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151.
Alternative poultry production with special reference to free range broilers has increased significantly since the nineties
in many regions of the world. Numerous factors influence the productive performance of this type of broilers: genotype (namely
the use of naked neck animals), feeding and access to an outdoor area. The aim of this paper is to study the influence of
each of these factors on the productive performance of free range broilers under commercial rearing conditions. A total of
3200, day old chicks of both sexes from naked neck and normally feathered genotypes were used in this trial. After a joint
initiation phase, animals were divided into four different treatments with the combination of two concentrates (high vs low
energy content) and management (access to outside park or not). Experiment lasted a total of 12 weeks. Live weight date was
recorded weekly and a samples of animals from the trial were sacrificed at the age of 8, 10 and 12 weeks, when carcass characteristics
were determined. Besides sex, the only factor that seems to affect growth characteristics was genotype as naked neck animals
had poorer growth rates than normally feathered. No effect was detected on carcass yields and percentages of carcass components
for any of the variables. From the data presented in this trial the practises associated with free range production are of
relative inconsequence to the technical animal production parameters and can only be justified by a pressing need to differentiate
these products from standard poultry products in what concerns both welfare issues and meat characteristics. The results also
indicate that genetic material from alternative poultry production in Europe can be a useful option in poultry production
development projects in the tropics. 相似文献
152.
Georgios Michailidis 《Veterinary research communications》2010,34(5):459-471
In recent years host antimicrobial peptides and proteins have been recognised as key mediators of the innate immune response
in many vertebrate species, providing the first line of defense against potential pathogens. In chickens a number of cationic
antimicrobial peptides have been recently identified. However, although these peptides have been studied extensively in the
avian gastrointestinal tract, little is known about their function in the chicken reproductive organs and embryos. Chicken
Liver Expressed Antimicrobial Peptide-2 (cLEAP-2) has been previously reported to function in protecting birds against microbial
attack. The aim of this study was to investigate the expression of cLEAP-2 gene in the chicken reproductive organs, as well
as in chicken embryos during embryonic development, and to determine whether cLEAP-2 expression in the chicken reproductive
organs was constitutive or induced as a response to Salmonella enteritidis infection. RNA was extracted from ovary, oviduct, testis and epididymis of sexually mature healthy and Salmonella infected birds, as well as from chicken embryos until day ten of embryonic development. Expression analysis data revealed
that cLEAP-2 was expressed in the chicken ovary, testis and epididymis as well as in embryos during early embryonic development.
Quantitative real-time PCR analysis revealed that cLEAP-2 expression was constitutive in the chicken epididymis, but was significantly
up regulated in the chicken gonads, following Salmonella infection. In addition, expression of cLEAP-2 during chicken embryogenesis appeared to be developmentally regulated. These
data provide evidence to suggest a key role of cLEAP-2 in the protection of the chicken reproductive organs and the developing
embryos from Salmonella colonization. 相似文献
153.
Martins G Penna B Hamond C Leite RC Silva A Ferreira A Brandão F Oliveira F Lilenbaum W 《Tropical animal health and production》2012,44(4):773-777
Despite the importance of small ruminants breeding in developing countries, milk/meat productivity remains unsatisfactory.
Infectious diseases, such as leptospirosis, brucellosis, and small ruminant lentiviruses (SRLVs), contribute to this scenario.
The objective of the present study was to determine the role of each of these diseases in the productivity of small ruminants
breeding in Rio de Janeiro, Brazil. In goats, 343 samples were tested for leptospirosis, 560 for Brucella abortus, and 506 for caprine arthritis-encephalitis (CAE), whereas in sheep, 308 samples were tested for leptospirosis, 319 for B. abortus, 374 for Brucella ovis, and 278 for Maedi-Visna (MV). Regarding leptospirosis, 25.9% of goats and 47.4% sheep were seroreactive, with serovar Hardjo
the most prevalent in both species. Anti-B. abortus agglutinins were found in 0.7% of all samples, exclusively in goats. In relation to SRLVs, 8.6% of goats and 3.2% of sheep
samples were positive for CAE and MV, respectively. Leptospirosis was the major infectious problem in the small ruminants
sampled and may contribute to impaired productivity of these animals. 相似文献
154.
Saeid R. Nourollahi Fard Masoud Asghari Fatemeh Nouri 《Tropical animal health and production》2009,41(8):1633-1636
The parasite of genus Sarcocystis is one of the most commonly found parasite in domestic animals worldwide. Some species of Sarcocystis cause important economic loss when causing clinical and sub clinical disease. The aim of this study was to determine the
prevalence of Sarcocystis in slaughtered Cattle in Kerman, Iran. The prevalence of Sarcocystis spp. infection was investigated in 480 cattle, slaughtered from May 2005 to February 2006 in the Kerman, Iran using naked
eye examination for macroscopic Sarcocysts, and peptic digestion, muscle squash, squeezing methods for microscopic types.
Muscles from heart, tongue, and esophagus, cervical and abdominal muscles of 480 slaughtered cattle were examined for Sarcocystis cysts. The prevalence of microscopic Sarcocystis cysts in cattle was detected in 100% and there was no macroscopic cyst in examined cattle. 相似文献
155.
Maryam Ansari-Lari Maryam Rezagholi Mahdie Reiszadeh 《Tropical animal health and production》2009,41(7):1283-1288
Purpose
To determine trends in calving ages and calving interval as measures of reproductive performance in Iranian Holsteins in Fars province, southern Iran during 2000–2005. 相似文献156.
Badrul Hasan Kamrul Islam Murshidul Ahsan Zakir Hossain Mahmudur Rashid Bibhas Talukder Kabir Uddin Ahmed Björn Olsen Mohammad Abul Kashem 《Veterinary microbiology》2014
Antibiotic resistance and ESBL constitute a risk to human and animal health. Birds residing close to humans could mirror the spectrum of human associated antibiotic resistance. Household pigeons were screened in Bangladesh to shed light on human associated, as well as, environmental antibiotic resistance. Escherichia coli from pigeons (n = 150) were tested against 11 antibiotics. 89% E. coli isolates were resistant to one or more critically important human antibiotics like ampicillin, cefadroxil, mecillinam, ciprofloxacin, gentamicin and tigecycline. No carbapenamase-producers were detected and the lower ESBL prevalence (5%) in pigeons. ESBL-producing E. coli isolates had blaCTX-M-15 genes. Pigeons shared some bacterial clones and had bird associated sequence types like E. coli ST1408. Fecal carriage of bacteria resistance of critically important human antibiotics, together with examples of shared genotypes among pigeons, indicate the human-birds and bird to bird transmissions are important in the epidemiology of antibiotic resistance. 相似文献
157.
This paper presents empirical evidence on the impact of socio-economic factors on the adoption of agroforestry practices in
Cameroon. The analysis uses primary farm-level data collected from June to December 1996. Three major provinces of the country
were covered, namely Centre, Southwest and Northwest Several agroforestry technologies have been promoted among farmers in
the zone, including alley farming, improved fallow, live fencing, cut-and-carry fodder and apiculture. The status of adoption
of each agroforestry practice is described and factors that affect adoption identified. These are gender of farmer, household
family size, level of education, farmer’s experience, membership within farmers’ associations, contact with research and extension,
security of land tenure, agroecological zone, distance of the village from nearest town, village accessibility and income
from livestock. Research findings indicate that since factors affecting farmers’ adoption of agroforestry practices differ
across techniques, generalisation is to be avoided. 相似文献
158.
Detailed chemical studies and RAPD analysis were done in different populations of Podophyllum hexandrum collected from high altitude regions of North Western Himalayas. Random amplified polymorphic DNA (RAPD) analysis revealed a high degree of genetic diversity among the 12 collected accessions, attributed to their geographical and climatic conditions. HPLC analysis also revealed variation in the concentration of two major marker compounds which lead to the identification of a chemotype. The study demonstrated that RAPD and chemical markers are very useful tools to compare the genetic relationship and pattern of variation among such prioritized and endangered medicinal plants. 相似文献
159.
Anne Ganteaume Mercedes Guijarro Marielle Jappiot Carmen Hernando Corinne Lampin-Maillet Pedro Pérez-Gorostiaga José A. Vega 《Annals of Forest Science》2011,68(3):531-541
• Introduction
Wildfires are considered the most important disturbance in the Mediterranean Basin, and some are propagated over long distances due to lift-off and ignition of firebrands. 相似文献160.
In Japan, ammoniacal copper quaternary wood preservatives type-1 (ACQ-1), which contains copper and benzalkonium chloride
as its active ingredients, is among the most widely used wood preservatives in the pressure treatment of wood. Benzalkonium
chloride (BAC) in commercial ACQ-1 products mainly comprises C12 and C14 homologues. In the present study, the leaching characteristics
of these BAC homologues were investigated using the heartwood and sapwood portions of Japanese cedar, Japanese larch, and
Sakhalin fir treated with ACQ-1 and 1% monoethanolamine (MEA) solution containing equimolar amounts of homologues. Distilled
water (DW) and artificial seawater (SW) were used as leaching media. Consequently, it was observed that the leaching rate
of the C12 homologue tended to be higher than that of the C14 homologue in DW. The leaching of C12 homologues was accelerated
by using SW, resulting in a significantly higher leaching rate than the C14 homologue using SW. It was thought that the difference
in the hydrophobicities based on alkyl chain lengths resulted in these phenomena. However, when the heartwood portion of Japanese
larch was treated with the homologues in MEA, the leaching rate of the C14 homologue was significantly higher than that of
the C12 homologue. 相似文献