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161.
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   
162.
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   
163.
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   
164.
Bacillus coagulans GBI-30, 6086 is a commercially available spore-forming non-toxigenic microorganism approved for use in dog foods with high resiliency to stresses associated with commercial manufacturing. The objectives of this research were to examine the effect of B. coagulans on stool quality, nutrient digestibility, and intestinal health markers in healthy adult dogs. Extruded diets containing graded levels of B. coagulans applied either to the base ration before extrusion or to the exterior of the kibble as a topical coating after extrusion were randomly assigned to 10 individually housed adult beagle dogs (7 castrated males and 3 spayed females) of similar age (5.75 ± 0.23 yr) and body weight (12.3 ± 1.5 kg). The study was designed as a 5 × 5 replicated Latin square with 16-d adaptation followed by 5-d total fecal collection for each period. Five dietary treatments were formulated to deliver a dose of 0-, 6-, 7-, 8-, and 9-log10 colony-forming units (CFU) per dog per day for the control (CON), extruded B. coagulans (PEX), and low, moderate, and high B. coagulans coating levels (PCL, PCM, and PCH), respectively. Food-grade TiO2 was added to all diets at a level of 0.4% to serve as an indigestible dietary marker for digestibility calculations. Data were analyzed using a mixed model through SAS (version 9.4, SAS Institute, Inc., Cary, NC) with treatment as a fixed effect and room (i.e., replicate), period, and dog(room) as random effects. Apparent total tract digestibility of organic matter, crude protein, crude fat, and gross energy calculated by the marker method were numerically greatest for dogs fed the 9-log10 dose treatment with increases (P < 0.05) observed in gross energy and organic matter digestibility compared with the negative control. No significant differences were observed in food intake, stool quality, fecal pH, fecal ammonia, fecal short-chain fatty acids, or branched-chain fatty acids for the extruded B. coagulans treatment (PEX) or the coated B. coagulans treatments (PCL, PCM, and PCH) compared with CON. These results suggest that B. coagulans has a favorable impact on nutrient digestibility and no apparent adverse effects when added to extruded diets at a daily intake level of up to 9-log10 CFU in healthy adult dogs.  相似文献   
165.

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   
166.
A 4-year-old castrated male mixed-breed dog with a history of coccidioidomycosis was referred for evaluation of abdominal and pleural effusion. Results of radiography, ultrasonography, cytologic evaluation of thoracic fluid, and serologic testing supported a diagnosis of constrictive pericarditis secondary to infection with Coccidioides immitis. Aggressive treatment for presumptive coccidioidomycosis was begun, but the dog's condition continued to deteriorate, and the dog was euthanatized. At necropsy, the pericardium was thicker than normal and fibrotic and adhered to the epicardium. Microscopically, the pericardium and 1 section of epicardium contained lymphoplasmacytic infiltrates with a few macrophages and neutrophils. Coccidioides immitis was cultured from pericardial fluid. A search of records from the Arizona Veterinary Diagnostic Laboratory for 1988 through 1998 revealed that of 46 dogs in which a diagnosis of coccidioidomycosis was confirmed at necropsy, 13 had involvement of the heart or pericardium.  相似文献   
167.
Precipitation samples were collected at Davis and Lake Tahoe, California, in 1972–73 and 1977–78 and analyzed for pH and major cations and anions. Rain and snow in this region of northern California are derived primarily from winter cyclonic storms which move easterly from the Pacific Ocean over Davis and then Lake Tahoe. Precipitation at both sites was found to be more acid than water in equilibrium with atmospheric CO2. Acidity at Lake Tahoe apparently increased over the 5-yr period of the study. Sulfate was the dominant acid anion in 1972–73 (not measured in 1977–78). A major source of sulfate in precipitation was probably industry in the San Francisco Bay Area, upwind of the study sites. Automobile exhaust emissions throughout the region, which contains three major interstate highways and several large urban centers, contribute both sulfate and nitrate precursors to the atmosphere. As in the Eastern United States, these strong acid anions are influencing precipitation chemistry in northern California, including the Sierra Nevada mountains.  相似文献   
168.
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   
169.

• 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   
170.
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   
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