Polyhydroxyalkanoates (PHA) are naturally occurring biopolymers, obtained from microorganisms. Properties like biodegradability and biocompatibility make PHA a part of today's commercial polymer industry. However, the production cost of PHA has been a great barrier to extend its application to large scale production. Substrates and usage of pure cultures constitute the main reason for its high production cost. On the other hand, rapid industrialization i.e., industrial sectors such as sugar, pulp and paper, fruit and food processing, dairies, slaughterhouses, and poultries, has resulted in the generation of the huge quantity of wastes. Consequently, becoming large source of environmental pollution and health hazard. This review emphasizes on the usage of various waste feedstocks obtained from industrial and agricultural industries as an alternate substrate for PHA production. As these waste materials are rich in organic material and also microbes, they can be the good starting material for PHA production. Additionally, advantages and economic importance of mixed cultures and also PHA applications are discussed. Future prospects and challenges in PHA production from waste feedstocks are also highlighted.
The infectious bursal disease (IBD) is an acute immunosuppressive viral disease that significantly affects the economics of the poultry industry. The IBD virus (IBDV) was known to infect B lymphocytes and activate macrophage and T lymphocytes, but there are limited studies on the impact of IBDV infection on chicken intraepithelial lymphocyte natural killer (IEL-NK) cells. This study employed an mRNA sequencing approach to investigate the early regulation of gene expression patterns in chicken IEL-NK cells after infection with very virulent IBDV strain UPM0081. A total of 12,141 genes were expressed in uninfected chicken IEL-NK cells, and most of the genes with high expression were involved in the metabolic pathway, whereas most of the low expressed genes were involved in the cytokine-cytokine receptor pathway. A total of 1,266 genes were differentially expressed (DE) at 3 day-post-infection (dpi), and these DE genes were involved in inflammation, antiviral response and interferon stimulation. The innate immune response was activated as several genes involved in inflammation, antiviral response and recruitment of NK cells to the infected area were up-regulated. This is the first study to examine the whole transcriptome profile of chicken NK cells towards IBDV infection and provides better insight into the early immune response of chicken NK cells.
Due to the limitations in the range of antibodies recognising avian viruses, quantitative real-time PCR (RT-qPCR) is still the most widely used method to evaluate the expression of immunologically related genes in avian viruses. The objective of this study was to identify suitable reference genes for mRNA expression analysis in chicken intraepithelial lymphocyte natural killer (IEL-NK) cells after infection with very-virulent infectious bursal disease virus (vvIBDV). Fifteen potential reference genes were selected based on the references available. The coefficient of variation percentage (CV%) and average count of these 15 genes were determined by NanoString technology for control and infected samples. The M and V values for shortlisted reference genes (ACTB, GAPDH, HMBS, HPRT1, SDHA, TUBB1 and YWHAZ) were calculated using geNorm and NormFinder. GAPDH, YWHAZ and HMBS were the most stably expressed genes. The expression levels of three innate immune response related target genes, CASP8, IL22 and TLR3, agreed in the NanoString and RNA sequencing (RNA-Seq) results using one or two reference genes for normalisation (not HMBS). In conclusion, GAPDH and YWHAZ could be used as reference genes for the normalisation of chicken IEL-NK cell gene responses to infection with vvIBDV.
This study was conducted to evaluate the effect of dietary cottonseed oil (CSO) at
different levels on broiler chickens. Dietary CSO was tested for energy supplementation values in
poultry at levels 0, 3, 6 and 9% utilizing isonitrogenous (22.5% CP), semi-isocaloric (3100 Kcal/kg)
rations and run in the experiment. Ninety-six seven-day old unsexed Ross-308 broiler chicks with
an initial weight of 72.9 g were used for each experiment in a completely randomized design
(4x4x6). Chicks were fed for 42 days. Supplementation with the oils improved performance
(p>0.05) but CSO gave significant (p
Newcastle disease virus (NDV) is one of the most economically important avian virus which affects the poultry industry worldwide. Although NDV is being very actively studied in Malaysia, there are still no studies on its potential as an anticancer agent, a new approach to treating cancer known as virotherapy. Currently, a collaborative research is being undertaken between Universiti Putra Malaysia (UPM), Universiti Sains Malaysia (USM) and Majlis Kanser Nasional (MAKNA) in characterising various local NDV isolates as anticancer agent. This paper describes an overview of the research that have been carried out worldwide in the use of NDV for cancer treatment and also some of our findings in characterising local NDVs with oncolytic properties.
Ten strains of Salmonella weltevreden isolated from poultry sources were examined and found to contain plasmid DNA ranging in size from 1.8 to 68.5 MD. All isolates were susceptible to carbenicillin, cephalothin, ceftriazone, gentamicin, kanamycin and nalidixic acid, but resistance to bacitracin (100%), penicillin G (100%), rifampicin (100%), sulphamethoxazole (100%), cefuroxime (80%) and tetracycline (60%) was recorded. The 55 MD plasmid of strain SW5 determined resistance to penicillin G and tetracycline, which was transmissible to the E. coli K12 recipient at a frequency of 3.52 x 10(-5) transconjugants per input donor cell. The results of arbitrarily primed polymerase chain reaction (AP-PCR), using two 10-mer oligonucleotides and PCR-ribotyping to differentiate between the ten strains of S. weltevreden were compared. The strains were separated into ten different genome types by AP-PCR but were indistinguishable by PCR-ribotyping. These results suggest that poultry may constitute a reservoir for disseminating antibiotic resistance and that AP-PCR may be a valuable tool for epidemiological studies.
The in vivo action of the antimicrobial peptide melittin, expressed from a recombinant plasmid vector, on chickens experimentally infected with Mycoplasma gallisepticum was studied. The plasmid vector pBI/mel2/rtTA includes the melittin gene under the control of an inducible tetracycline-dependent human cytomegalovirus promoter and the gene coding for the trans-activation protein rtTA. Aerosol administration of the vector, followed by infecting the chickens with M. gallisepticum 1226, is shown to inhibit development of infection. The inhibitory action was confirmed by a complex of clinical, pathomorphological, histological and serological studies, and also by comparing the M. gallisepticum reisolation frequency from the respiratory tract and internal organs. The data suggest that plasmid vectors expressing genes of antimicrobial peptides can be considered as potential agents for the prevention and treatment of mycoplasma infections in poultry farming.
The phoretic association between Macrocheles muscaedomesticae and flies that inhabited poultry manure in a poultry farm in Sungai Buloh, Selangor, Malaysia was studied. The effects of temperature, relative humidity and fly abundance on phoretic rates also were investigated. The most abundant fly species found was Musca domestica; Musca sorbens, Chrysomyia megacephala and Ophyra chalcogaster were present in relatively large numbers. Representatives of ten families of mites were found on collected Mu. domestica. The most common mite was Ma. muscaedomesticae (Macrochelidae), found on all four species of flies mentioned above. The highest infestation (2.0%) occurred on O. chalcogaster but Mu. domestica had the highest average number infested (5.7). The ventral part of the housefly's abdomen was the most common site of mite attachment. Usually only one mite was found attached per fly. The highest phoretic rate recorded was 64.4 Ma. muscaedomesticae per 1000 Mu. domestica. There was no correlation between phoretic rates and Ma. muscaedomesticae abundance, nor was relative humidity a factor. However, a positive correlation was recorded in this host species between phoretic rates and temperature.
A stereological comparison has been made of the structure of the lungs of the adult female domestic fowl and its wild progenitor the Red Jungle Fowl. The volume of the lung per unit body weight of the domestic bird is between 20 and 33% smaller than that of the wild bird. The domestic fowl has partly compensated for this by increasing the surface area for gas exchange per unit volume of exchange tissue. However, the blood-gas tissue barrier is about 28% thicker in the domestic fowl than in the Red Jungle Fowl, and this has led to a 25% lower anatomical diffusing capacity for oxygen of the blood-gas tissue barrier per unit body weight in the domestic fowl. These structural characteristics may make the modern domestic fowl vulnerable to stress factors such as altitude, cold, heat or air pollution by predisposing to hypoxaemia and perhaps thence to ascites.
Chicken meat is widely consumed and it is the most common and popular poultry species in the world.The preference and consumption of chicken meat have been tremendously increasing in Malaysia. About 120 respondents who took part in the study were classified into four groups namely routine chicken eaters, chicken likers, chicken lovers with a health concern and real chicken lovers based on their preference and consumption of chicken meat. It is worthwhile to mention that the taste, price, and easy to cook were statistically significant between the four groups. In addition, race moderates the relationship with Malays dominating the chicken lovers’ category. It is interesting to observe that Malays prefer chicken meat with chilies, Chinese prefer chicken meat with sauce and Indians prefer chicken meat with salad.The findings of the study are useful to the broiler plants and agencies that are responsible in selling chicken meat. Further, the results may be used as a guide to the selection of chicken meat, and also to the restaurant owners in the selection of food to be offered to their consumers.
Caenorhabditis elegans (C. elegans) have been widely used as an infection model for mammalian related pathogens with promising results. The bacterial factors required for virulence in non-mammalian host C. elegans play a role in mammalian systems. Previous reported that Salmonella found in vegetable and poultry meat could be potential health hazards to human. This study evaluated the pathogenicity of various serovars of Salmonella enterica (S. enterica) that recovered from local indigenous vegetables and poultry meat using C. elegans as a simple host model. Almost all S. enterica isolates were capable of colonizing the intestine of C. elegans, causing a significant reduction in the survival of nematodes. The colonization of Salmonella in C. elegans revealed that the ability of S. enterica in killing C. elegans correlates with its accumulation in the intestine to achieve full pathogenicity. Using this model, the virulence mechanisms of opportunistic pathogenic S. enterica were found to be not only relevant for the interactions of the bacteria with C. elegans but also with mammalian hosts including humans. Hence, C. elegans model could provide valuable insight into preliminary factors from the host that contributes to the environmental bacterial pathogenesis scenario.
Imports are the only source of food supply to Singapore. Such condition offers a very attractive proposition for agricultural oriented countries. The dependence on type of food imports is determined by consumer demand. This study intends to do an exploratory study on the current conditions of Singaporean food consumption and expenditures with implications on Malaysia as an important agricultural exporting country to Singapore. It is identified that Singaporean consumers tend to demand for high quality poultry, pork, seafood, vegetables, and fruits in future, particularly in response to income growth. At the mean time, Malaysia is seemingly rich in the production of these food commodities and commits to exports for the excess of the supplies. While facing competition from various countries, Malaysia still possesses various competitive advantages over the other countries.
The effectiveness of poultry stunning in producing swift slaughtering was analysed in response to the time needed for the chickens to become insensible upon neck cutting (Td) and the induction of myofiber apoptosis. In total, 49 chicken broilers (BW of 2.17 ± .24 kg) were sacrificed with pre-slaughter stunning, using a constant voltage stunner where the electric current varied between 7.2 to 124.3 mA, and without stunning. The electric current applied during stunning was found to have no effect on Td. Number of apoptotic myonuclei did not vary among stunned and unstunned meat. Apoptosis inducing factor (AIF) and caspase 3 expressions were also not detected in the meat samples of both stunned and unstunned groups at 1 d postmortem. Since the slaughtering process and stunning are associated with stress, the expression of 70 kDa-heat shock protein (Hsp70) was investigated. Moreover Hsp70 is also an inhibitor of apoptosis, by preventing the activation of AIF and apoptosome which stimulates caspase 3 activation. However, expression of Hsp70 was not induced in both stunned groups and unstunned groups. Together, this study found that poultry stunning does not affect Td and myofiber apoptosis.
A new virus named Sitiawan virus (SV) was isolated from sick broiler chicks in chicken embryos. The virus replicated well with cytopathogenic effect (CPE) in the chicken B-lymphocyte cell line LSCC-BK3. The virus was an enveloped RNA virus of approximately 41 nm in size with hemagglutinating activity (HA) to goose erythrocytes. It was cross-reactive with Japanese encephalitis virus (JEV), a member of flaviviruses by HA inhibition tests but not by cross-virus neutralization tests. The cDNA fragment of NS5 gene was amplified with primers corresponding to NS5 gene of flaviviruses. The nucleotide sequences were 92% homologous to Tembusu virus, a member of the mosquito-borne virus cluster of the genus Flavivirus. In cross-neutralization tests with Tembusu virus, antiserum to SV did not neutralize Tembusu virus, and antiserum to Tembusu virus neutralized more weakly to SV than against homologous virus. These results indicate that SV is a new virus which can be differentiated serologically from Tembusu virus but is otherwise similar with respect to nucleotide sequence. The virus causes encephalitis, growth retardation, and increased blood glucose levels in inoculated chicks.
The present study proposes a system for co-composting food waste and poultry manure amended with rice husk biochar at different doses (0, 3, 5, 10%, w/w), saw dust, and salts. The effect of rice husk biochar on the characteristics of final compost was evaluated through stabilization indices such as electrical conductivity, bulk density, total porosity, gaseous emissions and nitrogen conservation. Results indicated that when compared to control, the biochar amendment extended the thermophilic stage of the composting, accelerated the biodegradation and mineralization of substrate mixture and helped in the maturation of the end product. Carbon dioxide, methane and ammonia emissions were reduced and the nitrogen conservation was achieved at a greater level in the 10% (w/w) biochar amended treatments. This study implies that the biochar and salts addition for co-composting food waste and poultry manure is beneficial to enhance the property of the compost.
A series of plasmids containing the HSP70 gene of Mycobacterium tuberculosis fused to the hemagglutinin (H5) gene of H5N1 avian influenza virus (AIV) (H5-HSP70 (heat shock protein 70) vaccine) or individual H5 gene (H5 vaccine) or HSP70 gene (HSP70 vaccine) were constructed based on the plasmid pcDNA3.1. Expression of H5 gene in Vero cells in vitro and in chickens in vivo was confirmed following their transfection and immunization with H5 or H5-HSP70 vaccines. Controls consisted of HSP70 vaccine, empty plasmid pcDNA3.1 and co-administered H5 and HSP70 vaccines. H5-HSP70 vaccine produced in chicken higher hemagglutination inhibition (HI) antibody titer than H5 vaccine. However, the increase was not statistically significant. We have demonstrated for the first time that the H5 DNA vaccine with fused HSP70 gene may produce an enhanced induction of humoral immune response to AIV in chickens.
The transmission of highly pathogenic avian influenza H5N1 virus to Southeast Asian countries triggered the first major outbreak and transmission wave in late 2003, accelerating the pandemic threat to the world. Due to the lack of influenza surveillance prior to these outbreaks, the genetic diversity and the transmission pathways of H5N1 viruses from this period remain undefined. To determine the possible source of the wave 1 H5N1 viruses, we recently conducted further sequencing and analysis of samples collected in live-poultry markets from Guangdong, Hunan, and Yunnan in southern China from 2001 to 2004. Phylogenetic analysis of the hemagglutinin and neuraminidase genes of 73 H5N1 isolates from this period revealed a greater genetic diversity in southern China than previously reported. Moreover, results show that eight viruses isolated from Yunnan in 2002 and 2003 were most closely related to the clade 1 virus sublineage from Vietnam, Thailand, and Malaysia, while two viruses from Hunan in 2002 and 2003 were most closely related to viruses from Indonesia (clade 2.1). Further phylogenetic analyses of the six internal genes showed that all 10 of those viruses maintained similar phylogenetic relationships as the surface genes. The 10 progenitor viruses were genotype Z and shared high similarity (>/=99%) with their corresponding descendant viruses in most gene segments. These results suggest a direct transmission link for H5N1 viruses between Yunnan and Vietnam and also between Hunan and Indonesia during 2002 and 2003. Poultry trade may be responsible for virus introduction to Vietnam, while the transmission route from Hunan to Indonesia remains unclear.
A total of 225 samples from poultry farms and the surrounding environment were screened for vancomycin-resistant enterococci (VRE) and bifunctional aminoglycoside-resistant enterococci using conventional microbiological tests and a nanoplex polymerase chain reaction (PCR) assay. Three (1.3%) of the samples were found to contain vancomycin-resistant isolates (MIC>256 microg/mL) that had a vanA genotype. The three vanA positive VRE isolates were identified as different species. Only one isolate (Enterococcus faecium F 4/13_54) was sensitive to teicoplanin (MIC<0. 12-0.35 microg/mL); the other two VRE (E. faecalis A 21_35 and E. gallinarum F 5/10_1) were resistant to teicoplanin (MIC 3.6-->16 microg/mL). The vanC genotype was observed in nine (4%) of the samples collected. High-level gentamicin-resistant (HLGR) enterococci (with MIC ranging between 100 and 500 microg/mL) were detected in 44 samples. However, only 40 of these were found to possess the aac(6')-aph(2'') gene. The overall prevalence of VRE among the samples from the poultry farms and environment was 5.3%, but the prevalence of the clinically significant vanA VRE was 1.3%, and the prevalence of bifunctional aminoglycoside-resistant enterococci was slightly higher, at 19.5%.
Avian infectious bronchitis (IB) is a widely distributed poultry disease that has huge economic impact on poultry industry. The continuous emergence of new IBV genotypes and lack of cross protection among different IBV genotypes have been an important challenge. Although live attenuated IB vaccines remarkably induce potent immune response, the potential risk of reversion to virulence, neutralization by the maternal antibodies, and recombination and mutation events are important concern on their usage. On the other hand, inactivated vaccines induce a weaker immune response and may require multiple dosing and/or the use of adjuvants that probably have potential safety risks and increased economic burdens. Consequently, alternative IB vaccines are widely sought. Recent advances in recombinant DNA technology have resulted in experimental IB vaccines that show promise in antibody and T-cells responses, comparable to live attenuated vaccines. Recombinant DNA vaccines have also been enhanced to target multiple serotypes and their efficacy has been improved using delivery vectors, nanoadjuvants, and in ovo vaccination approaches. Although most recombinant IB DNA vaccines are yet to be licensed, it is expected that these types of vaccines may hold sway as future vaccines for inducing a cross protection against multiple IBV serotypes.
Matched MeSH terms: Poultry; Poultry Diseases/immunology*; Poultry Diseases/prevention & control