Carbon dynamics in small tropical catchments under preserved forest and cacao agroforestry systems

Agroforestry Systems - Inland waters such as streams that receive carbon from terrestrial landscapes usually have a net heterotrophic metabolism and emit significant amounts of CO2 to the...     

Genetic and functional leaf traits variability of Quercus laurina along an oak diversity gradient in Mexico

The ecological literature has documented the effects of plant hybridization on phenotypic variation, and dominant, intermediate, or novel morphological, chemical and physiological traits in hybrids. It is important to understand the ecological consequences of hybridization by evaluating their impact on phenotypic expression of functional traits. We evaluated the relationship between genetic diversity of Quercus laurina and functional foliar traits along an oak diversity gradient. We selected five study sites that represent an oak diversity gradient where Q. laurina is present. Using chloroplast and nuclear microsatellites, we evaluated genetic diversity, measured functional foliar traits of Q. laurina in each site and assessed the effects of local climate variables on the oak community and functional traits. We found a greater abundance of Q. laurina in all study sites. We did not find a relationship between the number of accompanying red oak species and the population genetic diversity in Q. laurina, but higher genetic diversity was found in all study sites in comparison with European oak species. Sites with more oak species had more variation of foliar functional traits. Our results do not support the hypothesis that predicts higher levels of genetic diversity of Q. laurina in communities with greater oak diversity from the same section, but we demonstrated an increase in the foliar functional traits of Q. laurina associated with oak richness and climate variables. We highlight the need to consider environmental and ecological variables linkages as regulatory mechanisms of the phenotypic plasticity expressed in changes of some functional attributes of oaks.

     

Variable-rate seeding in soybean according to soil attributes related to grain yield

Precision Agriculture - Defining the ideal soybean stand is essential for obtaining maximum grain yield. As a hypothesis of the work, it was questioned whether it is possible to vary seeding...     

Clinical findings related to intramammary infections in meat-producing ewes

The aim of this study was to investigate the relationship between clinical findings and bacterial isolation in milk samples of meat-producing ewes. The study was conducted in 17 commercial flocks and 550 udder halves from suckling Santa Ines ewes. Initially, the clinical examination of the mammary glands and teats was performed by visual inspection and palpation of the teats and udder halves; then a scoring system was devised for all the findings. After that, the strip cup test and the California mastitis test (CMT) were performed. Then, milk samples for somatic cell counts (SCCs) and bacteriological analyses were collected. Staphylococci bacteria were the main etiological agent isolated in the present study. Upon investigation of the correlations between bacterial isolation and the clinical findings, only the presence of teat injury, pendulous udder, and alterations in the palpation of the teat were associated with bacterial isolation. A significant correlation between bacteriologically positive milk samples and CMT and SCC was also found. Thus, some clinical findings appeared as a risk factor for bacteriologically positive milk samples and can be used as a tool in mastitis control programs. However, a complete and extensive diagnosis, an appropriate therapy, and an efficient mastitis control program will require the combination of clinical examination, microbiological tests, and SCC.     

Short-wave solar radiation level willingly tolerated by lactating Holstein cows in an equatorial semi-arid environment

The amount of short-wave solar radiation willingly tolerated by lactating Holstein cows on pasture was determined in an equatorial semi-arid environment. The study was carried out on a dairy farm located in Limoeiro do Norte, CE, northeastern Brazil. The observed behaviours were as follows: grazing, under the sun, under the shade, standing, lying, ruminating, idling and wallowing in the water. The behaviours were recorded using instantaneous scan sampling at regular intervals of 15 min from 0600 to 1800 hours over 5 days. On all sampling days, the meteorological variables, including local short-wave solar radiation (R _S-W, W m^?2), were recorded. The R _S-W data were divided into five levels. The sun exposure was more frequent under low (100 %) and moderately low (97 %) levels, when R _S-W remained below 500 W m^?2. The grazing was more intense under low (100 %) and moderately low (93 %) levels. Above 500 W m^?2, the grazing time significantly decreased (11 %). The cows avoided grazing under high (0 %) and very high (0 %) levels, when R _S-W exceeded 700 W m^?2. The ruminating behaviour was more frequent under high (33 %) and very high (37 %) levels, in which the highest averages of R _S-W were recorded (815 and 958 W m^?2, respectively). The standing posture was more frequent under low (100 %) and moderately low (97 %) levels. Therefore, the critical R _S-W level that motivates cows to stop grazing and seek shade was in the interval between 500 and 700 W m^?2.     

Evaluation of hepatitis E virus infection between different production systems of pigs in Brazil

The objectives of this study were to (1) investigate the occurrence of hepatitis E virus (HEV) in pigs from large-scale and family-scale farms, (2) genetically characterize the strains isolated, and (3) study the pathogenesis of swine HEV infection via immunohistochemistry. A total of 50 pigs from 10 farms in Mato Grosso State, Brazil were divided according to type of production system into either large-scale farms (n?=?5) or family-scale farms (n?=?5). Samples of liver, gallbladder, small and large intestines, bile, and feces from the pigs were analyzed by nested PCR with primers targeting the ORF2 region of HEV and by immunohistochemistry. Of the eight HEV-positive samples from pigs of family-scale farms, phylogenetic analysis revealed that seven of the swine HEV isolates clustered with subtype 3b of genotype 3 and one isolate was categorized with subtype 3 f. The HEV antigen was detected mainly in the small intestine samples from family-scale farms, suggesting an early stage HEV infection. HEV was not detected in the samples of pigs from large-scale farms, reinforcing the need for additional studies to evaluate the risk of transmission of HEV to humans from pigs from family-scale farms in Mato Grosso State.     

Effect of the replacement of Tifton 85 with maniçoba hay on the performance of Morada Nova hair sheep

The use of native and adapted forages is an alternative for sustainable production systems in northeast Brazil. The goal of this study was to evaluate the substitution of Tifton 85 by maniçoba hay on the performance and carcass traits of Morada Nova hair sheep. The 16 lambs that were used in this study initially weighed 19.36?±?1.48 kg, were housed in individual pens, and were slaughtered at 58 days of confinement. The dry matter intake (839.84 g/day and 3.81 % WB) was higher (P?<?0.05) in sheep fed maniçoba hay. The feed conversion was 7.39 for sheep fed maniçoba hay. The empty body weight (21.61 kg) and cold carcass weight (11.40 kg) did not differ (P?>?0.05) between sheep fed different hay types. The replacement of Tifton 85 by maniçoba hay did not influence the loin eye area (cm²) or carcass compactness index (kg/cm). The replacement of Tifton 85 by maniçoba hay in Morada Nova sheep diet did not affect the weight gain or carcass characteristics. The maniçoba hay can be considered a forage resource for feeding sheep in Brazilian semiarid tropics.     

Prevalence of antimicrobial resistance in enteric Escherichia coli from domestic pets and assessment of associated risk markers using a generalized linear mixed model

Antimicrobial resistance (AMR) is a growing global public health problem, which is caused by the use of antimicrobials in both human and animal medical practice. The objectives of the present cross-sectional study were as follows: (1) to determine the prevalence of resistance in Escherichia coli isolated from the feces of pets from the Porto region of Portugal against 19 antimicrobial agents and (2) to assess the individual, clinical and environmental characteristics associated with each pet as risk markers for the AMR of the E. coli isolates.     

Subependymal Reaction Secondary to Choroid Plexus Papilloma in a Horse

Choroid plexus papilloma (CPP) is a rare, benign, intracranial neoplasm. The present report described a choroid plexus papilloma of the fourth ventricle with unusual proliferative reaction of ependymal/subependymal cells in a stallion. A single, soft neoformation, red-gray in color, with an irregular surface, resembling a cauliflower, expanding from the fourth ventricle to the cerebellar peduncles was observed. Microscopically, the neoformation was composed of a single layer of simple cuboidal to columnar epithelium with a well-vascularized papillary-arboriform pattern. Multifocal subependymal aggregates forming rosettes were observed near the mesencephalic aqueduct (MA). Glial-fibrillary-acidic-protein (GFAP) was markedly positive only in the neuropil adjacent to the proliferative areas of the MA. Ependymal/subependymal reactions secondary to CPP have never been described in equine or human neuropathology. The capabilities of ependymal cells to regenerate and eventually proliferate are controversial and unclear and, thus, require additional investigation to understand the adaptive mechanisms of this rare pathogenic condition.     

Effect of Breeding Activity on the Microflora of the External Genitalia and in the Semen of Stallions,and the Relationship Between Micro‐organisms on the Skin and on the External Genitalia

A possible role of breeding activities in the composition of the microbial population in stallions' external genitalia (EG) and the relationship between micro‐organisms colonizing the skin of the abdomen and the ones colonizing the EG have not been studied. In experiment 1, EG microbiological samples were collected from 41 stallions used for both natural cover and semen collection (BST) and from 18 non‐breeding stallions (NBST). A higher (p < 0.05) frequency of isolation of potentially pathogenic species was found for BST. Age did not influence number of micro‐organism species isolated both in BST and NBST. In experiment 2, the microbial content of the EG and semen was compared in 23 BST. Most micro‐organisms isolated from the EG were present in semen, albeit with a numerically lower prevalence. In 7 stallions, six microbial species isolated from semen were absent from the EG cultures, suggesting contamination by the operator. In experiment 3, a numerically higher number of micro‐organism species was isolated from the EG of 31 stallions, than from their skin of the ventral abdomen in contact with the penis or from the skin of the thorax. With the sole exception of Escherichia coli, potentially pathogenic bacteria were only isolated from the EG but not from the skin. Results suggest that breeding activity increased the number of species colonizing the EG; most species isolated from the EG were also found in semen even if with a lower frequency, and additional semen contamination seemed to occur during its manipulation. Many micro‐organism species of the skin were also isolated from the penis, but independently of being or not in contact with the penis, skin did not seem to provide an adequate environment for the growth of potentially pathogenic bacteria that were isolated from EG, with the sole exception for E. coli.