Prevalence and risk factors of lameness in dairy cattle in Alexandria, Egypt

  Aim of study: Providing further information on the prevalence of lameness in four dairy cattle herds and gain insights into the risk factors associated with the frequency of lameness incidence including farm, frequency of mastitis, and number of lactations.   Area of study: Alexandria, Egypt.   Material and methods: Four dairy Holstein cattle farms near Alexandria Governorate in Egypt were involved in a retrospective investigation of lameness episodes between the years 1987 and 2011. The association between the frequency of lameness injury and the explanatory variables was tested by the maximum likelihood analysis of variance, adopting a loglinear model. The explanatory variables included in the model were farm, frequency of mastitis injury and number of lactations as well as their one-way interactions.   Main results: The prevalence of lameness ranged between zero and 19% in the four farms and the frequency of lameness events (from 0 to 4 times) increased with lactation number and mastitis incidence with correlation coefficients of 0.15 and 0.12, respectively.   Research highlights: Lameness is present in Egyptian dairy cow herds with highly variable prevalence and the risk increases with lactation number and mastitis

Purification and characterization of 9-O-acetylated sialoglycoproteins from leukemic cells and their potential as immunological tool for monitoring childhood acute lymphoblastic leukemia

Sialic acids as terminal residues of oligosaccharide chains play crucial roles in several cellular recognition events. Exploiting the selective affinity of Achatinin-H toward N-acetyl-9-Oacetylneuraminic acid-a2-6-GalNAc, we have demonstrated the presence of 9-O-acetylated sialoglycoproteins (Neu5,9Ac2- GPs) on lymphoblasts of 70 children with acute lymphoblastic leukemia (ALL) and on leukemic cell lines by fluorimetric HPLC and flow cytometric analysis. This study aims to assess the structural aspect of the glycotope of Neu5,9Ac2-GPsALL and to evaluate whether these disease-specific molecules can be used to monitor the clinical outcome of ALL. The Neu5,9Ac2- GPsALL were affinity-purified, and three distinct leukemiaspecific molecular determinants (135, 120, and 90 kDa) were demonstrated bySDS–PAGE, western blotting, and isoelectric focusing. The carbohydrate epitope of Neu5,9Ac2-GPsALL was confirmed by using synthetic sialic acid analogs. The enhanced presence of anti-Neu5,9Ac2-GPALL antibody in ALL patients prompted us to develop an antigen-ELISA using purified Neu5,9Ac2-GPsALL as coating antigens. Purified antigen was able to detect leukemia-specific antibodies at presentation of disease, which gradually decreased with treatment. Longitudinal monitoring of 18 patients revealed that in the early phase of the treatment patients with lower anti-Neu5,9Ac2-GPs showed a better prognosis. Minimal cross-reactivity was observed in other hematological disorders (n¼50) like chronic myeloid leukemia, acute myelogenous leukemia, chronic lymphocytic leukemia, and non-Hodgkin’s lymphoma as well as normal healthy individuals (n¼21). This study demonstrated the potential of purified Neu5,9Ac2-GPsALL as an alternate tool for detection of anti-Neu5,9Ac2-GP antibodies to be helpful for diagnosis and monitoring of childhood ALL patients