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11.
Spinosad‐mediated effects on the walking ability,midgut, and Malpighian tubules of Africanized honey bee workers 下载免费PDF全文
12.
Leilson Rocha Bezerra Severino Gonzaga Neto Ariosvaldo Nunes de Medeiros Tobyas Maia de Albuquerque Mariz Ronaldo Lopes Oliveira Ebson Pereira Cândido Aderbal Marcos de Azevedo Silva 《Tropical animal health and production》2013,45(5):1161-1169
In the present study, the effect of restricting the feed intake for 77 days and subsequent compensatory growth for 50 days of Sindi females were evaluated. Eighteen animals with an initial age of 21 months and a mean weight of 211.7 kg were placed into three groups according to the following alimentary regimens: feed ad libitum, feed restricted to 20 % dry matter, and feed restricted to 40 % dry matter. In the feed-restriction phase, the nutrient intake decreased (P?<?0.001) with an increase in the restriction level. As a consequence, the observed decrease in ingestion and serum concentrations of total protein, albumin and globulin, urea, glucose, calcium, and phosphorus were inversely proportional (P?<?0.001) to the restriction level. Significant differences in the nutrient intake and serum concentration were not observed in the realimentation phase (P?<?0.05). When animals in the control group reached the end of the feed-restriction phase, their weights (P?<?0.05) were similar to those in the 20 % restricted group, and both obtained a final weight that was greater than that of animals in the 40 % restricted group. In the feed-restriction phase, the control group had a similar mean daily weight gain (P?>?0.05) to animals in the 20 % restricted group and (P?<?0.05) 40 % restricted group. However, in the realimentation phase, the 40 % restricted group obtained greater weight gain rates (P?<?0.05), better food conversions, and partial compensatory gains. In particular, none of the restricted groups reached the final weight of the control group. In the feed-restriction phase, ingested nitrogen, nitrogen excreted in urine and feces, nitrogen balance and retained nitrogen decreased (P?<?0.05) with an increase in the restriction level. In the realimentation phase, none of the nitrogen balance variables were influenced by the restriction level (P?<?0.05). Females in the 40 % restricted group presented better food conversion rates and greater weight gains in the realimentation phase. Based on the animals’ compensatory weight gain, a feed-restriction rate of 20 and 40 % can be adopted as a nutritional management practice for prepubescent Sindi females. 相似文献
13.
14.
Almundena Bayo-Canha Luciana Delgado-Benarroch Julia Weiss Marcos Egea-Cortines 《Scientia Horticulturae》2007
We have studied the effect of artificial modification of leaf area on inflorescence and floral quality in Antirrhinum majus. We used two treatments where we clipped all the leaves except the first three pairs of true leaves, or we cut every leaf visible by the time the plant had six leaf pairs. Decreased leaf area caused a decrease in stem elongation that could be traced back to a decrease in internode elongation. Leaves left on the plant increased their size beyond control. Inflorescence quality was strongly affected since total floral number showed a strong decrease with reduced leaf area. In contrast, floral size hardly changed. Breeding programs in Antirrhinum should take into account growth conditions affecting leaf area when searching for changes in inflorescence quality while floral size can be screened independently of this factor. 相似文献
15.
Jos Diomedes Barbosa Carlos Magno C. de Oliveira Marcos Dutra Duarte Gabriela Riet-Correa Paulo Vargas Peixoto Carlos Hubinger Tokarnia 《Journal of Equine Veterinary Science》2006,26(9):393-398
The clinical and pathological aspects of a neurological disease observed in 16 horses in Pará, Amazonia, Brazil, are presented. The symptoms were mainly motor incoordination, paresis of the tongue, somnolence, difficulties in apprehension, chewing and swallowing of food, as well as instability and standing with abducted members. The clinical course was subacute or chronic and in most cases was not fatal. Postmortem examination performed in one already very sick, euthanized animal, did not show significant macroscopic lesions; histopathological examination revealed slight edema and degenerative alterations of a few axons, mainly in the medulla oblongata. In all pastures where horses were affected, plenty of bamboo had been eaten, probably because of scarcity of pasture. By feeding large amounts of fresh bamboo leaves of this region, in different growing stages, to three horses (horse 1, 47 g/kg/d for 30 days; horse 2, 10 g/kg/d for 60 days; horse 3, 18 g/kg on the first day, and 31 g/kg/d for 6 more days)—the animals ate the leaves unassisted—it was possible to reproduce nervous symptoms essentially identical to those observed in the natural disease 24 to 72 hours after the first feeding of the plant. In spite of continuous administration of the plant, intensity of the clinical signs did not increase. Based on field observations and comparison of the clinical and pathological pictures seen in the natural and experimental disease, the described illness can be concluded to be caused by the ingestion of large amounts of the leaves of Bambusa vulgaris f. vulgaris. 相似文献
16.
de Moura MQ Jeske S Gallina T Borsuk S Berne ME Villela MM 《Veterinary parasitology》2012,184(2-4):359-361
Public parks, especially in developing countries, are places where stray animals run free and may contaminate the environment with different species of parasites. In an evaluation of environmental sanitation of these sites, soil samples were collected monthly from public parks in the Pelotas city, Rio Grande do Sul State, Southern Brazil. Eggs of the nematode Lagochilascaris sp. were found in a public playground. This is the first report of identification of this nematode in Southern Brazil. 相似文献
17.
GROSS AND HISTOPATHOLOGIC CORRELATION OF LOW‐FIELD MAGNETIC RESONANCE IMAGING FINDINGS IN THE STIFLE OF ASYMPTOMATIC HORSES 下载免费PDF全文
Marcos P. Santos Santiago D. Gutierrez‐Nibeyro Alexia L. McKnight Kuldeep Singh 《Veterinary radiology & ultrasound》2015,56(4):407-416
With the recent introduction of a 0.25T rotating MRI system, clinical evaluation of the equine stifle joint is now possible in the average equine athlete. A recent publication described common abnormalities of horses with stifle lameness detected with a low‐field MRI system; however, postmortem corroboration of the lesions detected was not possible. Therefore, our objective was to compare postmortem findings with low‐field MRI findings in equine cadaver stifle joints. Ten fresh cadaver stifle joints from horses without clinical signs of stifle disease were evaluated using low‐field MRI, gross dissection, and histopathology. In eight stifles, either the lateral or medial cranial meniscotibial ligament had an irregular shape, fiber separation, or moderate abnormal signal intensity (SI) on all sequences. In five stifles, the medial femoral condyle had articular cartilage fibrillation with or without an osteochondral defect over the weight bearing surface of the medial femoral condyle. All stifles had abnormal SI on all sequences within the patellar ligaments that corresponded with adipose tissue infiltrating between the collagen bundles. Other abnormalities identified included articular cartilage fibrillation of the tibial condyles in three stifles, and articular cartilage fibrillation with chondral defects in the patella in three stifles. All abnormalities detected with low‐field MRI were corroborated by gross dissection. Findings from the current study supported the use of low‐field MRI for detection of stifle joint lesions in horses and demonstrated that some stifle joint pathologies may be subclinical in horses. 相似文献
18.
Heritability and genetic correlations between rumination time and production traits in Holstein dairy cows during different lactation phases 下载免费PDF全文
Riccardo Moretti Marcos Paulo Gonçalves de Rezende Stefano Biffani Riccardo Bozzi 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2018,135(4):293-299
So far, rumination has been used as a proxy for monitoring dairy cow health at farm level. However, investigating its genetic aspects as well as its correlation with other important productive traits may turn this management tool into a new informative selection criterion. However, scientific evidences on genetic correlation among rumination time (RT) and milk production and milk composition are still scarce. Therefore, the objective of this study was to estimate the heritability of RT across three lactation phases and its genetic correlation with milk production, milk composition and somatic cell count (SCC). Results of our study showed that heritability for RT was 0.34 and was constant across lactation. The mean genetic correlations between RT and milk production and composition traits were 0.07 (milk production), ?0.07 (protein yield), ?0.31 (fat yield), and ?0.32 (fat/protein ratio). The mean genetic correlation between RT and the SCC was 0.05. 相似文献
19.
Sousa Larissa Nascimento Batista Samira Pereira Silva Samara Santos da Silva Rômulo Fylipe Sarmento Wlysse Ferreira Mota Rinaldo Aparecido Brasil Arthur Willian Lima Amaku Marcos Feitosa Thais Ferreira Vilela Vinícius Longo Ribeiro 《Veterinary research communications》2022,46(2):507-515
Veterinary Research Communications - This study aimed to describe the transmission of T. gondii in naturally infected goats in the semiarid region of northeastern Brazil, through evaluating the... 相似文献
20.
Phosphine resistance, respiration rate and fitness consequences in stored-product insects 总被引:5,自引:0,他引:5
Resistance to fumigants has been frequently reported in insect pests of stored products and is one of the obstacles in controlling these pests. The authors studied phosphine resistance and its physiological basis in adult insects of 12 populations of Tribolium castaneum (Herbst) (Tenebrionidae), ten populations of Rhyzopertha dominica (F.) (Bostrichidae) and eight populations of Oryzaephilus surinamensis L. (Silvanidae) from Brazil, and the possible existence of fitness costs associated with phosphine resistance in the absence of this fumigant. The bioassays for the detection of phosphine resistance followed the FAO standard method. The production of carbon dioxide and the instantaneous rate of population increase (r(i)) of each population of each species were correlated with their resistance ratios at the LC(50). The resistance ratio at LC(50) in T. castaneum ranged from 1.0- to 186.2-fold, in R. dominica from 2.0- to 71.0-fold and in O. surinamensis from 1.9- to 32.2-fold. Ten populations of T. castaneum, nine populations of R. dominica and seven populations of O. surinamensis were resistant to phosphine. In all three species there was significant association (P < 0.05) between respiration rate and phosphine resistance. The populations with lower carbon dioxide production showed a higher resistance ratio, suggesting that the lower respiration rate is the physiological basis of phosphine resistance by reducing the fumigant uptake in the resistant insects. Conversely, populations with higher r(i) showed lower resistance ratios, which could indicate a lower rate of reproduction of the resistant populations compared with susceptible populations. Thus, management strategies based on the interruption of phosphine fumigation may result in reestablishment of susceptibility, and shows good potential for more effective management of phosphine-resistant populations. 相似文献