"Benchmark" - a large observational study of Ontario beef breeding herds: Study design and collection of data          下载免费PDF全文

McDermott JJ  Alves DM  Anderson NG  Martin SW 《The Canadian veterinary journal. La revue veterinaire canadienne》1991,32(7):407-412

The methods used in a large field study which investigated the health and productivity of Ontario beef breeding herds are described. Beginning in the calving season of 1986, 180 breeding herds on 170 randomly sampled farms were followed for a two year period, using producer records and annual farm visits.

The response (cooperation) rate among the eligible producers initially contacted was 70%. Approximately two-thirds of producers maintained individual animal records, primarily calving season records. Approximately 40% recorded disease occurrences.

The advantages, disadvantages, and interpretation of “on-farm” observational studies are discussed.

  相似文献   

Cassava dreg as replacement of corn in goat kid diets     

Lucíola Vilarim Ferraz  Adriana Guim  Robson Magno Liberal Véras  Francisco Fernando Ramos de Carvalho  Marciela Thais Dino de Freitas 《Tropical animal health and production》2018,50(2):309-315

The effects of corn replacement by cassava dreg in diets of crossbred goat kids were evaluated. We tested the impacts of 0, 33, 66 and 100% replacement on intake, digestibility, feeding behaviour, performance and carcass characteristics. Thirty-six goat kids, aged between 4 and 5 months and with initial body weights of 17.61 ± 1.98 kg, were used in a completely randomised design. Analysis of regression revealed a negative linear effect on neutral detergent fibre (NDF) intake and a positive linear effect on non-fibrous carbohydrates (NFC) and hydrocyanic acids (HCN) intake. Cassava dreg use had a positive linear effect on organic matter digestibility and non-fibrous carbohydrates. Based on our results, cassava dreg use did not negatively impact animal performance, feeding behaviour and carcass characteristics, suggesting that it may replace corn up to 100% in the diets of confined goat kids.  相似文献   

Melatonin reduces apoptotic cells,SOD2 and HSPB1 and improves the in vitro production and quality of bovine blastocysts          下载免费PDF全文

TC Marques  EC da Silva Santos  TO Diesel  LO Leme  CF Martins  MAN Dode  BG Alves  FPH Costa  EB de Oliveira  ML Gambarini 《Reproduction in domestic animals》2018,53(1):226-236

Effects of adding different concentrations of melatonin (10^?7, 10^?9 and 10^?11 M) to maturation (Experiment 1; Control, IVM  + 10^?7, IVM  + 10^?9, IVM  + 10^?11) and culture media (Experiment 2; Control, IVC  + 10^?7, IVC  + 10^?9, IVC  + 10^?11) were evaluated on in vitro bovine embryonic development. The optimal concentration of melatonin (10^?9 M) from Experiments 1–2 was tested in both maturation and/or culture media of Experiment 3 (Control, IVM  + 10^?9, IVC  + 10^?9, IVM /IVC  + 10^?9). In Experiment 1, maturated oocytes from Control and IVM  + 10^?9 treatments showed increased glutathione content, mitochondrial membrane potential and percentage of Grade I blastocysts (40.6% and 43%, respectively). In Experiment 2, an increase in the percentage of Grade I blastocysts was detected in IVC  + 10^?7 (43.5%; 56.7%) and IVC  + 10^?9 (47.4%; 57.4%). Moreover, a lower number and percentage of apoptotic cells in blastocysts were observed in the IVC  + 10^?9 group compared to Control (3.8 ± 0.6; 3.6% versus 6.1 ± 0.6; 5.3%). In Experiment 3, the IVC  + 10^?9 treatment increased percentage of Grade I blastocysts with a lower number of apoptotic cells compared to IVM /IVC  + 10^?9 group (52.6%; 3.0 ± 0.5 versus 46.0%; 5.4 ± 1.0). The IVC  + 10^?9 treatment also had a higher mRNA expression of antioxidant gene (SOD 2) compared to the Control, as well as the heat shock protein (HSPB 1) compared to the IVM  + 10^?9. Reactive oxygen species production was greater in the IVM /IVC  + 10^?9 treatment group. In conclusion, the 10^?9 M concentration of melatonin and the in vitro production phase in which it is used directly affected embryonic development and quality.  相似文献   

A new standard area diagram set for assessment of severity of soybean rust improves accuracy of estimates and optimizes resource use     

Vinicius T. Franceschi  Kaique S. Alves  Sergio M. Mazaro  Cláudia V. Godoy  Henrique S. S. Duarte  Emerson M. Del Ponte 《Plant pathology》2020,69(3):495-505

Soybean rust (SBR), caused by Phakopsora pachyrhizi, is the most important yield-damaging fungal disease of soybean due to severe reduction in healthy leaf area and acceleration of leaf fall. In experimental research, SBR severity is estimated visually aided/trained by a standard area diagram (SAD) developed and validated during the mid-2000s (Old SAD). In this study, we propose a new SAD set for SBR with six true-colour diagrams following linear increments (c. 15% increments) amended with four additional diagrams at low (<10%) severities, totalling 10 diagrams (0.2%, 1%, 3%, 5%, 10%, 25%, 40%, 55%, 70%, and 84%). For evaluation, 37 raters were split into two groups. Each assessed severity in a 50-image sample (0.25%–84%), first unaided and then using either the Old SAD or the New SAD. Accuracy, precision, and reliability of estimates improved significantly relative to unaided estimates only when aided by the New SAD (accuracy >0.95). Low precision (<0.78) and a trend of underestimation with an increase in severity were the main issues with the Old SAD, which did not differ from unaided estimates. Simulation to evaluate the impact of the errors by different methods on hypothesis tests, showed that the new SAD was more powerful for detecting the smallest difference in mean control (e.g., 70% vs. 65% disease reduction) than the Old SAD; the latter required a 2-fold increase in sample size to achieve the same power. There is a need to improve some SADs, taking advantage of new knowledge and technology to increase accuracy of the estimates, and to optimize both resource use efficiency and management decisions.  相似文献   

Forage legumes in grass pastures in tropical Brazil and likely impacts on greenhouse gas emissions: A review     

Robert M. Boddey  Daniel Rume Casagrande  Bruno G. C. Homem  Bruno J. R. Alves 《Grass and Forage Science》2020,75(4):357-371

Beef cattle producers seldom use fertilizers for their pastures in tropical regions of Brazil. Slowly, this is changing but because of the need for repeated applications, N fertilizer is rarely applied. The introduction of a forage legume is an appropriate solution for this problem, but until recently adoption has been very low as the legumes generally have not persisted in the sward. We report research on how grazing management can affect the persistence of stoloniferous legumes in pastures of Brachiaria spp. and the problems of establishing and maintaining crown-forming legumes such as Stylosanthes spp. With suitable management, milk or bovine carcass yields can be equal or greater from mixed than from grass-alone pastures fertilized with 120 or 150 kg Nha^-1 year⁻¹. In addition to savings in CO₂ emissions from fossil fuels for the production and distribution of N fertilizers, nitrous oxide emissions from cattle excreta and legume residues are lower than those from N-fertilized brachiaria grass monocultures. Other studies indicate that enteric methane emissions from cattle may be mitigated when forage legumes are included in their diet. The use of forage legumes in mixed pastures for tropical regions is emerging as a feasible strategy to keep meat and milk production at acceptable levels with reduced greenhouse gas emission rates.  相似文献   

Pre-anaesthetic clinical examination influences anaesthetic protocol in dogs undergoing general anaesthesia and sedation     

L. F. Louro  T. Maddox  K. Robson  B. Alderson 《The Journal of small animal practice》2021,62(9):737-743

  相似文献   

Performance of feedlot lambs fed palm kernel cake-based diets     

Rozilda da Conceição dos Santos  Kaliandra Souza Alves  Rafael Mezzomo  Luis Rennan Sampaio Oliveira  Darley Oliveira Cutrim  Daiany Iris Gomes  Gilmara Pinto Leite  Marcio Yuri de Souza Araújo 《Tropical animal health and production》2016,48(2):367-372

  相似文献   

Effect of supplementation of beef cattle with different protein levels and degradation rates during transition from the dry to rainy season     

Rodolfo Maciel Fernandes  Chafic Mustafé de Almeida  Bruna Caldas Carvalho  João Alexandrino Alves Neto  Verônica Aparecida Costa Mota  Flávio Dutra de Resende  Gustavo Rezende Siqueira 《Tropical animal health and production》2016,48(1):95-101

  相似文献   

Herd-level prevalence and risk factors for bovine viral diarrhea virus infection in cattle in the State of Paraíba,Northeastern Brazil     

Leise Gomes Fernandes  Adriana Hellmeister de Campos Nogueira  Eliana De Stefano  Edviges Maristela Pituco  Cláudia Pestana Ribeiro  Clebert José Alves  Tainara Sombra Oliveira  Inácio José Clementino  Sérgio Santos de Azevedo 《Tropical animal health and production》2016,48(1):157-165

  相似文献   

A monoclonal antibody against a canine CD45 homologue: analysis of tissue distribution, biochemical properties and in vitro immunological activity     

Aguiar PH  Barrouin-Melo SM  Franke CR  dos Santos RR  Silva TM  Mengel JO  dos-Santos WL  Pontes-de-Carvalho L 《Veterinary journal (London, England : 1997)》2007,173(1):158-166

This report describes the characterisation of a monoclonal antibody (mAb), AB6, which recognises specifically a cluster of canine leukocyte surface molecules. The immunogen used for obtaining the AB6 mAb was a lysate of canine peripheral blood mononuclear cells (PBMC). This novel mAb belongs to the IgG2a isotype, and reacted in Western blot with four different canine leukocyte glycoproteins with apparent molecular weights of 180, 190, 205 and 220 kDa. The AB6 mAb recognised the majority of canine peripheral blood leukocytes as determined by flow cytometry (97%). It also exhibited a broad reactivity pattern against lymphoid and myeloid cells, inhibited the proliferation of mitogen-stimulated canine PBMC and did not recognise human PBMC and murine splenocytes. The biochemical properties, cell and tissue specificity, and in vitro biological activity of the AB6 mAb indicate that it recognises a canine CD45 homologue. The mAb could become a valuable diagnostic and research tool for the evaluation of immune functions in dogs.  相似文献