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排序方式: 共有204条查询结果,搜索用时 31 毫秒
181.
182.
JL Yániz F López‐Gatius I García‐Ispierto G Bech‐Sàbat B Serrano C Nogareda JA Sanchez‐Nadal S Almeria P Santolaria 《Reproduction in domestic animals》2010,45(4):699-705
The aim of this study was to determine if the factors affecting the abortion rate in dairy herds with high incidence of Neospora‐associated abortions are different in pregnancies of cows and heifers chronically infected with Neospora caninum. In heifers (n = 229), an increase in the cumulative number of days with a mean relative humidity (RH) lower than 60% during the second trimester of gestation increases the risk of abortion. Yet, the likelihood of abortion was 7.6 times lower for pregnant heifers inseminated with Limousin bull semen, compared with those inseminated with Holstein‐Friesian bull semen. In pregnancies of parous cows (n = 521), an increase in rainfall and in the cumulative number of days with a mean RH lower than 60% during the second trimester of gestation increased the abortion rate. However, in contrast, an increase in the lactation number produced a decrease in the abortion rate, with a likelihood of abortion 4.8 times lower for pregnant cows inseminated with Limousin bull semen, and three times lower for those inseminated with Belgian Blue bull semen, compared with dairy cows inseminated with Holstein‐Friesian bull semen. Finally, the likelihood of abortion was 3.2 times lower for pregnancies of parous cows with low antibody titres against N. caninum (6–30 units) as compared to those with high antibody titres (≥30 units), whereas in heifers this variable had no effect. The practical recommendations of the present study include the control of the cow environment during the second trimester of gestation, the priority of culling for parous cows with higher antibody titres against N. caninum and the insemination of Neospora‐seropositive cows with semen from the Limousin breed. 相似文献
183.
Tolina T. Son DVM Lisa Thompson DVM DACVECC Sergi Serrano LV DACVECC Ravi Seshadri DVM DACVECC DAVBP 《Journal of Veterinary Emergency and Critical Care》2010,20(4):426-435
Objective – To evaluate clinical characteristics and outcomes of cats undergoing surgical intervention in the course of treatment for severe acute pancreatitis. Design – Retrospective observational study from 2003 to 2007 with a median follow‐up period of 2.2 years (range 11 d–5.4 y) postoperatively. Setting – Private referral veterinary center. Animals – Eight cats. Interventions – None. Measurements and Main Results – Quantitative data included preoperative physical and clinicopathologic values. Qualitative parameters included preoperative ultrasonographic interpretation, perioperative and intraoperative feeding tube placement, presence of free abdominal fluid, intraoperative closed suction abdominal drain placement, postoperative complications, microbiological culture, and histopathology. Common presenting clinical signs included lethargy, anorexia, and vomiting. Leukocytosis and hyponatremia were present in 5 of 8 cats. Hypokalemia, increased total bilirubin, and hyperglycemia were present in 6 of 8 cats. Elevated alanine aminotransferase and aspartate transferase were present in all cats. Surgery for extrahepatic biliary obstruction was performed in 6 cats, pancreatic abscess in 3 cats, and pancreatic necrosis in 1 cat. Six of the 8 cats survived. Five of the 6 cats that underwent surgery for extrahepatic biliary obstruction and 1 cat that underwent pancreatic necrosectomy survived. All 5 of the cats with extrahepatic biliary obstruction secondary to pancreatitis survived. The 2 nonsurvivors included a cat with a pancreatic abscess and a cat with severe pancreatitis and extrahepatic biliary obstruction secondary to a mass at the gastroduodenal junction. Postoperative complications included progression of diabetes mellitus, septic peritonitis, local gastrostomy tube stoma inflammation, local gastrostomy tube stoma infection, and mild dermal suture reaction. Conclusion – Cats with severe acute pancreatitis and concomitant extrahepatic biliary obstruction, pancreatic necrosis, or pancreatic abscesses may benefit from surgical intervention. Cats with extrahepatic biliary obstruction secondary to severe acute pancreatitis may have a good prognosis. 相似文献
184.
Effect of biofumigation with brassica pellets combined with Brassicaceae cover crops and plastic cover on the survival and infectivity of inoculum of Phytophthora nicotianae Breda de Haan
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M. Carmen Rodríguez‐Molina Paula Serrano‐Pérez Carolina Palo 《Pest management science》2016,72(7):1295-1301
185.
In this paper the authors inquire why, after more than 25 years of domestic agricultural reforms in Mexico and 15 years of trade liberalization of maize under the North American Free Trade Agreement (NAFTA), the domestic production of maize, a non-competitive crop and the major staple in Mexico, has increased. The authors present new empirical evidence showing that, as expected, maize prices in Mexico dropped until 2006 and have experienced a process of convergence with USA prices, and maize imports from the USA have increased. However, despite lower prices, maize production in Mexico has trended upward since 1992, two years before the beginning of NAFTA's implementation. Based on the heterogeneity of maize production in Mexico, three possible explanations are proposed to explain this unexpected outcome: government supports to big commercial farmers in the agriculturally rich North of Mexico; the persistence of maize production by subsistence farmers; and to a lesser degree, increasing yields on some irrigated maize farms. We finish the paper by drawing lessons from the experience of Mexico for other Less Developed Countries. 相似文献
186.
A. Martínez-Royo L. Ordovas P. Zaragoza J. Altarriba M. Serrano C. Rodellar J.H. Calvo 《Research in veterinary science》2010,88(3):452-455
On the basis of QTL studies for milk-fat yield trait on BTA3, annexin 9 protein (ANXA9), fatty acid transport protein type 3 (SLC27A3) and diacylglycerol O-acyltransferase 1 (DGAT1) were selected as candidate genes. Three different single nucleotide polymorphisms (SNPs) of bovine ANXA9, SLC27A3 and DGAT1 genes have been tested in a selective genotyping design for milk-fat yield. Significant allele frequency differences were found for ANXA9 (p = 0.02), in Holstein–Friesian animals with high and low breeding values for milk-fat yield. Regression analysis also showed a significant effect (p = 0.0207) between estimated breeding values (EBVs) for fat milk content and ANXA9 polymorphism. So ANXA9 gene falls into a significant quantitative trait loci interval for milk-fat yield that was previously reported on bovine chromosome 3 in other dairy populations. Our results suggest that the ANXA9 gene polymorphism or a linked segregating QTL contributes to variation in milk-fat yield. 相似文献
187.
Broderick G A Reynal S M 《饲料博览》2009,(8):44-44
试验旨在研究微粉化(细磨)豆粕(SBM)和全脂大豆(FFSB)对23日龄肉鸡氨基酸的表观回肠消化率系数(CIAD)和真消化率系数(CITD)的影响。试验采用完全随机区组设计,按饲粮分为4个处理组,即微粉化SBM组、微粉化FFSB组、粗糙SBM组、粗糙FFSB组,每个处理组设6个重复,每个重复8只。微粉化SBM和FFSB的平均粒径(MPS)分别为47和41μm,而粗糙SBM和FFSB的平均粒径分别为881和778μm。 相似文献
188.
Experimental studies in pigs on Trichinella detection in different diagnostic matrices 总被引:10,自引:0,他引:10
A total of 72 specific pathogen-free (SPF) and Iberian pigs (three animals per group) were inoculated with 200, 1000 or 20,000 muscle larvae of T. spiralis, T. nativa, T. britovi and T. pseudospiralis. For each animal, the muscle larva burden was evaluated in nine muscle samples by digestion. The anti-Trichinella IgG kinetics in blood samples, taken twice prior and at days 5, 10, 15, 20, 25, 30, 40, 50 and 60 post-inoculation, and in muscle juice, obtained at necropsy, was evaluated by an ELISA using an excretory/secretory antigen. The mean larval recovery rate in SPF/Iberian pigs corresponded with the level of inoculum dose, and tongue, diaphragm and masseter were identified as predilection muscles. In SPF and Iberian pigs receiving 20,000 larvae of T. spiralis, an earlier seroconversion was detected from day 25 post-inoculation. At a 10-fold dilution, the muscle juice showed a good test agreement with blood serum. 相似文献
189.
190.
McCluskey BJ Salman MD Martínez GE Serrano AO Shaw JL Herrerro MV 《Preventive veterinary medicine》2003,58(3-4):199-210
The occurrence of vesicular stomatitis (VS) was investigated in El Salvador through monthly visits to 12 sentinel cattle operations located in four different departments. Management, environmental, and spatial data were collected. Heifers were enrolled on the operations and were examined and bled monthly for 3 years. Two competitive ELISAs were used to detect antibodies on each sample for each serotype of VS virus (VSV). On 8 of the 12 operations, small terrestrial rodents were trapped, blood samples collected, and antibodies to both VS serotypes evaluated using a serum-neutralization test for each virus serotype.
Similar to other studies of VS in Central America, the seroprevalence of the New Jersey serotype was higher than the seroprevalence to the Indiana serotype. An outbreak of VS appeared to occur in the Department of Sonsonate in the summer of 1999. We confirmed that VS is endemic in the four departments investigated in El Salvador. 相似文献