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101.
Comparative studies of ionic composition, osmolality, protein concentration and pH of seminal plasma along with spermatozoa concentrations were carried out in stellate sturgeon, Acipenser stellatus, and Russian sturgeon, Acipenser gueldenstaedtii. Analysis of A. gueldenstaedtii sperm showed significantly higher concentrations of Na+ (34.58 ± 4.61 mm ), Ca2+ (0.35 ± 0.12 mm ), Mg2+ (0.70 ± 0.25 mm ), Cl? (13.50 ± 4.04 mm ) and proteins (0.60 ± 0.29 mg/ml) in the seminal plasma than did seminal plasma of A. stellatus: Na+ (20.08 ± 10.75 mm ), Ca2+ (0.28 ± 0.06 mm ), Mg2+ (0.29 ± 0.05 mm ), Cl? (7.50 ± 3.00 mm ) and 0.30 ± 0.11 mg/ml proteins. Significantly higher concentration of K+ (5.42 ± 1.06 mm ) was observed in A. stellatus compared to A. gueldenstaedtii K+ (2.29 ± 0.50 mm ). Concentration of Na+ was positively correlated with osmolality (r = 0.819), levels of Cl? (r = 0.922) and Mg2+ (r = 0.727) and pH (r = 0.848). The concentration of Mg2+ was positively correlated with protein concentration (r = 0.774), Na+ (r = 0.727), Cl? (r = 0.872) and Ca2+ (r = 0.801). A positive relationship was also found between concentration of K+ and spermatozoa concentration (r = 0.709). Results revealed strong inter‐species differences in several parameters. The data should be useful for artificial fertilization and for cryopreservation of sturgeon sperm. 相似文献
102.
Within-leaf variations in cell size, mitochondrial numbers and dark respiration rates were compared in the most recently expanded tip, the mid-section and base of needles of Pinus radiata D. Don trees grown for 4 years in open-top chambers at ambient (36 Pa) or elevated (65 Pa) carbon dioxide partial pressure (p(CO2)a). Mitochondrial numbers and respiratory activity varied along the length of the needle, with the highest number of mitochondria per unit cytoplasm and the highest rate of respiration per unit leaf area at the base of the needle. Regardless of the location of the cells (tip, middle or basal sections), needles collected from trees grown in elevated p(CO2)a had nearly twice the number of mitochondria per unit cytoplasm as those grown in ambient p(CO2)a. This stimulation of mitochondrial density by growth at elevated p(CO2)a was greater at the tip of the needle (2.7 times more mitochondria than in needles grown in ambient CO2) than at the base of the needle (1.7 times). The mean size of individual mitochondria was unaffected either by growth at elevated p(CO2)a or by position along the needle. Tree growth at elevated p(CO2)a had a variable effect on respiration per unit leaf area, significantly increasing respiration in the tip of the needles (+25%) and decreasing respiration at the mid-section and base of the needles (-14% and -25%, respectively). Although a simple relationship between respiration per unit leaf area and mitochondrial number per unit cytoplasm was found within each CO2 treatment, the variable effect of growth at elevated p(CO2)a on respiration along the length of the needles indicates that a more complex relationship must determine the association between structure and function in these needles. 相似文献
103.
Crystalline abscisin II, with a tentative molecular formula of C(15)H(20)O(4), has been isolated from young cotton fruit. It accelerates abscission when applied in amounts as low as 0.01 microg per abscission zone. It inhibits indoleacetic acid-induced straight growth of Avena coleoptiles but has no gibberellin activity on dwarf maize. 相似文献
104.
105.
Baleeiro CO Paranhos-Silva M dos Santos JC Oliveira GG Nascimento EG de Carvalho LP dos-Santos WL 《Veterinary parasitology》2006,139(1-3):21-28
In this study, humoral (circulating anti-Leishmania antibodies) and cellular (Montenegro's skin test) immune responses of dogs from an endemic area of visceral leishmaniosis were tested using Leishmania chagasi, Leishmania amazonensis and Leishmania braziliensis antigens. The antibody response was tested in three animal groups, selected according to their anti-L. chagasi antibody activity, as measured by ELISA in the serum: 19 negative (O.D. below 0.30), seven with undefined (O.D. between 0.40 and 0.70) and 12 positive (O.D. above 1.0) ELISA result. In the group of animals with positive ELISA, the antibody activity against L. chagasi antigens (mean O.D.=1.31) was significantly higher (ANOVA, P<0.01) than against L. amazonensis (mean O.D.=0.88) or L. braziliensis (mean O.D.=0.87) antigens. The Montenegro's skin test results obtained with L. chagasi and L. braziliensis antigens showed a fair agreement (kappa=0.309). The same was observed when antigens from L. braziliensis and L. amazonensis were compared (kappa=0.374), whereas a moderate agreement between the results from tests performed with L. chagasi and L. amazonensis antigens was observed (kappa=0.530). The induration areas obtained with L. braziliensis antigen were smaller than those obtained with the other antigens. The data presented herein indicate that the use of antigens from different Leishmania species may interfere with the results of the immunological tests performed in dogs in an endemic area of visceral leishmaniosis. 相似文献
106.
Effect on Rendement Napole genotype on metabolic markers in Ossabaw pigs fed different levels of fat 下载免费PDF全文
H. Lu H. Yan M. G. Ward T. Stewart O. Adeola K. M. Ajuwon 《Journal of animal physiology and animal nutrition》2018,102(1):e132-e138
We investigated effects of Rendement Napole (RN ) genotype on metabolic markers in Ossabaw pigs fed diets with different levels of dietary fat. Thirty‐two pigs, belonging to either the wild‐type (WT , rn+/rn+) or carrier (CAR , RN ?/rn+) genotypes (n = 16/genotype), were divided into two dietary groups, (high fat [HF ] or low fat [LF ]) diets, for 12 weeks (n = 8 pigs/genotype/diet) after which pigs were killed for gene expression analysis by RT ‐PCR . Feeding HF diet caused increased daily gain (ADG , p < .05) and final body weight (BW ) (p < .05) in comparison with the LF diet (p < .05). Feed efficiency (gain:feed) was higher (p < .05) in pigs on the HF and was higher (p < .05) in CAR pigs compared to WT . There was genotype × diet interaction (p = .05) on final BW such that CAR animals on LF diet had the same final BW as animals of both genotypes on HF diet. Carrier pigs on LF diet had higher (p < .05) average daily gain and gain:feed than WT pigs. There was a trend (p < .08) for a higher feed consumption in pigs on the LF diet. Backfat thickness was higher (p < .01) in pigs on the HF diet. Serum triglyceride was higher (0.62 vs. 0.33 mg/dl, p < .01) in pigs on HF diet. Serum insulin was higher (p < .05) in CAR versus WT pigs (0.40 vs. 0.015 μg/ml). Pigs on the HF diet had a higher (p < .05) serum insulin compared to those on the LF diet (0.032 vs. 0.023 μg/ml). Carnitine palmitoyl transferase 1‐alpha was higher (p < .05) in the longissimus dorsi and semitendinosus muscles of pigs on HF diet. Acyl‐CoA oxidase I was elevated (p < .05) in the liver of pigs on HF diet. Fatty acid synthase was lower in the longissimus dorsi muscle, liver and mesenteric fat (p < .05) of carrier pigs. The RN gene regulates specific metabolic markers in the Ossabaw pigs. 相似文献
107.
Raw mechanically separated chicken meat and salmon protein hydrolysate as protein sources in extruded dog food: effect on protein and amino acid digestibility 下载免费PDF全文
M. T. Tjernsbekk A.‐H. Tauson O. F. Kraugerud Ø. Ahlstrøm 《Journal of animal physiology and animal nutrition》2017,101(5):e323-e331
Protein quality was evaluated for mechanically separated chicken meat (MSC) and salmon protein hydrolysate (SPH), and for extruded dog foods where MSC or SPH partially replaced poultry meal (PM). Apparent total tract digestibility (ATTD) of crude protein (CP) and amino acids (AA) in the protein ingredients and extruded foods was determined with mink (Neovison vison). The extruded dog foods included a control diet with protein from PM and grain, and two diets where MSC or SPH provided 25% of the dietary CP. Nutrient composition of the protein ingredients varied, dry matter (DM) was 944.0, 358.0 and 597.4 g/kg, CP was 670.7, 421.2 and 868.9 g/kg DM, crude fat was 141.4, 547.8 and 18.5 g/kg DM and ash was 126.4, 32.1 and 107.0 g/kg DM for PM, MSC and SPH respectively. The content of essential AA (g/100 g CP) was more than 10.0 percentage units lower in SPH than in PM and MSC. The ATTD of CP differed (p < 0.001) between protein ingredients and was 80.9%, 88.2% and 91.3% for PM, MSC and SPH respectively. The ATTD of total AA was lowest (p < 0.001) for PM, and similar (p > 0.05) for MSC and SPH. In the extruded diets, the expected higher ATTD of CP and AA from replacement of PM with MSC or SPH was not observed. The ATTD of CP was determined to be 80.3%, 81.3% and 79.0% for the PM, MSC and SPH extruded foods respectively. Furthermore, the ATTD of several AA was numerically highest for the PM diet. Possibly, extrusion affected ATTD of the diets differently due to different properties and previous processing of the three protein ingredients. 相似文献
108.
The EFSA quantitative approach to pest risk assessment – methodological aspects and case studies 下载免费PDF全文
G. Gilioli G. Schrader J.‐C. Grégoire A. MacLeod O. Mosbach‐Schulz T. Rafoss V. Rossi G. Urek W. van der Werf 《EPPO Bulletin》2017,47(2):213-219
A new method for pest risk assessment and the identification and evaluation of risk‐reducing options is currently under development by the European Food Safety Authority (EFSA) Plant Health Panel. The draft method has been tested on pests of concern to the European Union (EU). The method is adaptable and can focus either on all the steps and sub‐steps of the assessment process or on specific parts if necessary. It is based on assessing changes in pest population abundance as the major driver of the impact on cultivated plants and on the environment. Like other pest risk assessment systems the method asks questions about the likelihood and magnitude of factors that contribute to risk. Responses can be based on data or expert judgment. Crucially, the approach is quantitative, and it captures uncertainty through the provision by risk assessors of quantile estimates of the probability distributions for the assessed variables and parameters. The assessment is based on comparisons between different scenarios, and the method integrates risk‐reducing options where they apply to a scenario, for example current regulation against a scenario where risk‐reducing options are not applied. A strategy has been developed to communicate the results of the risk assessment in a clear, comparable and transparent way, with the aim of providing the requestor of the risk assessment with a useful answer to the question(s) posed to the EFSA Plant Health Panel. The method has been applied to four case studies, two fungi, Ceratocystis platani and Cryphonectria parasitica, the nematode Ditylenchus destructor and the Grapevine flavescence dorée phytoplasma. Selected results from these case studies illustrate the types of output that the method can deliver. 相似文献
109.
Intraocular pressure (IOP) was measured in normal dairy cows by applanation tonometry. In the first study of 15 Holstein and 17 Jersey cows the mean IOP by Mackay-Marg tonometry was 27.5 ± 4.8 mmHg (range 16–39 mmHg); no significant differences ( P < 0.92) were observed between the Holstein and Jersey breeds. In the second study of 15 Holstein and 12 Jersey cows, the mean IOPs by Mackay-Marg and TonoPen-XL tonometry were 28.2 ± 4.6 mmHg (range 19–39 mmHg) and 26.9 ± 6.7 mmHg (range 16–42 mmHg), respectively. Comparisons of the Mackay-Marg and TonoPen tonometers indicated no significant differences ( P < 0.16). The mean and range of IOP in normal dairy cows within 2 SD (95% of the population) is 27 mmHg with a range of 16–36 mmHg. 相似文献
110.
C. de Fourmestraux O. Geffroy B. Siliart O. Albaric C. Tessier 《Equine Veterinary Education》2014,26(1):34-39
The surgical success of laparoscopic castration without orchidectomy results from avascular necrosis of the testes. However, failures and subsequent production of testosterone and stallion‐like behaviour have been previously identified. Laparoscopic castration without removal of the testes was performed in 32 horses with 2 normal descended scrotal testes between July 2006 and October 2012. The objectives of our study were to evaluate the success rate of laparoscopic castration without orchidectomy on descended testes in our population and assess complications and recovery time. Endocrine tests were performed after surgery and owners also asked to report on their horse's behaviour and ability to resume exercise. Castration was deemed successful if endocrine test results were in accordance with gelding values. Failed horses were castrated using a conventional technique and histology performed when possible. Basal testosterone levels decreased below 3 nmol/l after surgery in 30/32 cases. However, in 2 horses, stallion behaviour persisted and histological evaluation after inguinal castration showed residual viable tissue. Two horses maintained high testosterone levels after surgery associated with stallion‐like behaviour. Based on these results, 12.5% of horses (4/32 horses) failed to be considered a gelding based on either endocrine tests and/or histology. All horses, with one exception, were able to resume exercise less than a week after the procedure. Laparoscopic castration without orchidectomy appears to be a safe procedure. When assessing the success of laparoscopic castration, our total failure rate was 12.5% (4/32 horses) which is significantly higher than previously reported. 相似文献