Lipid droplets in clusters negatively affect Bos indicus embryos during cryopreservation

Embryo transfer using cryopreserved B. indicus embryos results in low pregnancy rates. The low viability of B. indicus embryos is likely a result of their low freezability relative to embryos from other species, notably B. taurus. Freezability is probably related to the quantity of lipid droplets in the embryonic cells. However, the mechanism underlying this association is unknown. Using multiphoton and transmission electron microscopy, the proportion, volume, morphology and composition of lipid droplets in fresh and cryopreserved B. indicus and B. taurus embryos were studied. B. indicus embryos have more droplets than B. taurus and a greater percentage of lipid droplets in clusters (34% vs. 24%; p < 0.05). Also, B. indicus individual droplets are of greater volume than those of B. taurus (47 μm³ vs. 34 μm³; p < 0.05). After freezing, the percentage of clusters decreased in B. indicus (11% vs. 5%; p < 0.05), while in B. taurus they increased (2% vs. 7%; p < 0.05). Freezing influenced the lipid droplet morphology, increasing the number of cracked droplets in B. indicus embryos (33% fresh vs. 62% frozen; p < 0.05), but not in B. taurus embryos (35% fresh vs. 34% frozen; ns). Regarding composition, saturated lipid droplets prevail in B. indicus embryos, contrary to B. taurus embryos. We observed differences in lipid droplet organization, proportion, volume, morphology and composition between B. indicus and B. taurus embryos which are altered in opposite directions following freezing.     

Patterns of dispersal of hawksbill turtles from the Cuban shelf inform scale of conservation and management

Conserving and managing populations of marine vertebrates can be complex when they occupy the waters of multiple nations, crossing heterogeneous legal and management landscapes. Hawksbill turtles (Eretmochelys imbricata) are subject to varying levels of use in Caribbean countries and their conservation and management is complicated by the extent to which they are a ‘shared’ resource. In 1997 and 2000, Cuba attempted to ‘downlist’ hawksbills from Cuban waters to CITES Appendix II to allow limited international trade. The research on movement and dispersal of hawksbills reported here was undertaken to better inform discussion about the impacts of their harvest. Flipper tagging and satellite tracking demonstrate that the majority of study turtles remained in Cuban territorial waters. Of 1170 hawksbills tagged (525 adults and 606 juveniles), 12% (n = 143) were recaptured. All recaptured adults (n = 16 males, 38 nesting females and 30 adult females in-water) were in Cuban waters. Of the 59 juveniles recaptured, only four recaptures were outside Cuban waters (Nicaragua = 2, Colombia = 1, USA = 1). Fourteen hawksbills tagged in the waters of other nations were recaptured in Cuban waters. We also satellite tracked 21 turtles (one adult male, ten nesting females and ten non-nesting adult females), of which five tags failed, 11 stayed in Cuban waters for the duration of transmissions (1–809 days) and five foraged in the waters of other nations (Mexico n = 1 an adult female; Honduras n = 2, both post-nesting turtles; Colombia n = 1 an adult female; and the eastern Lesser Antilles n = 1, an adult male), with differences for nesting and non-nesting turtles. Our results, demonstrating extended site fidelity within Cuban waters, suggest that strengthening national management within national jurisdictions that host hawksbill turtles is fundamental to improving regional conservation as a whole.     

Transpiration of table grape (Vitis vinifera L.) trained on an overhead trellis system under netting

The quantification of transpiration and corresponding basal crop coefficients is crucial for appropriate irrigation scheduling of drip-irrigated crops. Besides basal crop coefficients already published, there is the announcing need for setting values for the new growing practices such as cropping under netting. In this paper, measurements of unstressed table grape transpiration and basal crop coefficients under netting have been taken. Vineyards of two seedless cultivars (Crimson and Autumn Royal) were trained on an overhead trellis system which permitted the ground cover to reach values up to 90 %. Two campaigns of mid-season measurements were performed using one of the heat pulse techniques available (that known as the T _max approach). Obtained values for average seasonal daily transpiration ranged between 3.9 and 4.4 mm day^?1, for both cultivars, depending on the period considered. Weekly averages of the basal crop coefficients, from mid-May to end-September, ranged from 0.47 to 0.87. A polynomial equation was fit to the measured basal crop coefficients as a function of fraction of thermal units. After further validation for other cultivars with different cumulative thermal requirements, this equation could be considered helpful for farmers as a practical estimate of the table grape basal crop coefficient under the netting.     

EFFECTS OF CONVERTING FOREST TO AVOCADO ORCHARDS ON TOPSOIL PROPERTIES IN THE TRANS‐MEXICAN VOLCANIC SYSTEM,MEXICO

In the present work, land cover and land use changes between 2003 and 2008 were assessed in the Cupatitzio River sub‐basin located in the Trans‐Mexican Volcanic System and Balsas Depression in Mexico. The effects of land cover conversion from temperate forest to avocado orchards on soil properties were determined. Land cover and land use databases were built for the years 1975, 2003, and 2008 using available cartographic information and interpretation of panchromatic SPOT images for the year 2008. Additionally, soil sampling was carried out in 16 representative sites in the higher parts of the sub‐basin, where avocado plantation dynamics have caused important changes in areas covered by temperate forests. Results show that (i) temperate coniferous and tropical low deciduous forests were reduced at an annual rate of 0·9 per cent (1, 001 ha y⁻¹) between 1975 and 2008; (ii) cropland areas expanded at an annual rate of 0·7 per cent between 1975 and 2008, representing a growth of 553 ha y⁻¹; (iii) wet soil aggregate stability, mechanical resistance to penetration and nitrate (N‐NO₃) concentration in the topsoil layer of Andosols were significantly affected by land use conversion to avocado orchards. Other soil properties such as organic matter, interchangeable K, and available P showed degradation tendencies. These results suggest the importance of implementing strategies for mitigating the accelerated process of transformation and degradation of natural resources in the Cupatitzio River sub‐basin. The implementation of programs for deforestation reduction should be a priority in the restoration strategy. Copyright © 2012 John Wiley & Sons, Ltd.     

A field investigation of the use of the pedometer for the early detection of lameness in cattle

The efficacy of the pedometer to predict lameness earlier than the appearance of the clinical signs in a herd of dairy cows was investigated by correlating pedometric activity (PA) with clinical cases of lameness. The computer program was set to identify cows with a reduction of 5% or more in PA compared with their own previous 10 days average; these animals were then examined for clinical lameness. At the same time, every lame cow was checked to see if and when its PA was reduced. Forty-six cows showed a reduced PA; 38 cases of lameness were identified by either a reduction in PA or clinical observation; of these, 21 lame cows (45.7%) showed a reduction in PA of 5% or more, 7 to 10 days prior to the appearance of clinical signs. This cohort comprised 55.3% of the lame cows. In 92% of the lame cows identified by PA, the decrease was above 15%.     

Survey of Neospora caninum infection by nested PCR in aborted fetuses from dairy farms in Aguascalientes, Mexico

The aim of this study was to determine by nested PCR probe the presence of Neospora caninum in fetal brain tissue from aborted dairy fetuses in Aguascalientes, a state in the central part of Mexico. Forty-four fetal brains from eight dairy farms were analyzed using single tube nested PCR probe with primers NF1, NS2, NR1 and SR1, with histopathology as the reference technique. From the 44 bovine fetuses studied, 35 (80%) were diagnosed as being infected by N. caninum using PCR probe and 20 (45%) were considered positive by histopathology, because they had lesions suggestive of bovine neosporosis. Fair agreement was observed (31%) between both probes. The age of aborting cows ranged from 1.6 to 2.9-year-old in 17 (49%) of the positive cases diagnosed by PCR. Gestational ages of aborted fetuses ranged from <3 to 9 months, with average of 5.6 months, and no statistical significant difference was observed when ages of infected and no infected fetuses were compared (P > 0.05). The frequency of N. caninum positive cases observed could be considered to be higher than other areas of Mexico and other countries.     

Effect of molecular structure of phenolic families as hydroxycinnamic acids and catechins on their antioxidant effectiveness in minced fish muscle

The antioxidant effectiveness of two different families of phenolic compounds, hydroxycinnamic acids and catechins, added as a power (0.001% w/w) to chilled minced horse mackerel muscle was evaluated. Caffeic acid, chlorogenic acid, o-coumaric acid, and ferulic acid were selected as hydroxycinnamic acids with similar molecular structures. Commercial catechins with different numbers of hydroxylic groups, including catechin, gallocatechin, catechin gallate, and gallocatechin gallate, were also tested. The effectiveness found was individually discussed for each family as a function of the molecular structure. The capacity of hydroxycinnamic acids for donating electrons seems to play the most significant role for retarding the development of rancidity in fish muscle. Conversely, the properties related to the ability for chelating metals and the distribution between oily and aqueous phases were not correlated with the inhibitory activities. Among hydroxycinnamic acids, the results highlighted the potent antioxidant activity of 10 ppm caffeic acid in inhibiting lipid oxidation in fish muscle. Its antioxidant efficacy was similar to that of propyl gallate. Among catechins, catechin showed the highest antioxidant activity. There was an increment of efficacy in fish muscle using concentrations ranging between 10 and 100 ppm of both caffeic acid and catechin.     

Changes in color and odorant compounds during oxidative aging of Pedro Ximenez sweet wines

Pedro Ximenez sweet wines obtained following the typical criaderas and solera method for sherry wines and subjected to oxidative aging for 0, 1.3, 4.2, 7.0, or 11.5 years were studied in terms of color and aroma fraction by using the CIELab method and gas chromatography, respectively. The parameters defining the CIELab color space (a*, b*, and L*) were subjected to a multiple-range test (p<0.05) that allowed discrimination of the five wine aging levels studied into five uniform groups according to aging time. The aroma fraction was found to include 15 active odorant compounds with OAV > 1 that enriched the wines with fruity, fatty, floral, and balsamic notes during the aging process. The changes in color parameters and active odorants were not linearly related to aging time, being especially marked during the first 1.3 years and then less substantial up to the 7 years, the oldest wines exhibiting sensorial properties markedly departing from all others. For the wines aged over 1.3 years (minimum aging), 2,3-butanedione, linalool, and decanal can be used as reliable fingerprints of the older wines' quality.     

Main antimicrobial compounds in table olives

The inhibitors involved in the lactic acid fermentation of table olives were investigated in aseptic olive brines of the Manzanilla and Gordal varieties. Phenolic and oleosidic compounds in these brines were identified by high-performance liquid chromatography with ultraviolet and electrospray ionization mass spectrometry detection, and several substances were also characterized by nuclear magnetic resonance. Among these compounds, the dialdehydic form of decarboxymethyl elenolic acid linked to hydroxytyrosol showed the strongest antilactic acid bacteria activity, and its presence in brines could explain the growth inhibition of these microorganisms during olive fermentation. However, it was found that the dialdehydic form of decarboxymethyl elenolic acid, identified for the first time in table olives, and an isomer of oleoside 11-methyl ester were also effective against Lactobacillus pentosus and can, therefore, contribute to the antimicrobial activity of olive brines. It must also be stressed that the three new inhibitors discovered in table olive brines exerted a more potent antibacterial activity than the well-studied oleuropein and hydroxytyrosol.