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11.
1. Under summer conditions in north Iraq, 2 000 chicks were reared for 56 d in two broiler houses. One house was provided with two air‐coolers. The birds were housed at densities of eight to 16 birds/m2.

2. Differences in weight gain between birds in cooled and uncooled houses ranged from 101.5 g at eight birds/m2 to 385 g at 16 birds/m2. Food consumption increased gradually with increasing bird density. Food conversion efficiency, meat yield and carcass conformation were much better in the cooled house than under conventional conditions.

3. The financial return/m2 ranged from 2.30 to 4.51 ID1 in the cooled house, compared with 2.01 to 2.77 ID in the uncooled house at different floor densities.  相似文献   

12.
1. Certain rapeseed meals in the diet of hens laying brown eggs result in the production, from some birds, of eggs which have a “ fishy ” or “ crabby ” odour because of the presence of trimethylamine.

2. Such susceptible birds have been used to demonstrate that the activity can be extracted from rapeseed meal with appropriate solvents.  相似文献   

13.
The aim of these experiments was to investigate the potential antiviral effect of Saccharomyces cerevisiaeβ‐glucan on the pneumonia induced by swine influenza virus (SIV). Forty colostrum‐deprived 5‐day‐old piglets were randomly divided into four groups of 10. The 20 pigs in groups 1 and 2 were administered Saccharomyces cerevisiaeβ‐glucan orally (50 mg/day/pig; En‐Bio Technology Co., Ltd) for 3 days before SIV infection and those in groups 3 and 4 were given culture medium/diluent alone. Groups 1 and 3 were inoculated intranasally with 3 ml of tissue culture fluid containing 2 × 106 tissue culture infective doses 50% (TCID50)/ml of SIV and those in groups 2 and 4 were exposed in the same manner to uninfected cell culture supernatant. The microscopic lung lesions induced by SIV infection (group 1 pigs) were significantly more severe than those induced by infection in animals pre‐administered β‐glucan (group 3) (P < 0.05). Significantly more SIV nucleic acid was detected in the lungs of pigs experimentally infected with SIV only (group 1) at 5, 7 and 10 days post‐inoculation (dpi) compared with lungs from pigs pre‐administered β‐glucan and infected with SIV (group 3) (P < 0.05). The concentrations of interferon‐γ (IFN‐γ) and nitric oxide (NO) in bronchoalveolar lavage fluid from pigs pre‐administered β‐glucan and infected with SIV (group 3) were significantly higher than for any other group at 7 and 10 dpi for IFN‐γ, and at 5, 7 and 10 dpi for NO (P < 0.05). Saccharomyces cerevisiaeβ‐glucan reduced the pulmonary lesion score and viral replication rate in SIV‐infected pigs. These findings support the potential application of β‐glucan as prophylactic/treatment agent in influenza virus infection.  相似文献   
14.
Tropical Animal Health and Production - The objective of this study was to compare hoof anatomy, hoof growth pattern, and hoof weight-bearing surface of six different Iranian sheep breeds to...  相似文献   
15.
Papillomaviruses are non-enveloped, DNA viruses that infect skin and mucosa of a wide variety of vertebrates, causing neoplasias or simply persisting asymptomatically. Avian papillomaviruses, with six fully sequenced genomes, are the second most studied group after mammalian papillomaviruses. In this study, we describe the first oral avian papillomavirus, detected in the tongue of a dead Yorkshire canary (Serinus canaria) and in oral swabs of the same bird and other two live canaries from an aviary in Madrid, Spain. Its genome is 8,071 bp and presents the canonical papillomavirus architecture with six early (E6, E7, E1, E9, E2, E4) and two late open reading frames (L1 and L2) and a long control region between L1 and E6. This new avian papillomavirus L1 gene shares a 64% pairwise identity with FcPV1 L1, so it has been classified as a new species (ScPV1) within the Ethapapillomavirus genus. Although the canary died after showing breathing problems, there is no evidence that the papillomavirus caused those symptoms so it could be part of the oral microbiota of the birds. Hence, future investigations are needed to evaluate the clinical relevance of the virus.  相似文献   
16.
This study was performed to determine pharmacokinetic profiles of the two active metabolites of the analgesic drug metamizole (dipyrone , MET), 4‐methylaminoantipyrine (MAA), and 4‐aminoantipyrine (AA), after intravenous (i.v., intramuscular (i.m.), and oral (p.o.) administration in cats. Six healthy mixed‐breed cats were administered MET (25 mg/kg) by i.v., i.m., or p.o. routes in a crossover design. Adverse clinical signs, namely salivation and vomiting, were detected in all groups (i.v. 67%, i.m. 34%, and p.o. 15%). The mean maximal plasma concentration of MAA for i.v., i.m., and p.o. administrations was 148.63 ± 106.64, 18.74 ± 4.97, and 20.59 ± 15.29 μg/ml, respectively, with about 7 hr of half‐life in all routes. Among the administration routes, the area under the plasma concentration curve (AUC) value was the lowest after i.m. administration and the AUCEV/i.v. ratio was higher in p.o. than the i.m. administration without statistical significance. The plasma concentration of AA was detectable up to 24 hr, and the mean plasma concentrations were smaller than MAA. The present results suggest that MET is converted into the active metabolites in cats as in humans. Further pharmacodynamics and safety studies should be performed before any clinical use.  相似文献   
17.
Seven types of fungal melanins were compared with humic compounds from chernozem and podzol soils and with commercial humic acid. The results indicate some similarities but also distinct differences between the melanins and humic substances in spectral characteristics in the UV and visible regions and in their resistance to thermal degradation.  相似文献   
18.
Ohne Zusammenfassung Mit 1 Abbildung.  相似文献   
19.
20.
A PCR-based method was developed for the identification and detection of Phytophthora capsici in pepper plants. Three PCR primers (CAPFW, CAPRV1 and CAPRV2) specific for P. capsiciwere designed based on the sequence of its internal transcribed spacer regions. CAPFW/CAPRV1 amplify a 452 bp product from P. capsici DNA whereas CAPFW/CAPRV2 a 595 bp fragment; neither set amplifies DNA from pepper or several fungi pathogenic to pepper. In conventional (single-round) PCR, the limit of detection was 5 pg DNA for both primer sets, whereas in nested PCR the detection limit for both was of 0.5 fg. However, when the dilution series of target DNA were spiked with plant DNA, amplification declined two-fold in both conventional and nested PCR. The CAPFW/CAPRV2 set in conventional PCR was used to detect P. capsici DNA in inoculated plants. Detection occurred as soon as 8h post-inoculation in stem samples from infected but still symptomless plants. The method was also tested to detect fungal DNA in infected soils.  相似文献   
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