Herd characteristics and management practices associated with bulk tank milk quality of dairy herds in southeastern Brazil

Tropical Animal Health and Production - This study identified the association of management practices and herd characteristics with milk quality of bulk tanks in southeastern, Brazil. Milk samples...     

Relationships between internal ethylene and optical reflectance in ripening ‘Antonovka’ apples grown under sunlit and shaded conditions

The feasibility of non-destructive estimation of internal ethylene concentration (IEC) in apple fruit via fruit reflectance using recently developed approaches and a fiber-optics reflectometer was investigated. The relationships between IEC and fruit reflectance in the 400–800 nm range were studied in stored apple (Malus × domestica Borkh., cv. Antonovka) fruit. A strong correlation between IEC and optical reflectance spectra taken from sunlit surfaces of the fruit was detected whereas reflectance of the shaded fruit surface showed a weak correlation with IEC. The increase of the reflectance in the red occurred along with IEC build-up during ripening resulting a strong (r² > 0.80) correlation. By contrast, reflectance in the blue-green part of the spectrum remained low and was negatively (r² ≈ 0.65) correlated with IEC. These observations are consistent with the phenomenon of degradation of chlorophylls which often occurs in parallel with the retention of carotenoids in ripening apple skin. As a result, IEC showed a significant correlation (r² > 0.69; P < 0.001) with the index based on reflectances in the red and blue-green regions of the spectrum (R₆₇₈ ? R₄₈₀)/R₈₀₀. The effects of strong solar light on the relationships between IEC and fruit reflectance are considered. The possibilities and limitations of a non-destructive reflectance-based assay of IEC in apple fruit are discussed.     

Antiviral evaluation of plants from Brazilian Atlantic Tropical Forest

The antiviral activity of six medicinal plants from Brazilian Atlantic Tropical Forest was investigated against two viruses: herpes simplex virus type 1 (HSV-1) and poliovirus type 2 (PV-2). Cuphea carthagenensis and Tillandsia usneoides extracts showed the best antiherpes activity. T. usneoides dichloromethane, ethyl acetate and n-butanol extracts, and Lippia alba n-butanol extract showed inhibition of HSV-1, strain 29R/acyclovir resistant. In addition, only L. alba ethyl acetate extract showed antipoliovirus activity. These results corroborate that medicinal plants can be a rich source of potential antiviral compounds.     

Factors affecting the dynamics of the population of Fagus crenata in the Takakuma Mountains, the southern limit of its distribution area

The refugee population of Fagus crenata in the Takakuma Mountains, Kyushu, Japan, represents the southern limit of this species' distribution area. Because this population is the most exposed to the global warming effect, records of this population are likely to provide useful information on the response of this species to global warming. The aim of this study was to record the present status of this valuable population, enabling judgment of its sustainability. The density of successive F. crenata trees and saplings was low regardless of the coverage of dwarf bamboo. Moreover, the proportion of empty nuts observed was considerably high, suggesting to be the likely major factor limiting recruitment of saplings or successors in this population. Radial growth of F. crenata was shown to have been decreasing for the past 50 years, and there was a significantly negative correlation with the warmth index. The decreasing growth rate and poor regenerative ability caused by the high proportion of empty nuts suggest the possibility that this population will degrade further in the future, possibly being replaced by shrubs and small tree species.     

Neurohistologic and ultrastructural lesions in cattle experimentally intoxicated with the plant Prosopis juliflora

Intoxication by pods of Prosopis juliflora (mesquite beans) causes an impairment of cranial nerve function in cattle and goats. In goats, vacuolation of neurons in the trigeminal motor nuclei has been reported. To study the lesions in cattle caused by consumption of P. juliflora pods and dry ground pods, eight 6- to 12-month-old male cattle were divided into 4 groups: group 1 was fed a ration containing 50% of pods; groups 2 and 3 received a ration containing 50 and 75% of dry ground pods, respectively; group 4 was the control. After 200 days, all cattle were killed and sampled for histologic evaluation. Samples of the trigeminal motor nucleus were examined by electron microscopy. All cattle from groups 1, 2, and 3 showed clinical signs resulting from impaired function of cranial nerves V, IX, X, and XII, starting 45-75 days after consumption of the plant. The main histologic lesions were vacuolation and loss of neurons in trigeminal motor nuclei and other motor cranial nerve nuclei with Wallerian-like degeneration in the cranial nerves. Mild denervation atrophy was observed in the masseter and other masticatory muscles. On electron microscopy, neurons of the trigeminal nuclei had markedly swollen mitochondria, with the mitochondrial cristae displaced peripherally, disoriented and disintegrating. Intoxication by P. juliflora seems to have a novel pathogenesis, characterized by a selective, primary, chronic, and progressive injury to mitochondria of neurons of the trigeminal and other cranial nerve nuclei. Cranial nerve degeneration and denervation atrophy of the muscles occurs as a consequence of the neuronal lesion.     

Productivity of single-grip harvesters in clear-cutting operations in the northern European part of Russia

A field-based study was carried out to broaden our knowledge of fully mechanized cut-to-length harvesting productivity in naturally grown forests in the northern European part of Russia (NEPR). The recorded data comprised 38 midsized single-grip harvesters (JD 1270D) in clear-cutting operations in the Karelia, Komi, Vologda, Leningrad, Tver, and Kirov regions in NEPR, 4.3 million felled trees, and 1.4 million m³ u.b. (under bark) of processed timber. Harvesting operations were conducted in forest stands composed of spruce (48% on average), pine (19%), birch (22%), and aspen (11%), with an average stem volume 0.31 m³ u.b. The cut-to-length harvesters produced from 4.3 to 14.9 m³ u.b./productive machine hour (PMH) and 16.0–49.5 m³ u.b./stem processing machine hour (S _proc MH). A machine evaluation analysis and a regression analysis were used to formulate models for predicting cutting productivity of modern single-grip harvester. The regression models were developed to estimate the productivity of the harvesters in the regions taking into account two significant factors influencing the productivity: the stem volume and tree species of the felled trees. Productivity/cubic meter u.b. of processed timber/PMH was calculated according to stem volume and tree species distributions in most forest-covered NEPR regions. Further research is suggested to improve the developed productivity models and to allow prediction of system performance over a broad range of stand and site conditions.     

N -ethyl- N -nitrosourea induces retinal photoreceptor damage in adult rats

Seven-week-old male Lewis rats received a single intraperitoneal injection of N-ethyl-N-nitrosourea (ENU) (100, 200, 400 or 600 mg/kg), and retinal damage was evaluated 7 days after the treatment. Sequential morphological features of the retina and retinal DNA damage, as determined by a TUNEL assay and phospho-histone H2A.X (γ-H2AX), were analyzed 3, 6, 12, 24 and 72 hr, 7 days, and/or 30 days after 400 mg/kg ENU treatment. Activation of the nuclear enzyme poly (ADP-ribose) polymerase (PARP) was analyzed immunohistochemically by poly (ADP-ribose) (PAR) expression in response to DNA damage of the retina. All rats that received ≥ 400 mg/kg of ENU developed retinal degeneration characterized by the loss of photoreceptor cells in both the central and peripheral retina within 7 days. In the 400 mg/kg ENU-treated rats, TUNEL-positive signals were only located in the photoreceptor cells and peaked 24 hr after ENU treatment. The γ-H2AX signals in inner retinal cells appeared at 24 hr and peaked at 72 hr after ENU treatment, and the PAR signals selectively located in the photoreceptor cell nuclei appeared at 12 hr and peaked at 24 hr after ENU treatment. However, degeneration was restricted to photoreceptor cells, and no degenerative changes in inner retinal cells were seen at any time points. Retinal thickness and the photoreceptor cell ratio in the central and peripheral retina were significantly decreased, and the retinal damage ratio was significantly increased 7 days after ENU treatment. In conclusion, ENU induced retinal degeneration in adult rats that was characterized by photoreceptor cell apoptosis through PARP activity.     

Edible coatings containing chitosan and moderate modified atmospheres maintain quality and enhance phytochemicals of carrot sticks

Carrot sticks are increasingly in demand as ready-to-eat products, with a major quality problem in the development of white discoloration. Modified atmosphere packaging (MAP) and edible coating have been proposed as postharvest treatments to maintain quality and prolong shelf-life. The combined application of an edible coating containing 5 mL L^?1 of chitosan under two different MAP conditions (10 kPa O₂ + 10 kPa CO₂ in Pack A and 2 kPa O₂ + 15–25 kPa CO₂ in Pack B) over 12 d at 4 °C was studied. Respiration rate, microbial and sensory qualities as well as the contents of vitamin C, carotenoids and phenolics of coated and uncoated carrot sticks were evaluated. The use of the edible coating containing chitosan preserved the overall visual quality and reduced surface whiteness during storage. Microbial populations were very low and not influenced by coating or MAP. Edible coating increased respiration rates of carrot sticks, although this was only noticeable in the package with the less permeable film (Pack B). Vitamin C and carotenoids decreased during storage particularly in coated carrot sticks. In contrast, the content of total phenolics markedly increased in coated carrot sticks stored under moderate O₂ and CO₂ levels, while it was controlled under low O₂ and high CO₂ levels. The combined application of edible coating containing chitosan and moderate O₂ and CO₂ levels maintained quality and enhanced phenolic content in carrot sticks.     

Efficacies of liposome-encapsulated enrofloxacin against Staphylococcus aureus infection in Anatolian shepherd dog monocytes in vitro

The aim of this study was to evaluate the intracellular activity of two types of liposome-encapsulated enrofloxacin (LE) compared with free enrofloxacin and non-treated control against Staphylococcus aureus, phagocytosed by monocytes in healthy Anatolian Shepherd dogs. Enrofloxacin was encapsulated with two different types of liposome in multilamellar large vesicles (MLV). Type A MLV were composed of 15 mg phosphatidylcholine and 35 mg cholesterol, Type B MLV were composed of phosphatidylcholine, cholesterol and enrofloxacin in a molar ratio of 1:1:1. Intracellular activity was estimated by comparing the numbers of bacteria surviving intracellularly in monocytes exposed to free enrofloxacin and LE for 4 h at the doses of 0.25, 0.5 and 1 microg/ml, with those surviving intracellularly in untreated control monocytes. All three forms of enrofloxacin (free, Type A and B liposomes) increased the intracellular killing of S. aureus in a concentration dependent manner. Comparison of 1 microg/ml Type B LE revealed that killing activity was significantly higher than those of other concentrations. The results showed that LE was superior in reducing the number of intracellularly located bacteria compared to the free drug and control. The beneficial effect of liposomal encapsulation is presumably due to the fact that both liposomes and bacteria are localized at the same spot in phagocytic cells.     

Genetic Structure of Field Populations of Begomoviruses and of Their Vector Bemisia tabaci in Pakistan

ABSTRACT The genetic structure of field populations of begomoviruses and their whitefly vector Bemisia tabaci in Pakistan was analyzed. Begomoviruses and B. tabaci populations were sampled from different crops and weeds in different locations in Punjab and Sindh provinces, in areas where cotton leaf curl disease (CLCuD) occurs or does not occur. Phylogenetic analysis based on nucleotide sequences of the intergenic region in the viral DNA-A provided evidence of two clusters of isolates: viruses isolated from species in the family Malvaceae, and viruses isolated from other dicotyledon families. Analysis of the capsid protein (CP) open reading frame grouped isolates into three geographical clusters, corresponding to isolates collected in Punjab, Sindh, or both provinces. Random amplified polymorphic DNA analyses of the B. tabaci population showed that intrapopulation diversity was high at both the local and regional scales. Sequence analysis of the mitocondrial cytochrome oxydase I (mt COI) gene showed that the B. tabaci population was structured into at least three genetic lineages corresponding to the previously described Indian, Southeast Asian, and Mediterranean-African clades. The Indian clade was present only in Punjab, the Mediterranean-African only in Sindh, and the Southeast Asian in both provinces. B. tabaci haplotypes of the Indian clade were found only in the Punjab, where CLCuD occurs. Hence, the geographical distribution of virus and vector genotypes may be correlated, because similar phylogenetic relationships were detected for the viral CP and the vector mt COI genes.