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311.
312.
Di Fabio J Rossini LI Orbell SJ Paul G Huggins MB Malo A Silva BG Cook JK 《Avian diseases》2000,44(3):582-589
Fifteen isolations of infectious bronchitis (IB) virus were made from a total of 126 Brazilian poultry flocks of all ages that were examined. These flocks (14 chicken and 1 quail) were experiencing a variety of IB-like conditions including respiratory disease, digestive and kidney problems, and drops in egg production. One of the isolates was of the Massachusetts serotype. The remainder were examined by means of cross-neutralization tests in tracheal organ cultures and were shown to belong to at least four antigenic groups, all different from ones described previously in other countries. Some, but not all, of the flocks from which they were isolated had been vaccinated against IB with vaccines of the Massachusetts serotype. In vivo protection studies showed that the MA5 vaccine (of the Massachusetts serotype) protected well against challenge with four of these isolates, representing the different serotypes reported in this study. 相似文献
313.
Salvatore Mastrangelo Slim Ben Jemaa Gianluca Sottile Sara Casu Baldassare Portolano Elena Ciani Fabio Pilla 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(6):526-534
Selective breeding has led to modifications in the genome of many livestock breeds. In this study, we identified the genomic regions that may explain some of the phenotypic differences between two closely related breeds from Sardinia. A total of 44 animals, 20 Sardinian Ancestral Black (SAB) and 24 Sardinian White (SW), were genotyped using the Illumina Ovine 50K array. A total of 68, 38 and 15 significant markers were identified using the case–control genome‐wide association study (GWAS), the Bayesian population differentiation analysis (FST) and the Rsb metric, respectively. Comparisons among the approaches revealed a total of 22 overlapping markers between GWAS and FST and one marker between GWAS and Rsb. Three markers detected by Rsb were also located near (<2 Mb) to highly significant regions identified by GWAS and FST analyses. Moreover, one candidate marker identified by GWAS and FST approaches was located in a run of homozygosity island that was shared by both breeds. We identified several genes involved in many phenotypic differences (such as stature and growth, reproduction, ear size, coat colour, behaviour) between the two analysed breeds. This study shows that combining several genome‐wide approaches could improve discovery of regions involved in the variability of breeding traits and responsible for the phenotypic diversity even between closely related breeds. Overall, the combination of such genome‐wide methods can be extended to other livestock breeds that share between them a similar genetic background, to understand the process that shapes the patterns of genetic variability between closely related populations. 相似文献
314.
Giovanna Faria Moraes Luíza Rodrigues Alves Abreu Fabio Luiz Buranelo Toral Isabel Cristina Ferreira Henrique Torres Ventura Jos Aurlio Garcia Bergmann Idalmo Garcia Pereira 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(6):464-473
The objectives were to conduct a genetic evaluation of residual feed intake (RFI) and residual feed intake adjusted for fat (RFIFat) and to analyse the effect of selection for these traits on growth, carcass and reproductive traits. Data from 945 Nellore bulls in seven feed efficiency tests in a feedlot were analysed. Genetic evaluation was performed using an animal model in which the feed efficiency test and age of the animal at the beginning of the test were considered as a systematic effect. Direct additive genetic and residual effects were considered as random effects. Correlations and genetic gains were estimated by two‐trait analysis between feed efficiency measures (RFI and RFIFat) and other traits. Feed conversion showed low heritability (0.06), but dry matter intake (DMI), average daily gain, RFI, RFIFat, metabolic body weight and scrotal circumference measured at 450 days of age (SC450) showed moderate to high heritability (0.49, 0.28, 0.33, 0.36, 0.38 and 0.80, respectively). Similarly, ribeye area, backfat thickness, rump cap fat thickness, marbling score and subcutaneous fat thickness also had high heritability values (0.46, 0.37, 0.57, 0.51 and 0.47, respectively). Genetic correlations between RFI and SC450 were null, and between RFIFat and SC450 were strongly positive. Genetic and phenotypic correlations of RFI and RFIFat with carcass traits were not different from zero, as correlated responses for carcass traits were also not different from zero. The Nellore selection for feed efficiency by RFI or RFIFat allows the recognition of feed efficient animals, with DMI reduction and without significant changes in growth and carcass traits. However, because of the observed results between RFIFat and SC450, selection of animals should be analysed with caution and a preselection for reproductive traits is necessary to avoid reproductive impairments in the herd. 相似文献
315.
Fabio Leonardi Giovanna Lucrezia Costa Claudia Dina Interlandi Jessica Rosa Andrea Ghidelli Marcello Musicò 《Veterinary anaesthesia and analgesia》2019,46(1):79-83
Objective
To evaluate the anaesthetic effects of three different alfaxalone doses to induce anaesthesia in goldfish.Study design
Prospective, randomized, clinical study.Animals
Thirty goldfish undergoing skin scraping, gill examination and stool collection.Methods
Each fish was transferred to an individual 4 L induction tank and randomly allocated into one of three groups (n = 10), in which alfaxalone was administered at concentrations of 6, 7 or 9 mg L–1. The depth of anaesthesia was evaluated by approach reaction, equilibrium, opercular movement and reaction to tactile stimuli. Sedation, light anaesthesia, surgical anaesthesia and recovery times were recorded. Data were analyzed with analysis of variance. A p value <0.05 was considered significant.Results
Surgical anaesthesia was achieved in all fish. Goldfish induced with alfaxalone 7 and 9 mg L–1 showed a mild excitement phase. Time to sedation of the 6 mg L–1 dose (5.89 ± 0.40 minutes) was significantly longer compared to the 7 mg L–1 (3.97 ± 0.40 minutes) and 9 mg L–1 doses (3.94 ± 0.40 minutes). Times to light anaesthesia and surgical anaesthesia of the 9 mg L–1 dose (7.65 ± 1.04 and 9.60 ± 1.84 minutes, respectively) were significantly faster compared with those of the 6 mg L–1 dose (13.79 ± 1.04 and 19.75 ± 1.84 minutes, respectively) and the 7 mg L–1 dose (13.55 ± 1.04 and 21.24 ± 1.84 minutes, respectively). No significant differences were recorded in recovery time. Cessation of opercular movement was recorded in two fish induced with 7 mg L–1 and in two induced with 9 mg L–1. No mortality occurred.Conclusions
and clinical relevance Alfaxalone is a reliable agent for immersion anaesthesia in goldfish. Immersion in water containing 6 mg alfaxalone L–1 provided smooth induction of anaesthesia, and no obvious side effects were encountered. Higher doses shortened induction time and caused respiratory depression and excitatory movements. 相似文献316.
Daniele Della Santa Federica Rossi Fabio Carlucci Massimo Vignoli Patrick Kircher 《Veterinary radiology & ultrasound》2008,49(5):484-486
In dogs, surgical removal of plant awns causing a foreign body granuloma or abscess may be challenging. The inability to localize the foreign body during surgical removal often leads to abscess recurrence. In this report, we describe ultrasound-guided retrieval as an alternative to standard surgical retrieval in animals where the plant awn can be identified sonographically. This procedure was used in six dogs with a superficial abscess due to a plant awn, and in all dogs the foreign body was successfully retrieved with Hartmann forceps. No complication was observed and no abscess recurred. Minimally invasive ultrasound-guided plant awn retrieval appears to be a safe effective method of retrieving superficially located plant awns in the dog. 相似文献
317.
318.
319.
Fabio P. Gomes Marco A. Oliva Marcelo S. Mielke Alex-Alan F. Almeida Leonardo A. Aquino 《Scientia Horticulturae》2010
The role of drought-induced proline accumulation in coconut leaves is still unclear. With the objective of evaluating the impact of water shortage on leaf osmotic potential, proline accumulation and cell membrane stability in young plants of two Brazilian Green Dwarf coconut ecotypes from contrasting areas (Brazilian Green Dwarf from Una, Bahia, UGD, and from Jiqui, Rio Grande do Norte, JGD), a pot experiment was conducted under greenhouse conditions. Three drought cycles consisting of suspension of irrigation until the net photosynthetic rate (A) approached zero and rewatering until recovery of A to 85% of the irrigated control plants. Pre-dawn leaf water potential (ΨPD) reached −1.2 MPa at the point of maximum stress (PMS). Dry matter production and leaf area were severely reduced by drought treatment in the two ecotypes. Corrected values of osmotic potential were significantly reduced in stressed plants of the two ecotypes. Green dwarf coconut palm showed low osmotic adjustment (from 0.05 to 0.24 MPa) and significant accumulation of proline (from 1.5 to 2.1 times in relation to control) in leaflets in response to water deficit. Considering the growth reduction observed in both ecotypes, proline was not associated to osmoregulation. On the other hand, the absence of membrane damage, as indicated by electrolyte leakage method, suggests that the protective role of proline in this specie can be more important. The two ecotypes of Green dwarf coconut palm behaved similarly in the present experiment for most traits evaluated. Slight differences among the ecotypes were observed with respect to the response to treatments, such as higher proline accumulation in JGD. 相似文献
320.
Diego Moreira de Souza Sabrina Medeiros Suita Fabio Pereira Leivas Leite Luis Alberto Romano Wilson Wasielesky Eduardo Luis Cupertino Ballester 《Aquaculture Research》2012,43(12):1828-1837
The present work evaluated the use of probiotics during the nursery rearing of the pink shrimp Farfantepenaeus brasiliensis, in a zero exchange aerobic heterotrophic culture system during 30 days. Three replicate tanks were randomly assigned to the following treatments: (1) Bacillus spp. mixture (Sanolife Pro‐‐W®), (2) Bacillus sp., Enterococcus sp., Lactobacillus spp. mixture (Biomin Start‐grow®), (3) Bacillus cereus var. toyoi and (4) control treatment (without probiotic addition). Bacteriological analysis monitored the abundance of presumptive Vibrio spp. in the water of experimental tanks. For the immunological analysis, shrimp haemolymph was collected to determine the granular haemocyte count and total protein concentration. Results showed that mean final weight and specific growth rate of shrimp in the probiotic treatments were significantly higher. Furthermore, shrimp reared in the probiotic treatments showed higher levels of total protein and granular haemocyte. The bacteriological analysis showed that the concentration of Vibrio spp. measured in probiotic treatment tanks was lower than that recorded in the control tanks. 相似文献