diff --git a/app/models/ticket.rb b/app/models/ticket.rb
index 742917411..e24695ff7 100644
--- a/app/models/ticket.rb
+++ b/app/models/ticket.rb
@@ -4,8 +4,11 @@ class Ticket < ApplicationModel
   include Ticket::Escalation
   include Ticket::Subject
   include Ticket::Permission
+  require 'ticket/assets'
   include Ticket::Assets
+  require 'ticket/history_log'
   include Ticket::HistoryLog
+  require 'ticket/activity_stream_log'
   include Ticket::ActivityStreamLog
   extend Ticket::Search
 
diff --git a/app/models/ticket/article.rb b/app/models/ticket/article.rb
index 698b00c49..61810d884 100644
--- a/app/models/ticket/article.rb
+++ b/app/models/ticket/article.rb
@@ -1,8 +1,11 @@
 # Copyright (C) 2012-2013 Zammad Foundation, http://zammad-foundation.org/
 
 class Ticket::Article < ApplicationModel
+  require 'ticket/article/assets'
   include Ticket::Article::Assets
+  require 'ticket/article/history_log'
   include Ticket::Article::HistoryLog
+  require 'ticket/article/activity_stream_log'
   include Ticket::Article::ActivityStreamLog
 
   belongs_to    :ticket