Pedigree analysis of Czech Holstein calves with schistosoma reflexum

<p>Abstract</p> <p>Background</p> <p>Schistosoma reflexum (SR) is congenital syndrome briefly characterized by visceral eventration, severe dorsoflexion and ankylosis of the spine and arthrogryposis. A genetic etiology has been proposed, but conclusive evidence has not yet been provided.</p> <p>Methods</p> <p>Pedigree analysis was carried out in 29 cases of SR in Czech Holsteins and Holstein crosses. Genetic relationship was evaluated and inbreeding coefficients calculated. Pedigrees of 15 Czech Holsteins fathering non-SR affected calves were used for comparison.</p> <p>Results</p> <p>Twenty-one cases occurred in one pedigree founded by three sires while three SR calves occurred in another pedigree with a common grandfather. The sex ratio between affected males and females was 11:6. Affected calves shared common ancestors different from those shared by the unaffected calves. The inbreeding coefficient in the SR affected calves was not increased compared to unaffected calves.</p> <p>Conclusions</p> <p>The findings are consistent with SR being inherited autosomal recessively. Further studies are however needed to confirm this and therefore a breeding trial is recommended where a suspected heterozygous sire is mated to closely related females.</p

Does a SLAP lesion affect shoulder muscle recruitment as measured by EMG activity during a rugby tackle?

Background: The study objective was to assess the influence of a SLAP lesion on onset of EMG activity in shoulder muscles during a front on rugby football tackle within professional rugby players. Methods: Mixed cross-sectional study evaluating between and within group differences in EMG onset times. Testing was carried out within the physiotherapy department of a university sports medicine clinic. The test group consisted of 7 players with clinically diagnosed SLAP lesions, later verified on arthroscopy. The reference group consisted of 15 uninjured and full time professional rugby players from within the same playing squad. Controlled tackles were performed against a tackle dummy. Onset of EMG activity was assessed from surface EMG of Pectorialis Major, Biceps Brachii, Latissimus Dorsi, Serratus Anterior and Infraspinatus muscles relative to time of impact. Analysis of differences in activation timing between muscles and limbs (injured versus non-injured side and non injured side versus matched reference group). Results: Serratus Anterior was activated prior to all other muscles in all (P = 0.001-0.03) subjects. In the SLAP injured shoulder Biceps was activated later than in the non-injured side. Onset times of all muscles of the noninjured shoulder in the injured player were consistently earlier compared with the reference group. Whereas, within the injured shoulder, all muscle activation timings were later than in the reference group. Conclusions: This study shows that in shoulders with a SLAP lesion there is a trend towards delay in activation time of Biceps and other muscles with the exception of an associated earlier onset of activation of Serratus anterior, possibly due to a coping strategy to protect glenohumeral stability and thoraco-scapular stability. This trend was not statistically significant in all cases

An integrative approach to discovering cryptic species within the Bemisia tabaci whitefly species complex

Bemisia tabaci is a cryptic whitefly-species complex that includes some of the most damaging pests and plant-virus vectors of a diverse range of food and fibre crops worldwide. We combine experimental evidence of: (i) differences in reproductive compatibility, (ii) hybrid verification using a specific nuclear DNA marker and hybrid fertility confirmation and (iii) high-throughput sequencing-derived mitogenomes, to show that the “Mediterranean” (MED) B. tabaci comprises at least two distinct biological species; the globally invasive MED from the Mediterranean Basin and the “African silver-leafing” (ASL) from sub-Saharan Africa, which has no associated invasion records. We demonstrate that, contrary to its common name, the “ASL” does not induce squash silver-leafing symptoms and show that species delimitation based on the widely applied 3.5% partial mtCOI gene sequence divergence threshold produces discordant results, depending on the mtCOI region selected. Of the 292 published mtCOI sequences from MED/ASL groups, 158 (54%) are low quality and/or potential pseudogenes. We demonstrate fundamental deficiencies in delimiting cryptic B. tabaci species, based solely on partial sequences of a mitochondrial barcoding gene. We advocate an integrative approach to reveal the true species richness within cryptic species complexes, which is integral to the deployment of effective pest and disease management strategies

Pumpkin yellow vein mosaic disease is caused by two distinct begomoviruses: complete viral sequences and comparative transmission by an indigenous Bemisia tabaci and the introduced B-biotype

Pumpkin yellow vein mosaic disease (PYVMD) causes significant damage to pumpkin production throughout India. A begomovirus causing PYVMD in South India was characterized recently but the nature of virus causing the disease in North India was not known. Samples of PYVMD were obtained from North India and two putative begomoviruses were PCR-amplified and sequenced. Comparison of complete DNA-A sequences indicated that PYVMD in North and South India were caused by two distinct begomoviruses and shared only approximately 88% DNA-A nucleotide identity. The South Indian isolate was most closely related to Squash leaf curl China virus between 91 and 96% identities, and the two North Indian isolates to Tomato leaf curl New Delhi virus between 94 and 96% identities. The South Indian isolate was previously shown to be transmitted by the indigenous biotype of Bemisia tabaci, however, the situation has since changed with the introduction of the B-biotype to South India in 1999. Comparative transmission experiments between the indigenous biotype v/s the introduced B-biotype for the time required for virus acquisition (30 min v/s 15 min), inoculation (15 min v/s 10 min) and incubation (30 min v/s 4 h) have indicated that the B-biotype transmits the virus quickly and more efficiently than the indigenous biotype. An epidemic of PYVMD was recorded for the first time in South India in 2004 with disease incidences of up to 100% and significant yield losses. This may be due to a combination of several factors including the large numbers of B-biotype populations, the ability of the B-biotype to transmit the virus efficiently and the cultivation of susceptible varieties. These possibilities and the threat to pumpkin cultivation associated with the spread of the B-biotype in India are discussed