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101.
Sheep milk is mainly intended to manufacture a wide variety of high-quality cheeses. The ovine cheese industry would benefit from an improvement, through genetic selection, of traits related to the milk coagulation properties (MCPs) and cheese yield-related traits, broadly denoted as “cheese-making traits.” Considering that routine measurements of these traits needed for genetic selection are expensive and time-consuming, this study aimed to evaluate the accuracy of a cheese-making phenotype imputation method based on the information from official milk control records combined with the pH of the milk. For this study, we analyzed records of milk production traits, milk composition traits, and measurements of cheese-making traits available from a total of 1,145 dairy ewes of the Spanish Assaf sheep breed. Cheese-making traits included five related to the MCPs and two cheese yield-related traits. The milk and cheese-making phenotypes were adjusted for significant effects based on a general linear model. The adjusted phenotypes were used to define a multiple-phenotype imputation procedure for the cheese-making traits based on multivariate normality and Markov chain Monte Carlo sampling. Five of the seven cheese-making traits considered in this study achieved a prediction accuracy of 0.60 computed as the correlation between the adjusted phenotypes and the imputed phenotypes. Particularly the logarithm of curd-firming time since rennet addition (logK20) (0.68), which has been previously suggested as a potential candidate trait to improve the cheese ability in this breed, and the logarithm of the ratio between the rennet clotting time and the curd firmness at 60 min (logRCT/A60) (0.65), which has been defined by other studies as an indicator trait of milk coagulation efficiency. This study represents a first step toward the possible use of the phenotype imputation of cheese-making traits to develop a practical methodology for the dairy sheep industry to impute cheese-making traits only based on the analysis of a milk sample without the need of pedigree information. This information could be also used in future planning of specific breeding programs considering the importance of the cheese-making efficiency in dairy sheep and highlights the potential of phenotype imputation to leverage sample size on expensive, hard-to-measure phenotypes.  相似文献   
102.
Tropical Animal Health and Production - The possible influence of the “male effect” upon reproductive outcomes of adult anestrous goats under marginal rangeland conditions and...  相似文献   
103.
104.

Context

The knowledge on cambial activity in water-limited environments, such as the Mediterranean, is still fragmentary. Dendrochronological studies have determined that spring precipitation plays an important part in determining tree-ring width and the properties of tracheids. However, the complex relation between cambial phenology and climate is still far from understood.

Aims

We studied the influence of climate, especially water stress, on maritime pine wood formation with the aim of determining the influence of drought on cambial activity.

Methods

A plantation of maritime pine (Pinus pinaster) was selected in the west coast of Portugal, to monitor cambial activity and wood formation using anatomical observations and band dendrometers. The trees were monitored weekly over 2 years (2010 and 2011).

Results

Xylem differentiation started earlier when warmer late winter temperatures were observed. Water stress triggered an earlier stop of wood formation and also the formation of tracheids with smaller lumen area. In both years a bimodal pattern of stem radial increment was registered by band dendrometers with two periods of increment: one in spring and another in autumn. The xylem anatomy study suggests that the autumnal increment period corresponded mostly to stem rehydration, since the differentiation of new xylem cells by the cambium was not observed.

Conclusion

Maritime pine cambial activity appears to be under a double climatic control: temperature influences cambial onset and water availability growth cessation.  相似文献   
105.
Cortisol may be useful as a marker in predicting how an animal will respond to stressful stimuli, thus providing information on animal's temperament. To quantify the level of transport stress and the effect of temperament on the adrenocortical response, the change in circulating cortisol levels was evaluated in 84 healthy experienced thoroughbred and crossbred stallions, mean age 11.4 ± 4.5 years old, after road transport in a commercial trailer (6 horses per load, stocking density: 2 m2/horse), over mean distances of 210 ± 11.8 km for about 3 hours. Several experienced caretakers were asked to complete 2 questionnaires, one that used a 5-point scale to subjectively evaluate temperament and another that used a 3-point scale to assess tendencies in response to ordinary care and daily management. The scores for the latter were defined as follows: a score of 1 indicated that the horse had never or rarely troubled the caretaker during management, 2 occasionally, and 3 usually. On this basis, the subjects were distinguished between calm and nervous stallions. Blood samples were taken same daytime (8.00 am), in single box, immediately before loading, then after transport and unloading. Serum cortisol concentrations were analyzed in duplicate by immunoenzymatic assay. Compared with basal levels, cortisol increases were observed in both calm (P < 0.001) and nervous (P < 0.05) stallions after transport. Repeated-measures analysis of variance showed significant effects of transport on cortisol changes (P < 0.001). Nervous subjects showed lower (P < 0.01) cortisol levels than did calm subjects after transport, and basal cortisol levels did not differ between calm and nervous subjects. No significant differences (P > 0.05) between different age, breed, and orientation were detected.The results showed that temperament could influence the adrenocortical responses of stallions after short-term transportation. The presence of the same staff for handling, loading, confinement, and unloading, the same veterinarian taking all blood samples, and the presence of cospecifics did not reduce the response to short transport stress both in calm and nervous stallions already accustomed to transport. Lower cortisol concentrations in nervous subjects might be because of failure of the adrenal cortex to respond normally to transport stress. Moreover, signs of transport stress were less pronounced in nervous stallions.  相似文献   
106.
alpha(1)-Acid glycoprotein modulates apoptosis in bovine monocytes   总被引:1,自引:0,他引:1  
alpha(1)-Acid glycoprotein (AGP, orosomucoid) is a normal constituent of bovine blood. AGP is an immunocalin, a binding protein that can also exert several immunomodulatory functions. In this paper we investigated the effect of bovine alpha(1)-acid glycoprotein (boAGP) on spontaneous and staurosporine-induced apoptosis of blood derived monocytes purified using magnetic cell sorting techniques. Bovine AGP was purified from blood following a chromatographic protocol. The homogeneous protein was used to stimulate the cells as well to raise a polyclonal antibody, that was used throughout all the experiments. When monocytes were incubated with high concentrations of boAGP (0.9 mg/ml), similar to those found in bovine plasma during systemic reaction to inflammation, their spontaneous apoptosis rate was suppressed, as determined by caspase-3/7 enzymatic activity assay. Similar results were obtained when apoptosis was induced by adding staurosporine, a potent protein kinase inhibitor. The apoptosis-modulating activity of boAGP was dependent on its concentration, since physiological concentrations of boAGP (0.3 mg/ml) did not exhibit a statistically significative anti-apoptotic activity. We also investigated whether this apoptosis-modulating activity was dependent on the terminal sialic acid residues exposed on the surface of the protein. Enzymatic treatment with neuraminidase, that cleaves terminal sialic acid residues, completely abolished boAGP's anti-apoptotic activity. These results suggest that the protective effect of AGP is likely mediated by its sialic acid terminal groups.  相似文献   
107.
One of the requirements for the forest restoration of soils disturbed by the oil‐exploitation industry is that saplings be able to endure soil‐adverse conditions. In this study, saplings of 20 species susceptible to be used in reforestation programs were evaluated for their ability to grow on substrates derived from soils disturbed by petroleum extractions in the Ecuadorian Amazon. Seeds of each species were planted in germination trays. Once seedlings reached 5 cm in height they were transplanted to plastic bags with three treatment substrates: two derived from petroleum‐exploitation activity (soils from mud and drill cutting cells and from areas surrounding oil wells) and a control soil. Plant survival rate, stem height, and diameter were measured on a weekly basis until 14 weeks after transplantation, when we harvested the plants and also measured plant biomass and calculated the Dickson quality index for each species. Oil‐exploitation by‐product substrates impaired the performance of many saplings, with the substrate from mud and drill cutting cells being the one that most affected plant performance. Only saplings of five native species in the Amazon basin—Apeiba membranaceae, Cedrelinga cateniformis, Inga densiflora, Myroxylon balsamum, and Pouroma cecropiifolia—exhibited high or similar Dickson quality index values in all soil treatments and performed better than the rest. The use of these five species in remediation of soils disturbed by petroleum extraction in the Amazon basin could prove important because of their high potential to adapt to these disturbed sites. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
108.
Brazil is currently the worlds largest producer of papaya (Carica papayaL.), producing fruits for both the domestic market and export. Only fruits from hermaphrodite plants are marketed because they have the necessary commercial characteristics, i.e. they are pear-shaped and have thicker flesh and a smaller internal cavity. Increased papaya yield has been limited mainly by the ratio of female to hermaphrodite (1: 2) plants normally occurring in orchards. This ratio causes great losses to papaya producers and the identification of the sex of seedlings during the nursery stage would be an important advance. In our study random amplified polymorphic DNA (RAPD) analysis was used to differentiate between the sexual forms of three commercial C. papaya cultivars belonging to the Solo group. RAPD assays using the BC210 primer were able to detect hermaphrodites in all of the cultivars tested. The BC210438molecular marker was much better at papaya sex differentiation than other markers described in the literature. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
109.
Summary A method for comparing locations as selection sites based upon their abilities to predict yield and disease reaction over a target region is proposed. The probability of coincidence in selection for a site is defined as the probability for a line selected at the site to be selected at other sites within the region. The probability of divergence in rejection is defined as that associated with regional selection of a line given that is discarded by the site where selection is being conducted. The ideal selection site would maximize the probability of coincidence in selection and minimize the probability of divergence in rejection. The method is illustrated using a set of data from the rice yield nurseries of the International Rice Testing Program for Latin America planted under the rainfed conditions of Central América and México during the period 1978–1984. Five locations were compared for their predictive ability in selecting for the rainfed rice growing region, based on yield and disease reaction. Selection for yield was defined as performance superior to the best check in each location. Selection for disease reaction was based on an index derived from the Standard Evaluation System for Rice for diseases of regional importance. Locations varies 10–15 percent in their selection coincidence with the region for both yield and disease selection criteria applied independently.  相似文献   
110.
Three E-cinnamic acid glycosides, tryptophan, and cyanidin-3-O-beta-D-glucopyranoside were isolated from ripe fruits of the Chilean strawberry Fragaria chiloensis ssp. chiloensis. 1-O-E-Cinnamoyl-beta-D-xylopyranoside, 1-O-E-cinnamoyl-beta-D-rhamnopyranoside, and 1-O-E-cinnamoyl-alpha-xylofuranosyl-(1-->6)-beta-D-glucopyranose are reported for the first time. The cinnamic acid glycosides and aromatic compound patterns in F. chiloensis fruits were determined by high-performance liquid chromatography (HPLC). HPLC analyses of extracts showed that cyanidin-3-O-beta-D-glucopyranoside and free ellagic acid are present in achenes while the E-cinnamoyl derivatives and tryptophan were identified only in the thalamus. The free radical scavenging effect of the fruit extract can be associated with the anthocyanin content.  相似文献   
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