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81.
Effect of Stocking Density on Growth,Survival, and Condition of the Mexican Cichlid Cichlasoma beani
Edgar A. Aragon‐Flores Edna F. Valdez‐Hernandez Leonardo Martinez‐Cardenas Maria R. Castaeda‐Chavez Alfonso A. Gonzales‐Diaz Miriam Soria‐Barreto Javier M. J. Ruiz‐Velazco Emilio Pea‐Messina 《Journal of the World Aquaculture Society》2014,45(4):447-453
The Mexican cichlid Cichlasoma beani is currently exploited regionally as food and can be commercialized in the aquarium trade. Natural populations of C. beani may already be negatively affected by anthropogenic alteration of the areas in which it is distributed. The aim of the present study was to examine the effect on growth, survival, and condition of C. beani cultured in three stocking densities: three (D3), six (D6), and nine (D9) fish per each 40 L tank. At the end of a 6‐wk trial the fish cultured in D3 were longer, heavier, and grew faster than the rest of the treatments but their survival was the lowest compared to D6 and D9. The mortalities were caused by a strong aggressive behavior in D3. 相似文献
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83.
Nicols Javier Litterio Augusto Matías Lorenzutti María del Pilar Zarazaga Martín Alejandro Himelfarb Manuel Ignacio San Andrs‐Larrea Juan Manuel Serrano‐Rodríguez 《Journal of veterinary pharmacology and therapeutics》2021,44(1):68-78
Cefquinome is a fourth‐generation cephalosporin that is used empirically in goats. Different physiologic factors like pregnancy or lactation could determine the pharmacokinetic behavior of drugs in the organism. The objectives of this study are to (a) compare the pharmacokinetics of cefquinome after intravenous and intramuscular administration in adult nonpregnant (n = 6), pregnant (n = 6), and lactating goats (n = 6), at a dose of 2 mg/kg, with rich sampling by nonlinear mixed‐effects modeling, (b) conduct a pharmacokinetic/pharmacodynamic analysis to evaluate the efficacy of the recommended posology in goats with different physiological states, and (c) determine the optimal posology that achieve a PTA value ≥ 90%, taking into account a T > MIC ≥ 60% of a MIC value ≤ 0.25 µg/ml, in the different subpopulations of goats for both routes. Gestation significantly increased Ka and V1, while reduced F0, Cl, and Q. On the other hand, lactation significantly increased V1 and reduced Tk0. Cefquinome concentrations achieved in placental cotyledon, amniotic fluid, and fetal serum indicate a minimal penetration across the placental barrier. Moreover, milk penetration of cefquinome was minimal. The total body clearance of cefquinome for goats was 0.29 L kg?1 hr?1, that is apparently higher than the reported for cows (0.13 L kg?1 hr?1) and pigs (0.16 L kg?1 hr?1). So, the optimal dose regimen for cefquinome after intravenous and intramuscular administration required higher dose and frequency of administration compared with recommendations for cows or pigs. Therefore, 2 mg kg?1 8 hr?1 and 5 mg kg?1 12 hr?1 could be used for IV and IM routes, respectively, for the treatment of respiratory infections caused by P. multocida and M. haemolytica, but only 5 mg kg?1 12 hr?1 by both routes should be recommended for Escherichia coli infections. 相似文献
84.
İsmail Hakkı Nur William Pérez Horst Erich König 《Anatomia, histologia, embryologia》2021,50(3):658-667
This study aims to reveal the morphological properties of facial nerve and the middle ear in Van cats. Study material was composed of 6 female Van cats. Dissections were performed under a Zoom Stereo Microscope. There was no plexus buccalis in Van cats. The chorda tympani was observed to pass through an opening in the tympanic cavity, emerge through a small opening just behind the retroarticular process, and join the lingual nerve. A rounded anatomical formation with a size of 2.75 ± 0.3 mm was found to be located within the mastoid process of the temporal bone between the facial nerve and the auricular branch of the vagus nerve. The stapes nerve was not present. The geniculate ganglion was very prominent and about 1.00 mm high. The deep petrosal nerve was observed to emerge from the plexus tympanicus. The bulla tympanica was 18.96 ± 0.10 mm long, 13.03 ± 0.20 mm wide and 13.16 ± 0.20 mm high. After leaving the mandibular nerve, the n.tensoris tympani coursed caudally around the a.maxillaris, formed an ansa, entered the tympanic cavity through the canalis musculotubarius and reached an end in the m. tensor tympani. Due to the scarcity of studies on the middle ears of Van cats, it is thought that this study will fill a gap in the field of veterinary anatomy. 相似文献
85.
86.
Ana Carina Heil da Silva Matos Angélica Consalter Bárbara Paula dos Santos Batista Ana Beatriz Monteiro Fonseca Ana Maria Reis Ferreira Juliana da Silva Leite 《Reproduction in domestic animals》2021,56(4):667-672
Granulosa cell tumour, an ovarian neoplasm of stromal origin, is an important tumour related to oestrogenic dominance syndrome and cystic endometrial hyperplasia–pyometra complex. In order to analyse ovarian tumour´s malignant potential, immunohistochemical markers can be used, such as anti-HER2 and anti-Ki-67. The aim of this study was to evaluate the expression of immunohistochemical markers HER-2 and Ki-67 in granulosa cell tumour from bitches´ ovaries. In HER-2 immunomarker analysis using the HercepTest® method, most tumours were classified as 2+ (moderate labelling). Concerning Ki-67 immunomarker, only one case was described as having a high proliferative index. An association was found between immunostained cell percentage by anti-HER-2 antibodies and high pleomorphism, represented by the pattern of follicular/trabecular tumour arrangement. There was no correlation between anti-Ki-67 and anti-HER-2 antibody immunostaining intensities, probably due to only one case with a high Ki-67 index. With an effective protocol for HER-2 and Ki-67 immunohistochemical identification in granulosa cell tumours in bitches, it was possible to characterize this neoplasm proliferation profile. 相似文献
87.
Nils H. Flores Huarco Susana M. Giuliano Fernanda G. Fumuso Marcelo H. Miragaya Hernán C. Cucho Dolmos María I. Carretero 《Reproduction in domestic animals》2021,56(11):1387-1397
The objective of this study was to evaluate the effect of collagenase and two final dimethylformamide (DMF) concentrations (4% and 7%) on alpaca frozen-thawed sperm quality. A total of 25 ejaculates from 5 alpaca were obtained using electroejaculation. Each individual ejaculate was evaluated and then diluted 4:1 in a solution of 1 mg/ml collagenase in HEPES-TALP medium and incubated for 4 min at 37°C. Subsequently, samples were diluted in TRIS-fructose-citric acid-egg yolk and cooled to 5°C. Then, each sample was divided in two aliquots and DMF at final concentration of 4% or 7% was added, equilibrated for 1 hr at 5°C and frozen over liquid nitrogen vapours. A Kruskal–Wallis test was used to evaluate the sperm morphometry, and Completely Random Block designs were used to analyse sperm motility, viability, membrane function and acrosome status. After collagenase incubation, none of the samples showed thread formation, and sperm parameters were preserved. Non-progressive motile sperm were higher (p < .05) in equilibrated samples (4% DMF: 31.8 ± 8.3% and 7% DMF: 36.3 ± 11.8%) compared to raw (10.1 ± 4.3%) and frozen-thawed semen (4% DMF: 9.7 ± 1.8% and 7% DMF: 7.5 ± 3.2%). Sperm membrane function, membrane integrity and intact acrosomes were higher (p < .05) in raw semen (40.1 ± 12.2%, 94.6 ± 3.2% and 91.3 ± 8.1%) compared to frozen-thawed samples (4% DMF: 19.8 ± 4.7%, 53.2 ± 2.7%, 65.7 ± 8.7% and 7% DMF: 20.4 ± 4.5%, 54.1 ± 1.4%, 64.6 ± 9.1%). Length of the sperm head was lower in frozen-thawed samples, being statistically different with 4% DMF compared to pre-freezing samples. The ratio between acrosome and head areas was greater (p < .05) in frozen-thawed samples. Incubation of raw alpaca semen with collagenase decreased the thread formation without affecting sperm quality. Frozen of collagenase treated alpaca semen with 4% or 7% DMF did not preserve the sperm parameters in thawed samples. 相似文献
88.
89.
Pablo Parodi Luis G. Corbellini Vanessa B. Leotti Rodolfo Rivero Cecilia Miraballes Franklin Riet-Correa Jos M. Venzal María T. Armúa-Fernndez 《Journal of veterinary diagnostic investigation》2021,33(1):73
Detection of bovine Babesia spp. and Anaplasma marginale is based on the reading of Giemsa-stained blood or organ smears, which can have low sensitivity. Our aim was to improve the detection of bovine Babesia spp. and A. marginale by validating a multiplex PCR (mPCR). We used 466 samples of blood and/or organs of animals with signs and presumptive autopsy findings of babesiosis or anaplasmosis. The primers in our mPCR amplified the rap-1a gene region of Babesia bovis and B. bigemina, and the msp-5 region of A. marginale. We used a Bayesian model with a non-informative priori distribution for the prevalence estimate and informative priori distribution for estimation of sensitivity and specificity. The sensitivity and specificity for smear detection of Babesia spp. were 68.6% and 99.1%, and for A. marginale 85.6% and 98.8%, respectively. Sensitivity and specificity for mPCR detection for Babesia spp. were 94.2% and 97.1%, and for A. marginale 95.2% and 92.7%, respectively. Our mPCR had good accuracy in detecting Babesia spp. and A. marginale, and would be a reliable test for veterinarians to choose the correct treatment for each agent. 相似文献
90.
André Guimarães Maciel e Silva Suely Cristina Gomes de Lima Pedro Danilo de Oliveira Michel dos Santos Moraes Célia Maria Costa Guimarães Jamile Andréa Rodrigues da Silva Alexandre Rossetto Garcia Benjamim de Souza Nahúm Lilaine de Sousa Neres Gerlane Nunes Noronha José de Brito Lourenço Júnior 《Animal Science Journal》2021,92(1):e13576
The objective was to evaluate the effect of concentrate supplementation using by-products of the Amazonian industry on milk production, milk composition, and milk fatty acid profile of dairy buffaloes. Twelve lactating buffaloes (544.5 ± 35.6 kg, 6.4 ± 2.2 years old, 59 ± 6 days in milk) were allotted in a pasture of Mombaça grass and managed under rotational grazing (4 days occupancy/28 days rest). A 3 × 3 Latin square was adopted, and each animal alternately received three supplementary treatments based on corn bran + soybean meal or cupuaçu cake or murumuru cake for 21 days per treatment. Murumuru cake increased the levels of lauric acid and myristic acid in the milk (p < 0.05). Murumuru cake reduced the unsaturated fatty acid contents in the milk compared with animals fed control diet or cupuaçu cake (24.27% vs. 25.24% vs. 25.08%). The n-6/n-3 ratio was 2.6, 1.97, and 2.0 in the control, cupuaçu, and murumuru groups, respectively. Based on this parameter, cakes made from cupuaçu as well as murumuru could be considered to be adequate for inclusion in dairy water buffalo feed. However, the murumuru cake addition requires some caution because its use induces the secretion of higher levels of lauric and myristic fatty acids that are related to human cardiovascular disease. 相似文献