Short-wave solar radiation level willingly tolerated by lactating Holstein cows in an equatorial semi-arid environment     

Steffan Edward Octávio Oliveira  Cíntia Carol de Melo Costa  João Batista Freire de Souza Jr  João Paulo Araújo Fernandes de Queiroz  Alex Sandro Campos Maia  Leonardo Lelis de Macedo Costa 《Tropical animal health and production》2014,46(8):1413-1417

The amount of short-wave solar radiation willingly tolerated by lactating Holstein cows on pasture was determined in an equatorial semi-arid environment. The study was carried out on a dairy farm located in Limoeiro do Norte, CE, northeastern Brazil. The observed behaviours were as follows: grazing, under the sun, under the shade, standing, lying, ruminating, idling and wallowing in the water. The behaviours were recorded using instantaneous scan sampling at regular intervals of 15 min from 0600 to 1800 hours over 5 days. On all sampling days, the meteorological variables, including local short-wave solar radiation (R _S-W, W m^?2), were recorded. The R _S-W data were divided into five levels. The sun exposure was more frequent under low (100 %) and moderately low (97 %) levels, when R _S-W remained below 500 W m^?2. The grazing was more intense under low (100 %) and moderately low (93 %) levels. Above 500 W m^?2, the grazing time significantly decreased (11 %). The cows avoided grazing under high (0 %) and very high (0 %) levels, when R _S-W exceeded 700 W m^?2. The ruminating behaviour was more frequent under high (33 %) and very high (37 %) levels, in which the highest averages of R _S-W were recorded (815 and 958 W m^?2, respectively). The standing posture was more frequent under low (100 %) and moderately low (97 %) levels. Therefore, the critical R _S-W level that motivates cows to stop grazing and seek shade was in the interval between 500 and 700 W m^?2.  相似文献   

Effects of road transportation or droving on the weight and metabolism of young bulls   总被引：1，自引：0，他引：1  

Marcella Cândia D’Oliveira  Maria Inês Lenz Souza  Ruy Alberto Caetano Corrêa Filho  Maria da Graça Morais  Camila Celeste Brandão Ferreira Ítavo  Gumercindo Loriano Franco 《Tropical animal health and production》2014,46(8):1447-1453

This study evaluated the effects of the mode of transportation on weight and metabolism of young bulls, which are generally transported by two systems: droving and truck. This experiment consisted of two phases: transportation and refeeding and involved transportation by droving and truck. Fifty young Nellore bulls were separated in equal numbers in both groups, droving group and truck group. In the transportation phase, animals were moved, in a 640-km journey. The refeeding phase consisted of 84 days and commenced after the animals arrived at the fattening farm. The effect of the transportation system on animals’ weight, metabolic hormones, and serum biochemistry was assessed after 28, 56, and 84 days. During the transportation phase, animals in the droving group lost 10.11 kg and animals in the truck group gained 13.1 kg. The truck group showed 20.5 kg of weight gain at the end of the refeeding phase. The highest triiodothyronine (T₃) and thyroxine (T₄) concentrations were observed on days 0 and 60 in the transportation phase in both droving and truck groups. The serum cortisol concentration was higher in the droving group than in the truck group on day 56 of the refeeding phase. The IGF-I concentrations were higher during the refeeding phase in the droving group than in the truck group. Our results showed that transportation by droving leads to increased weight loss and reduced further weight gain compared to transportation by truck and that serum concentrations of T₄, cortisol, and insulin-like growth factor (IGF-I) hormones are altered by the transportation system.  相似文献   

Evaluation of hepatitis E virus infection between different production systems of pigs in Brazil     

Marconni Victor da Costa Lana  Noemi Rovaris Gardinali  Raquel Aparecida Sales da Cruz  Letícya Lerner Lopes  Gustavo Sousa Silva  João Garcia Caramori Júnior  Anderson Castro Soares de Oliveira  Marcos de Almeida Souza  Edson Moleta Colodel  Amauri Alcindo Alfieri  Caroline Argenta Pescador 《Tropical animal health and production》2014,46(2):399-404

The objectives of this study were to (1) investigate the occurrence of hepatitis E virus (HEV) in pigs from large-scale and family-scale farms, (2) genetically characterize the strains isolated, and (3) study the pathogenesis of swine HEV infection via immunohistochemistry. A total of 50 pigs from 10 farms in Mato Grosso State, Brazil were divided according to type of production system into either large-scale farms (n?=?5) or family-scale farms (n?=?5). Samples of liver, gallbladder, small and large intestines, bile, and feces from the pigs were analyzed by nested PCR with primers targeting the ORF2 region of HEV and by immunohistochemistry. Of the eight HEV-positive samples from pigs of family-scale farms, phylogenetic analysis revealed that seven of the swine HEV isolates clustered with subtype 3b of genotype 3 and one isolate was categorized with subtype 3 f. The HEV antigen was detected mainly in the small intestine samples from family-scale farms, suggesting an early stage HEV infection. HEV was not detected in the samples of pigs from large-scale farms, reinforcing the need for additional studies to evaluate the risk of transmission of HEV to humans from pigs from family-scale farms in Mato Grosso State.  相似文献   

Evaluation of the effectiveness of Duddingtonia flagrans and Monacrosporium thaumasium in the biological control of gastrointestinal nematodes in female bovines bred in the semiarid region     

Manoel Eduardo da Silva  Fabio Ribeiro Braga  Luana Alcântara Borges  Jair Mendes de Oliveira  Walter dos Santos Lima  Marcos Pezzi Guimarães  Jackson Victor de Araújo 《Veterinary research communications》2014,38(2):101-106

Brazil has a herd of 212 million cattle and 171 million hectares of pastures that produce approximately 96 % of Brazilian beef. The Brazilian production system enables animal infection by endoparasites, which are considered one of the main obstacles for the development of this industry and are responsible for considerable economic losses. The control of parasitic diseases is performed via the administration of antiparasitic drugs, but they leave residues of the products in the treated animal, affect non-target organisms and select resistant strains of the parasites. The species D. flagrans and M. thaumasium are promising and sustainable alternatives for controlling gastrointestinal helminths of ruminants and other herbivores. In this study, we evaluated the efficacy of isolates of these species, formulated in a sodium alginate matrix and administered twice a week, to reduce the number of environmental infective larvae of gastrointestinal nematodes that affect prepubescent zebu females. The treated animals presented fewer eggs and a lower number of infective larvae per gram of faeces (p?<?0.05). The pastures occupied by treated animals showed a statistically significant reduction (p?<?0.05) of the number of L₃ and, furthermore, the genera Cooperia sp., Haemonchus sp., and Oesophagostomum sp. were the most prevalent. The average weight of the animals did not differ statistically (p?>?0.05) among the treated and control groups. The use of sodium alginate pellets as vehicle for delivery of the fungus mycelia D. flagrans (isolate AC001) and M. thaumasium (isolate NF34A) proved effective in controlling trichostrongylids in prepubescent cows bred in the semi-arid region, with an effective reduction in the number of infective larvae in the pastures.  相似文献   

Molecular characterization of canine coronavirus strains circulating in Brazil   总被引：1，自引：0，他引：1  

Erika Moutinho Costa  Tatiana Xavier de CastroFernanda de Oliveira Bottino  Rita de Cássia Nasser Cubel Garcia 《Veterinary microbiology》2014

To characterize canine coronavirus (CCoV) circulating in diarrheic puppies in Brazil, 250 fecal samples collected between 2006 and 2012 were tested. By using RT-PCR to partially amplify the M gene, CCoV RNA was detected in 30 samples. Sequence analysis of the M protein grouped eight strains with CCoV-I and another 19 with CCoV-II prototypes. To genotype/subtype the CCoV strains and assess the occurrence of single or multiple CCoV infections, RT-PCR of the S gene was performed, and 25/30 CCoV-positive strains amplified with one or two primer pairs. For 17/25 samples, single infections were detected as follows: six CCoV-I, nine CCoV-IIa and two CCoV-IIb. Eight samples were positive for more than one genotype/subtype as follows: seven CCoV-I/IIa and one CCoV-I/IIb. Sequence analysis revealed that the CCoV-I and IIa strains shared high genetic similarity to each other and to the prototypes. The Brazilian strains of CCoV-IIb displayed an aminoacid insertion that was also described in CCoV-IIb-UCD-1 and TGEV strains. Among the 25 CCoV-positive puppies, five had a fatal outcome, all but one of which were cases of mixed infection. The current study is the first reported molecular characterization of CCoV-I, IIa and IIb strains in Brazil.  相似文献   

Epidemiological Analysis of Leptospira spp. Infection in Equids from the Brejo Paraibano Microregion of Brazil     

Ruy B. de Oliveira Filho  Karla C. Malta  Júnior M.B. Oliveira  Vania L. Assis Santana  Mabel H.V. Harrop  Danilo T. Stipp  José W. Pinheiro Júnior 《Journal of Equine Veterinary Science》2014

Leptospirosis is a zoonotic disease that occurs in humans and several animal species, including cattle, pigs, and horses, and it has a worldwide distribution. In equids, leptospirosis manifests through recurrent uveitis and abortion and other reproductive disorders. The objective of the present study was to investigate the epidemiological situation of Leptospira spp. infection in equids from the Brejo Paraibano microregion in the northeast of Brazil, that is, to assess the prevalence of and identify the major risk factors for infection. For this purpose, blood samples were taken from 257 equids (204 horses, 46 mules, and 7 donkeys), and a microscopic agglutination test (MAT) was used as serological analysis, with 24 serovars of Leptospira spp. as antigens. Antibodies were observed in 16.2% of horses, 13.0% of mules, and 28.6% of donkeys. Animals between the ages of 2.5 and 11 years had a risk of infection 0.4 times lower than those younger than 2.5 years old (odds ratio, 0.4; 95% confidence interval, 0.18-0.90). Further studies are needed to identify potential wild reservoirs and the main routes of infections.  相似文献   

Faecal nitrogen excretion as an approach to estimate forage intake of wethers     

G. V. Kozloski  L. Oliveira  C. H. E. C. Poli  E. B. Azevedo  D. B. David  H. M. N. Ribeiro Filho  S. G. Collet 《Journal of animal physiology and animal nutrition》2014,98(4):659-666

Data from twenty‐two digestibility trials were compiled to examine the relationship between faecal N concentration and organic matter (OM) digestibility (OMD), and between faecal N excretion and OM intake (OMI) by wethers fed tropical or temperate forages alone or with supplements. Data set was grouped by diet type as follows: only tropical grass (n = 204), only temperate grass (n = 160), tropical grass plus supplement (n = 216), temperate grass plus supplement (n = 48), tropical grass plus tropical legume (n = 60) and temperate grass with ruminal infusion of tannins (n = 16). Positive correlation between OMD and either total faecal N concentration (Nfc, % of OM) or metabolic faecal N concentration (Nmetfc, % of OM) was significant for most diet types. Exceptions were the diet that included a tropical legume, where both relationships were negative, and the diet that included tannin extract, where the correlation between OMD and Nfc was not significant. Pearson correlation and linear regressions between OM intake (OMI, g/day) and faecal N excretion (Nf, g/day) were significant for all diet types. When OMI was estimated from the OM faecal excretion and Nfc‐based OMD values, the linear comparison between observed and estimated OMI values showed intercept different from 0 and slope different from 1. When OMI was estimated using the Nf‐based linear regressions, the linear comparison between observed and estimated OMI values showed neither intercept different from 0 nor slope different from 1. Both linear comparisons showed similar R² values (i.e. 0.78 vs. 0.79). In conclusion, linear equations are suitable for directly estimating OM intake by wethers, fed only forage or forage plus supplements, from the amount of N excreted in faeces. The use of this approach in experiments with grazing wethers has the advantage of accounting for individual variations in diet selection and digestion processes and precludes the use of techniques to estimate forage digestibility.  相似文献   

Circumferential variation of heartwood and stem quality in maritime pine stems     

Sofia Knapic  Vanda Oliveira  Marika Makkonen  Isabel Pinto-Seppä  Helena Pereira 《European Journal of Forest Research》2014,133(6):1007-1014

Maritime pine (Pinus pinaster Ait.) is an important timber and pulpwood species covering about 4 million ha in Portugal, Spain and France. This work studied the cross-sectional distribution of heartwood and sapwood along the stem using 3D modelling on 20 trees. The target was to assess the potential of this species for the industrial production of heartwood sawn products. The maritime pine stems were characterized by wide sapwood of 10 cm, in average, and the presence of heartwood at all height levels with constant diameter up to 35 % tree height, decreasing afterwards. In the radial section, the heartwood follows a circumferential-like shape which changes along the stem. Pith eccentricity index values were low and homogeneous regarding to stem and higher for heartwood. Heartwood cross-sectional shape was constant up to 45 % of total height of the tree and more elongated upwards. The constant heartwood diameter, low taper and pith eccentricity index, and an approximate circular shape up to 10 m height indicated these species’ potential to produce solid wood products made out of heartwood.  相似文献   

Nutrients and primary production along the eastern Aleutian Island Archipelago     

CALVIN W. MORDY  PHYLLIS J. STABENO  CAROL LADD  STEPHAN ZEEMAN  DAVID P. WISEGARVER  SIGRID A. SALO  GEORGE L. HUNT  JR 《Fisheries Oceanography》2005,14(S1):55-76

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Introduction to processes controlling variability in productivity and ecosystem structure of the Aleutian Archipelago     

PHYLLIS J. STABENO  GEORGE L. HUNT  JR  S. ALLEN MACKLIN 《Fisheries Oceanography》2005,14(S1):1-2

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