Incidence of Ultrathin Descemet Stripping Endothelial Keratoplasty Corneal Graft Rejection following Steroid Discontinuation.

Purpose/Aims: To determine the incidence of corneal graft rejection in patients with approximately 1 year of steroid therapy following uDSEK. A shortened course of corticosteroids may be beneficial and a viable option in Ultrathin Descemet's Stripping Endothelial Keratoplasty (uDSEK).Materials and Methods: This retrospective cohort study evaluated corneal graft rejection rate in 170 cases of uDSEK that met inclusion criteria with approximately 1 year of steroid therapy. Corneal graft rejection was defined by anterior chamber cell/flare, keratic precipitates with/without corneal edema, and/or a rejection line. The following were collected retrospectively from January 1, 2005 through January 1, 2013: gender, age, race, indication for uDSEK, length of follow-up, length of steroid therapy. Continuous data were compared using Wilcoxon Rank Sum Test and categorical data were compared using Fisher's Exact Test.Results: The included eyes had an average length of steroid therapy of 431 days (range 85-720 days) with an average follow-up of 1274 days (range 395-3186 days). During the follow-up period without steroid, 5 of the 170 eyes were diagnosed with rejection (2.94%). Of the five eyes that experienced rejection, four eyes resolved after topical prednisone was reinstituted alone and did not require repeat uDSEK. The other eye was lost to follow-up. The cumulative probability of rejection after steroid cessation was calculated at 0.67% after 12 months, 2.20% after 18 months, 3.08% after 24 months, and 4.55% after 36 months.Conclusion: Discontinuation of topical steroid at approximately 1 year after uDSEK results in a low rate of corneal graft rejection and may prove extended use unnecessary.

Customized recommendations for production management clusters of North American automatic milking systems.

Automatic milking systems (AMS) are implemented in a variety of situations and environments. Consequently, there is a need to characterize individual farming practices and regional challenges to streamline management advice and objectives for producers. Benchmarking is often used in the dairy industry to compare farms by computing percentile ranks of the production values of groups of farms. Grouping for conventional benchmarking is commonly limited to the use of a few factors such as farms' geographic region or breed of cattle. We hypothesized that herds' production data and management information could be clustered in a meaningful way using cluster analysis and that this clustering approach would yield better peer groups of farms than benchmarking methods based on criteria such as country, region, breed, or breed and region. By applying mixed latent-class model-based cluster analysis to 529 North American AMS dairy farms with respect to 18 significant risk factors, 6 clusters were identified. Each cluster (i.e., peer group) represented unique management styles, challenges, and production patterns. When compared with peer groups based on criteria similar to the conventional benchmarking standards, the 6 clusters better predicted milk produced (kilograms) per robot per day. Each cluster represented a unique management and production pattern that requires specialized advice. For example, cluster 1 farms were those that recently installed AMS robots, whereas cluster 3 farms (the most northern farms) fed high amounts of concentrates through the robot to compensate for low-energy feed in the bunk. In addition to general recommendations for farms within a cluster, individual farms can generate their own specific goals by comparing themselves to farms within their cluster. This is very comparable to benchmarking but adds the specific characteristics of the peer group, resulting in better farm management advice. The improvement that cluster analysis allows for is characterized by the multivariable approach and the fact that comparisons between production units can be accomplished within a cluster and between clusters as a choice.

Factors associated with increased milk production for automatic milking systems.

Automatic milking systems (AMS) are increasingly popular throughout the world. Our objective was to analyze 635 North American dairy farms with AMS for (risk) factors associated with increased milk production per cow per day and milk production per robot per day. We used multivariable generalized mixed linear regressions, which identified several significant risk factors and interactions of risk factors associated with milk production. Free traffic was associated with increased production per cow and per robot per day compared with forced systems, and the presence of a single robot per pen was associated with decreased production per robot per day compared with pens using 2 robots. Retrofitted farms had significantly less production in the first 4 yr since installation compared with production after 4 yr of installation. In contrast, newly built farms did not see a significant change in production over time since installation. Overall, retrofitted farms did not produce significantly more or less milk than newly constructed farms. Detailed knowledge of factors associated with increased production of AMS will help guide future recommendations to producers looking to transition to an AMS and maximize their production.