Corpus luteum vascularization during the maternal recognition of pregnancy in llamas (Lama glama)

The aim of this study was to characterize corpus luteum vascularization and its association with plasma progesterone concentration in early stages of pregnancy, when maternal recognition of pregnancy is expected to occur. In all animals, both plasma progesterone concentration and corpus luteum vascularization increased from Day 6 to Day 8 post-mating and afterwards in non-pregnant llamas they started to decrease to reach basal levels around Days 12 to 14 post-mating, while in pregnant animals, both variables remained elevated until the end of the study. A lineal positive relationship between corpus luteum vascularization and plasma progesterone concentration was observed in pregnant (r² = .46, p < .0001) and non-pregnant llamas (r² = .66, p < .0001). Pregnant animals showed higher plasma progesterone concentration and corpus luteum vascularization than the non-pregnant ones from Day 12 post-mating until the end of the study (p ˂ .05 and p ˂ .01, respectively). These results suggest that maternal recognition of pregnancy should occur before Day 12 post-mating in order to expand luteal lifespan, maintaining corpus luteum vascularization and progesterone production. Also, the assessment of CL vascularization area could be a useful and non-invasive method for early pregnancy diagnosis due to its association with plasma progesterone concentration.     

Correlation between carcass condemnations in slaughterhouses and official notifications of cattle testing positive for tuberculosis

Tropical Animal Health and Production - The objective of this study was to analyze the correlation between condemnations in slaughterhouses situated in Minas Gerais State and notifications to the...     

Early detection of Neophysopella tropicalis in grapevine leaves and on spore traps by qPCR

Neophysopella tropicalis, one of the causal agents of Asian grapevine leaf rust (AGLR), can cause severe epidemics in Brazil that lead to yield losses in commercial vineyards. An early detection of the pathogen by air sampling of urediniospores on spore traps or in symptomless leaves would be valuable to multiple studies, such as epidemics modelling, risk forecasting, monitoring of pathogen introductions in rust-free areas, and predicting the beginning of epidemics. This study developed a quantitative PCR (qPCR) protocol to quantify N. tropicalis urediniospores attached to adhesive tapes and in grapevine leaves before symptom appearance. A specific primer pair was designed based on the internal transcribed spacer (ITS) sequence region of the AGLR pathogen. Standard amplification curves using genomic DNA from urediniospores of N. tropicalis and from urediniospores attached to adhesive tapes were established. Grapevine leaves inoculated with N. tropicalis were collected at 2, 5, and 7 days postinoculation (dpi). One primer pair (580F/720R) amplified a 140 bp product in all AGLR isolates but did not amplify products of other rust genera, such as Phakopsora, Puccinia, Hemileia, Tranzschelia, Cerotelium, and Coleosporium. As little as 0.1 pg DNA and 10 urediniospores of N. tropicalis attached to adhesive tapes could be detected. qPCR enabled the detection of the pathogen as early as 2 dpi, before symptom appearance. This method can be used to monitor N. tropicalis inoculum in grapevine-growing areas and to quantify symptomless infections of the AGLR pathogen.     

Lethal and sublethal effects of chemical constituents from essential oils on Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae: Bruchinae) in cowpea stored grains

Journal of Plant Diseases and Protection - The recent use of essential oils has been considered an important approach in pest management programs for stored products. Regarding essential oils, it...     

Nanoparticles in the management of brown eye spot in coffee

European Journal of Plant Pathology - Brown eye spot (Cercospora coffeicola) is one of the main diseases of coffee (Coffea arabica L.) and represents a serious phytosanitary problem for the crop....     

In situ detection of tree root distribution and biomass by multi-electrode resistivity imaging

Traditional methods for studying tree roots are destructive and labor intensive, but available nondestructive techniques are applicable only to small scale studies or are strongly limited by soil conditions and root size. Soil electrical resistivity measured by geoelectrical methods has the potential to detect belowground plant structures, but quantitative relationships of these measurements with root traits have not been assessed. We tested the ability of two-dimensional (2-D) DC resistivity tomography to detect the spatial variability of roots and to quantify their biomass in a tree stand. A high-resolution resistivity tomogram was generated along a 11.75 m transect under an Alnus glutinosa (L.) Gaertn. stand based on an alpha-Wenner configuration with 48 electrodes spaced 0.25 m apart. Data were processed by a 2-D finite-element inversion algorithm, and corrected for soil temperature. Data acquisition, inversion and imaging were completed in the field within 60 min. Root dry mass per unit soil volume (root mass density, RMD) was measured destructively on soil samples collected to a depth of 1.05 m. Soil sand, silt, clay and organic matter contents, electrical conductivity, water content and pH were measured on a subset of samples. The spatial pattern of soil resistivity closely matched the spatial distribution of RMD. Multiple linear regression showed that only RMD and soil water content were related to soil resistivity along the transect. Regression analysis of RMD against soil resistivity revealed a highly significant logistic relationship (n = 97), which was confirmed on a separate dataset (n = 67), showing that soil resistivity was quantitatively related to belowground tree root biomass. This relationship provides a basis for developing quick nondestructive methods for detecting root distribution and quantifying root biomass, as well as for optimizing sampling strategies for studying root-driven phenomena.     

Serological and pathogenic characterization of Erysipelothrix rhusiopathiae isolates from tonsils of slaughter pigs in Indonesia

Erysipelothrix rhusiopathiae was isolated from tonsils of 245 (35.7%) of 687 apparently healthy slaughter pigs in Indonesia during the period of June 1987 to February 1988. A total of 150 of the 245 E. rhusiopathiae isolated could be serotyped within the 22 recognized serotypes. Serotype 2 was most prevalent with 23.7%, followed by Serotypes 11, 12, 1a, 5 and 6 representing 7.3, 5.3, 4.9, 4.9 and 4.1% of the isolates, respectively. The nine other serotypes (Serotypes 1b, 3, 4, 8, 9, 10, 13, 19 and 22) combined to make up 11.0% of the isolates. Antibiotic-resistant strains were not found. Of 86 selected isolates belonging to various serotypes, 76 (88.4%) were highly virulent for mice (LD50 less than 10(3.0) colony-forming units). In swine, 40 (51.2%) of 78 isolates induced local or generalized urticarial lesions after intradermal inoculation, and the remaining 38 isolates induced no clinical signs. Of 76 isolates used for challenge in the cross-protection study, 29 (38.2%) killed greater than 40% of mice immunized with an erysipelas bacterin marketed in Indonesia. A tendency to be refractory to the bacterin-induced immunity was observed in some isolates of various serotypes, but this characteristic was not consistent.     

Early luteal development in Santa Inês ewes superovulated with reduced doses of porcine follicle‐stimulating hormone

The aim was to compare the early luteal development in ewes superovulated with different doses of pFSH. Twenty‐nine Santa Inês ewes received a progesterone device (CIDR®) for 8 days. Gonadotrophic treatment started on Day 6: G200 (control, n = 9, 200 mg); G133 (n = 10, 133 mg); and G100 (n = 10, 100 mg of pFSH). On Day 6, all females received eCG (300 IU). B‐mode and spectral Doppler ultrasonography were performed daily during the early luteal phase (Days 11–15) to monitor the development of corpora lutea (CLs; dimensions) and ovarian arteries indices. CLs were also classified as normal or prematurely regressed (PRCL) on Day 15 by videolaparoscopy. Ewes from G100 and G133 showed gradual increase in luteal diameter during the early luteal phase (p < 0.001), whereas G200 animals presented increase from Day 11 to Day 13, and then decrease on Days 14 and 15 (p < 0.001). The G200 females showed greater percentage of PRCL (45.20%) than those of the other groups (p < 0.001). The normal CLs number was greater in G100 than in G133 (p = 0.04), while the PRCL number was greater in G200 than in the other groups (p = 0.03). Resistive index (RI) was greater in G200 than in G100 (p = 0.02). RI was lower in Day 12 than Day 15 (p = 0.02). Pulsatility index (PI) was greater on Days 14 and 15 (p < 0.01). In conclusion, the lowest dose of pFSH (100 mg) can be considered sufficient for an efficient superovulatory response in sheep, producing better CLs development dynamic in early luteal phase and ovarian blood perfusion and smaller number of PRCL than the traditional (200 mg) pFSH dose.     

Variance component estimations for race performance of thoroughbred horses in Brazil by random regression model

A total of 306,698 racing performance data recorded between 1992 and 2002 from 25495 Brazilian Thoroughbred horses was analyzed to estimate the variance components using the Random Regression Model (RRM) compared to the Classical Repeatability Animal Model (CRAM). The performance was evaluated using the race time (in seconds) to run distances of 1000, 1100, 1200, 1300, 1400, 1500 or 1600 meters. The pedigree of each horse was extended as far as possible, with a total of 36,659 animals. The simple correlation between Breeding Value (BV) for the race time estimated by both procedures was high (r = 0.963) when the data were expressed at the mean level of all distances. However, with the RRM it was possible to estimate the genetic parameters and the BV of all animals at the trajectory of each one of the seven distances. Also, results clearly showed that a single BV estimated by CRAM, is neither an adequate nor a sufficient indicator for the selection of the best horses throughout the trajectory of distance performance. We concluded that the RRM procedure is highly recommended for the evaluation of racehorse performance.