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Priscila de Andrade Rode Maicon Toldi Marliza Beatris Reichert Liana Johann Noeli Juarez Ferla 《Phytoparasitica》2018,46(1):137-141
The aim of this study was to assess the influence of transgenic soybean [Glycine max L. (Fabaceae)] cultivars on the biological cycle of Tetranychus ludeni Zacher (Acari: Tetranychidae) in laboratory conditions. We used three cultivars: a conventional soybean (CO), a glyphosate-resistant with insertion of genes of Agrobacterium sp., Roundup Ready (RR), and a glyphosate-resistant with insertion of genes of Bacillus thuringiensis var. israelensis (BT). Duration of developmental stage, mite viability, number of laid eggs, and female longevity of T. ludeni were evaluated. The duration of the deutonymph phase was shorter in RR (2.1?±?0.12 days) than in CO (2.6?±?0.12) and BT (2.5?±?0.08). The duration of egg, larval, and protonymph phases were similar for T. ludeni on the three cultivars. The mean duration of each generation (T), net reproduction rate (Ro), intrinsic rate of natural increase (rm), and doubling time (DT) were similar on the three cultivars. Results showed that population growth are not influenced by transgenesis at the laboratory level. Females died without a post-oviposition period on all soybean cultivars. The intrinsic rate of natural increase of T. ludeni on soybean cultivars was low (between 0.15 and 0.17). 相似文献
13.
Validation of the FACSCount AF System for Determination of Sperm Concentration in Boar Semen 总被引：3，自引：0，他引：3
C Hansen P Christensen H Stryhn AM Hedeboe M Rode G Boe-Hansen 《Reproduction in domestic animals》2002,37(6):330-334
A flow cytometric method has been developed for rapid determination of sperm concentration in semen from various mammalian species. * * Patent Pending, Int. Publication Number WO/00/54026.
All cells containing DNA are stained with SYBR‐14 or propidium iodide (PI) and sperm concentration is determined in relation to an internal standard of fluorescent microspheres (beads). Satisfactory staining can be achieved within 2–3 min and the following flow cytometric analysis on the FACSCount AF System rapidly provides the user with a precise and accurate assessment of the sperm concentration. In this study, the FACSCount AF System and Sperm Counting Reagent (BD Biosciences) was compared with microscopic counting using a Bürker–Türk haemocytometer. In addition, sperm concentration was determined using the Corning 254 spectrophotometer which is used routinely by Danish artificial insemination stations for boars. The results show that the agreement between flow cytometry and microscopic counting is very high. The slope for the regression line was 1.12 (SE = 0.03) with an estimated intercept with the Y‐axis of 22 × 106sperm/ml (SE = 10 × 106 sperm/ml) and an estimated error of the model of 10 × 106 sperm/ml. For the spectrophotometer, the slope of the regression line was 1.09 (SE = 0.07) with an estimated intercept of 137 × 106 sperm/ml (SE = 25 × 106 sperm/ml). The average error made by the spectrophotometer was 55 × 106 sperm/ml. In addition, the results obtained using flow cytometry was highly repeatable (CV = 2.7%) in comparison with the spectrophotometric method (CV = 6.3%). These results indicate that the FACSCount AF System is a valuable tool for precise and accurate assessment of sperm concentration in boar semen and that use of this system may lead to production of more uniform insemination doses containing a specific number of sperm per dose. 相似文献
All cells containing DNA are stained with SYBR‐14 or propidium iodide (PI) and sperm concentration is determined in relation to an internal standard of fluorescent microspheres (beads). Satisfactory staining can be achieved within 2–3 min and the following flow cytometric analysis on the FACSCount AF System rapidly provides the user with a precise and accurate assessment of the sperm concentration. In this study, the FACSCount AF System and Sperm Counting Reagent (BD Biosciences) was compared with microscopic counting using a Bürker–Türk haemocytometer. In addition, sperm concentration was determined using the Corning 254 spectrophotometer which is used routinely by Danish artificial insemination stations for boars. The results show that the agreement between flow cytometry and microscopic counting is very high. The slope for the regression line was 1.12 (SE = 0.03) with an estimated intercept with the Y‐axis of 22 × 106sperm/ml (SE = 10 × 106 sperm/ml) and an estimated error of the model of 10 × 106 sperm/ml. For the spectrophotometer, the slope of the regression line was 1.09 (SE = 0.07) with an estimated intercept of 137 × 106 sperm/ml (SE = 25 × 106 sperm/ml). The average error made by the spectrophotometer was 55 × 106 sperm/ml. In addition, the results obtained using flow cytometry was highly repeatable (CV = 2.7%) in comparison with the spectrophotometric method (CV = 6.3%). These results indicate that the FACSCount AF System is a valuable tool for precise and accurate assessment of sperm concentration in boar semen and that use of this system may lead to production of more uniform insemination doses containing a specific number of sperm per dose. 相似文献
14.
Effects of protozoa on bacterial nitrogen recycling in the rumen 总被引：7，自引：0，他引：7
The effects of protozoa on ruminal NH3-N kinetics and bacterial N recycling were measured in five sheep (57.6+/-7.1 kg BW, x +/- SD) with ruminal and duodenal cannulas in naturally faunated, defaunated, and refaunated periods. The sheep were fed a diet of 239 g of alfalfa haylage and 814 g of barley concentrate per day (DM basis) divided into 12 equal portions and allocated at 2-h intervals. A pulse dose of 300 mg of 15N as [15N]NH4Cl was administered into the rumen (on d 1 and 15) and 300 mg of 15N as [15N]urea was administered intravenously to the blood (d 8). Enrichment of 15N was measured in ruminal NH3-N, bacterial N, and plasma urea N over a period of 35 h. Total collection of urine was made for 5 d and analyzed for purine derivatives to calculate the flow of microbial N. Ruminal parameters and nutrient digestibilities were also measured. Sheep were defaunated using a rumen washing procedure 50 d prior to measurements in the defaunated period. Sheep were refaunated with ruminal contents from a faunated sheep receiving the same diet. Measurements began 26 d following refaunation, at which time protozoal numbers had returned to those in the originally faunated sheep. Data reported in parentheses are for faunated, defaunated, and refaunated sheep, respectively. Total culturable and cellulolytic bacterial numbers were unaffected by defaunation, but there was an increase in flow of microbial N from the rumen (10.8, 17.3, and 11.1 g N/d; P < .05) in the defaunated period. Flux, irreversible loss, and intraruminal recycling of NH3-N and recycling of NH3-N from plasma urea N were not affected by defaunation. Defaunation had no effect on reducing the absolute amount (13.8, 10.0, and 11.3 g N/d; P > .20) of bacterial N recycling and the percentage of N flux through the bacterial N pool. Total-tract digestion was reduced in defaunated compared with faunated sheep by 8, 17, 15, and 32% for OM, N, NDF, and ADF, respectively. In conclusion, defaunation improved ruminal N metabolism through the enhancement of bacterial protein synthesis, and improvement in the flow of microbial protein to the host animal. 相似文献
15.
Effects of dietary factors including kernel thickness of processed barley grain, ratio of forage to concentrate, and forage particle length on chemical composition of bacteria, bacterial colonization of feed particles and distribution in the rumen, and duodenal flow of bacteria in dairy cows were evaluated. The experiment was designed as a double 4 x 4 quasi-Latin square with a 2 x 2 x 2 factorial arrangement of treatments using eight lactating cows with ruminal and duodenal cannulas. Barley grain was steam-rolled to two thicknesses: coarse (1.60 mm) or flat (1.36 mm); ratio of forage:concentrate was low (35:65) or high (55:45) (DM basis); and forage particle length was long (7.59 mm) or short (6.08 mm). Cows were offered ad libitum access to a total mixed diet. Chemical composition was different (P < 0.01) between liquid-associated bacteria (LAB) and solid-associated bacteria (SAB). Reduced barley thickness increased (P < 0.05) N content and 15N enrichment, but a high ratio of forage:concentrate decreased (P < 0.01) 15N enrichment of both the LAB and SAB. Significant differences between AA composition of the LAB and SAB were observed for 15 out of 17 AA studied. Bacterial colonization was linearly increased (P < 0.01) from about 5 to 70% as particle length of rumen contents was reduced from 3.35 mm to 0.15 mm (sieve size). The degree of colonization on each fraction of the rumen particulate matter was only affected (P < 0.10) by the ratio of forage:concentrate, with consistently higher (P < 0.10) bacterial colonization noted for high than for low forage:concentrate diets. Of the total bacterial mass within the rumen, less than 20% was associated with the liquid and over 70% was associated with the small particles that passed through the 0.6-mm sieve. Although the bacterial pool in the rumen was lower (P < 0.04) when flatly rolled barley rather than coarsely rolled barley was fed, bacterial flow to the duodenum was greater (P < 0.10) with increasing ratio offorage:concentrate. The present results confirm the differences of chemical composition and biomass for LAB and SAB. Manipulation of dietary factors such as ratio of forage:concentrate have the potential to alter bacterial colonization of rumen particles and the relative proportion of LAB to SAB, which were positively correlated to bacterial flow to the duodenum. 相似文献
16.
Resistance of feed enzymes to proteolytic inactivation by rumen microorganisms and gastrointestinal proteases. 总被引：4，自引：0，他引：4
D P Morgavi K A Beauchemin V L Nsereko L M Rode T A McAllister A D Iwaasa Y Wang W Z Yang 《Journal of animal science》2001,79(6):1621-1630
Potential feed enzyme additives for ruminants were tested in vitro for their stability to ruminal microbial and gastrointestinal proteolysis. Four commercial preparations from Trichoderma longibrachiatum (A, B, C, and D) and one from an undisclosed source (E) were incubated up to 6 h with ruminal fluid taken from four lactating dairy cows before or 2 h after feeding. The stability of preparation B was also tested in the presence of pepsin at pH 3 and pancreatin at pH 7. Cellulase (EC 3.2.1.4), cellulose 1,4-beta-cellobiosidase (EC 3.2.1.91), beta-glucanase (EC 3.2.1.6), xylanase (EC 3.2.1.8), beta-glucosidase (EC 3.2.1.21), and beta-xylosidase (EC 3.2.1.37) activities were monitored throughout the incubations. Polysaccharidase activities of all enzyme preparations were remarkably stable in ruminal fluid taken after feeding. Ruminal fluid obtained before feeding inactivated the polysaccharidases in preparations B and D to a greater extent than ruminal fluid obtained after feeding. Cellulase and cellulose 1,4-beta-cellobiosidase activities were the least stable, declining (P < 0.05) by 35 and 60% for preparations B and D, respectively. Xylanase activity of preparation D decreased (P < 0.05) by up to 30% after 6 h of incubation, whereas beta-glucanase activity was not affected. The ability to degrade exogenous enzymes also differed among cows (P < 0.05). Pepsin and acid (pH 3.0) did not affect polysaccharidases in preparation B but decreased glycosidase activities by 10 to 15% (P < 0.05) after 1 h of incubation. Pancreatin, at the maximum concentration used, inactivated cellulase, cellulose 1,4-beta-cellobiosidase, and xylanase activities at a rate of 0.55, 1, and 0.45%/min, respectively. beta-Glucosidase and beta-xylosidase activities decreased by 1 and 0.75%/min, respectively. Partial proteolysis of cellulase, cellulose 1,4-beta-cellobiosidase, and xylanase by pancreatin produced a transient increase in activity. This twofold increase for cellulase and fourfold increase for cellulose 1,4-beta-cellobiosidase was directly proportional to pancreatin concentration. These results suggest that the enzyme feed additives tested were stable in the rumen of animals after feeding. Exogenous enzymes are likely to be more susceptible to the host gastrointestinal proteases in the abomasum and intestines than to ruminal proteases. However, exogenous polysaccharidases may survive for a considerable period of time in the small intestine and they probably maintain activity against target substrates in this environment. 相似文献
17.
Effects of barley grain processing on the site and extent of digestion of beef feedlot finishing diets 总被引：6，自引：0，他引：6
Effects of extent of barley rolling on chewing activities, ruminal fermentation, and site and extent of digestion were evaluated for feedlot finishing cattle diets in a 4 x 4 Latin square design. Four Jersey steers (452 kg), cannulated in the rumen and duodenum, were used. Barley grain was temper-rolled to four extents: coarse, medium, medium-flat, and flat, which were expressed as processing index (PI, volume weight of barley after processing expressed as a percentage of its volume weight before processing, DM basis) and equivalent to 82, 75, 70, and 65%, respectively. Diets consisted of 9.7% barley silage, 86% temper-rolled barley, and 4.3% other ingredients (DM basis). Steers were offered ad libitum access to a total mixed ration once daily. Dry matter intake was not affected (P > 0.15) by PI of barley. Digestibility of OM in the rumen and in the total tract were numerically lower (P = 0.13) for steers fed coarsely rolled barley than for steers fed more extensively processed barley. Digestibility of starch in the total tract was linearly increased (P = 0.02) with grain processing, but NDF digestion was not affected by processing (P > 0.15). Digestibility of CP did not differ in the rumen but tended (P = 0.08) to increase in the total tract with increased processing of barley. Flow of microbial nitrogen to the duodenum was approximately one-third lower (linear effect, P = 0.06) for steers fed coarsely rolled barley than for steers fed further rolled barley. Increased grain processing tended to decrease (linear effect, P = 0.08) rumination time without affecting eating time. These results indicate that optimal degree of rolling for barley fed to feedlot cattle corresponded to a PI of 75% or lower. Coarsely rolled barley is not recommended because it resulted in the lowest digestibility and lowest microbial protein synthesis. Processing barley to attain a PI less than 75% resulted in marginal improvements in feed digestion, but rumination time decreased, which could lead to problems associated with acidosis if lower-fiber diets are used. 相似文献
18.
Experiments were initiated to select a sterilization method(s) that minimizes alterations in the digestive properties of cereal grains and, thus, would be suitable for the study of cereal grain digestion by pure cultures of ruminal bacteria. The following five treatments were examined: unsterilized (U), autoclaving with buffer (AB), autoclaving without buffer (AD), ethylene oxide (E), and gamma irradiation (I). Solubility of DM, starch, and CP was determined by soaking grain in buffer for 1 h followed by filtration through Whatman #54 filter paper. Ground corn and wheat from each treatment were placed in vials with a 1:1 mixture of Bryant's medium and ruminal inoculum. Vials were incubated for 4, 8, 12, 24, and 48 h and analyzed for starch content. Bacterial growth was not evident in sterilized, uninoculated samples. The AD treatment decreased the disappearance of CP in wheat and corn, whereas AB caused an increase in the disappearance of DM, CP, and starch in wheat (P less than .001) compared with U. Rates of microbial starch digestion for corn were 1.3, 1.5, 3.3, 14.7, and 3.5%/h and for wheat were 1.3, 3.4, 4.6, 17.1, and 4.6%/h for AD, E, I, AB, and U, respectively. Contrasts indicated that AD and AB differed (P less than .001) from U for both corn and wheat. It is likely that gelatinization of cereal starch enhanced microbial starch digestion in AB and the formation of Maillard products reduced starch digestion in AD. Corn and wheat sterilized with E or I had digestive properties that closely resembled those of U grain, and either sterilization method was suitable for studying cereal grain digestion. 相似文献
19.
J W Ludders J Rode G S Mitchell E V Nordheim 《American journal of veterinary research》1989,50(2):245-249
Effects of ketamine, xylazine, and a combination of ketamine and xylazine were studied in 12 male Pekin ducks (7 to 12 weeks old; mean [+/- SD] body weight, 3.1 +/- 0.3 kg). After venous and arterial catheterization and fixation of a temperature probe in the cloaca, each awake duck was confined, but not restrained, in an open box in a dimly lit room. Blood pressure and lead-II ECG were recorded. Three arterial blood samples were collected every 15 minutes over a 45-minute period (control period) and were analyzed for pHa, PaCO2 and PaO2. After the control period, each duck was assigned at random to 1 of 3 drug groups: (1) ketamine (KET; 20 mg/kg of body weight, IV), (2) xylazine (XYL; 1 mg/kg, IV), and (3) KET + XYL (KET 20 mg/kg and XYL, 1 mg/kg; IV). Measurements were made at 1, 5, 10, 15, 30, 45, 60, and 90 minutes after drug administration. All ducks survived the drug study. Cloacal temperature was significantly (P less than or equal to 0.05) increased above control cloacal temperature at 90 minutes after the administration of ketamine, and from 10 through 90 minutes after administration of ketamine plus xylazine. In ducks of the KET group, pHa, PaCO2, and PaO2, remained unchanged after administration of the drug. In ducks of the XYL group, pHa and PaO2 decreased significantly (P less than or equal to 0.05) from control values for all time points up to and including 15 minutes after drug administration.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
20.
B. Rode S. V. Bavdek G. Lackovi&#; G. Fazarinc A. Bidovec 《Anatomia, histologia, embryologia》1998,27(3):187-192
The immunohistochemical study of chamois (Rupicapra rupicapra L.) skin showed that a limited number of available monoclonal and polyclonal antibodies expressed reactivity with skin cell components. These included cytokeratins, vimentin, desmin, neuron-specific enolase and S-100 protein with almost the same distribution pattern as already described in the skin of humans and animals. Antibodies used for labelling skin-associated lymphoid tissues and other cells with the immuno-logic function in human skin failed to demonstrate these cells in the chamois skin with the exception of LCA and OKT6 antibodies. Epidermal Langerhans cells were reliably demonstrated only by the enzyme histochemical method for adenosine triphosphatase, while the majority of mononuclear cells in dermal infiltrates showed a strong immunoreaction with OKT6 antibody. The histologic and histochemical analysis showed that the dermal infiltrations in infested skin consisted of macro-phages, lymphocytes, granulocytes, mastocytes and fibroblasts. The chamois skin affected with sarcoptes mange showed a significant loss of cytokeratins in the epidermis and its derivatives. Particular keratinocytes showing nonspecific staining with several antibodies were also described and discussed in this paper. 相似文献