Abstract: For 20 years after the influenza A virus was discovered in the early 1930s, it was believed to be almost exclusively a human virus. But in the 1950s closely related viruses were discovered in diseases of horses, pigs and birds. Subsequently influenza A viruses were found to occur frequently in many species of birds, particularly ducks, usually without causing disease. Researchers showed that human and animal strains can hybridise thus producing new strains. Such hybrids may be the cause of pandemics in man. Most pandemics have started in China or eastern Russia where many people are in intimate association with animals. This situation provides a breeding ground for new strains of influenza A virus.

Abstract: Sixteen horses were used to determine if number of trials given per training session (5, 10, 15 or 20) affected learning performance in an avoidance conditioning task. The horse had to move from one side of a test pen to the other during an auditory cue presentation to avoid aversive stimulation. A pen 8 mx3.6 m, divided into two equal sections by a 13-cm diameter plastic pipe lying on the ground, was used as the test pen. Painted plywood panels were fastened to the fence in half the pen to help horses distinguish visually between the two parts. A 10-s auditory cue was used as a signal for horses to move from one side of the test pen to the other. A 20-s intertrial interval was used. Training sessions were conducted every third day. Each trial was recorded as an avoidance (the horse completed the task during auditory cue presentation and avoided aversive stimulus) or an error (the horse received aversive stimulus). After completing ten consecutive avoidances (criterion), the horse was removed from the study. Numbers of training sessions, trials, avoidances and errors until reaching criterion were recorded for each horse. Horses varied greatly within these variables with ranges of 3-18 sessions, 37-121 trials, 20-68 avoidances and 17-53 errors to criterion. No differences were detected (P>0.05) in the number of conditioning trials per training session (treatment) for the mean number of trials, avoidances or errors to criterion. Number of training sessions to criterion differed (P<0.01) among treatments, indicating that an optimum number of learning trials per training session might exist. Mean sessions to criterion for horses receiving 5, 10, 15 and 20 trials per session were 15.1+/-1.3, 5.8+/-1.1, 5.3+/-1.1 and 4.6+/-1.1, respectively. Regression analysis indicated that 16.2 trials per training session would minimize number of sessions to criterion. Although it is widely assumed that learning efficiency in horses is decreased when intense activity is concentrated into a small number of sessions, these results indicate that moderate repetition of training activities is needed for efficient learning.

Abstract: Four experiments were designed to find evidence of observational learning in cattle. The experiments were run on ten experimental heifers, each observing a demonstrator mate performing a task, and on ten control heifers, each observing a non-demonstrator mate. The mates and observers were separated by wire netting in Experiments 1-3, but were in the same room in Experiment 4. The task to be learned was to push a panel to get food into a box. All naive animals were able to observe while their mate performed the task. The observers in Experiments 1 and 4 were Salers heifers that had no prior experience of the testing room; those in Experiment 2 were Salers heifers that were accustomed to the room; those in Experiment 3 were Aubrac or Limousin heifers that had already eaten in the room.
The behaviour of the observers was influenced by their mates: activity at or near the boxes was enhanced by the presence of demonstrators in Experiment 2 (box contacts: 38.0 +/- 16.2 vs. 22.1 +/- 11.9 for experimental and control heifers, respectively; P<0.05), while activity in other parts of the room in Experiment 3 was enhanced when non-demonstrator mates were present (wall sniffing: 5.4 +/- 13.9 vs. 13.9 +/- 13.7; P<0.05). Overall, 26 experimental heifers vs. 19 controls learned the task (P>0.05). The time spent eating was longer when the observer only had visual contact with a demonstrator (Experiment 1: 15.9 +/- 1.6 vs. 11.6 +/- 1.8 min), but was lower when physical contacts with the demonstrator were possible (Experiment 4: 4.6 +/- 8.8 vs. 5.4 +/- 2.2 min; P<0.05).
Ten out of the 11 Limousin heifers learned the task, compared with only three out of the nine Aubrac heifers (P<0.05). The latter spent more time near the door and sniffed the walls more often than the former (2.0 +/- 1.9 vs. 0.4 +/- 0.6 min, P<0.05, and 18.1 +/- 13.4 vs. 2.7 +/- 6.5 min, P<0.01), as though they were trying to flee the situation.
When animals observed a demonstrator, their attention was drawn to stimuli involved in the task but acquisition of knowledge was not greatly improved.

Abstract: Studied a herd of 15 Belgian brood-mares and 10 foals. Specific aspects of social structure studied were dominance-subordinance relationships, preferred associates, social spacing, aggression rates, the frequency of aggressions administered down the dominance hierarchy, and interactive play bouts. The rank order of the foals, both before and after weaning, was positively correlated with the rank order of their dams. There was also a significant relationship between a foal's rank and its total aggression or aggression rate per subordinate post-weaning. Higher ranking foals had higher rates of aggression. Over 80% of threats were directed down the dominance hierachy. The play-rank order of the foals, scored by the number of times foal left a play bout, was not significantly correlated with the rank order as scored by agonistic interactions. -from Authors