The feather and down obtainable from young geese (8-10 weeks old) per capita at their natural moulting time is 80-100 g on the first occasion. Six to seven weeks later it amounts to 100-130 g and after another 6-7 weeks 140-170 g, respectively. In the EU only those countries where it is and was a traditional practice are allowed to harvest feathers from and force feed geese. Some believe the objection and ban of these activities are scientifically unfounded.
Role of backyard poultry in South-East Asian countries: post COVID-19 perspective
P.K. DAS and I. SAMANTA
The potential growth of the poultry industry was halted globally during COVID-19 although poultry birds were not affected directly by the virus. Distress in the poultry industry during the pandemic is primarily due to restriction of movement imposed on various items such as poultry feed, chicks, medicine and vaccines, and poultry products both locally and globally particularly in Asia, where 10 countries executed national lockdowns and 12 countries employed localized lockdowns. Rumours about spreading of SARS-CoV-2 virus through poultry meat caused further collapse in the domestic market economy. The export market of poultry products has declined in certain regions like Asia, Europe and North America. It is expected that worldwide chicken meat trade may be lowered by 4 percent although there is increased demand for animal protein among consumers. Hence, an integrated approach is needed to revive the poultry industry. Apart from commercial poultry maintained in integrated farming systems with moderate to high level of biosecurity, there is a ‘backyard’ or ‘village level’ poultry sector with minimal biosecurity. In the backyard sector, native birds or locally available breeds are maintained and the birds or their products are mostly consumed locally. The strategy to adapt backyard poultry as an alternative system to generate income not only augments poultry production but also guarantees the availability of animal protein to the poorer section of the society, as well as improving the purchasing capacity of this section, and guards against the ‘reverse migration’ of labour during the post COVID-19 period. Furthermore, smallholders could play a vital role in fulfilling the demand for animal products in developing countries. Some initiatives to distribute chicks, feed and medicine for rearing among the marginal farmers were detected in India, Bangladesh and Cambodia during lockdown to mitigate the catastrophic effect of COVID-19 on the rural economy.
Kadaknath: A popular native chicken breed of India with unique black colour characteristics
S. HAUNSHI and L.L.L. PRINCE
Kadaknath is the most popular and unique native chicken breed of India. This breed is experiencing higher demand in recent times due to its unique characteristics and perceived health benefits of its meat and eggs. The entire bird including plumage, skin, shank, and internal organs is black. The black colour of this bird is due to hyperpigmentation associated with the fibromelanosis caused by the Fm gene. Three varieties of the Kadaknath breed have been identified based primarily on plumage colour: jet black, pencilled and golden. Kadaknath is a small-sized bird with small shanks (51.5 mm at 8 weeks). It attains the body weight of 865 g at 20 weeks. Cocks and hens weigh about 1500 and 1200 g, respectively, at 40 weeks. The average age at first egg is high (185 days) and the egg production potential of this breed is somewhat less (50 to 55 eggs in 40 weeks). Egg production up to 52 weeks was 90 to 105 eggs and the annual egg production is estimated to be in the range of 120 to 140 eggs. This breed has good fertility (80 to 85%) and hatchability (83 to 90%) status. Eggs are small in size (42 to 45 g) but have good shell quality (10.47% shell) with light brown to brown coloured shells, and low yolk to albumen ratio (0.51). Consumers prefer Kadaknath meat due to its desirable flavour and lean meat (0.11 to 0.52 % abdominal fat) as compared to broiler meat (1.74 to 1.85% abdominal fat). Increased demand for healthier meat among modern consumers has led to the rearing of Kadaknath birds in intensive and semi-intensive systems around the major cities in India. The current paper describes the growth, production, and reproduction performance, status of immune-competence, carcass characteristics, meat quality, egg quality traits and future research needs of the Kadaknath breed.