Histological differences in the adrenal glands and cortisol levels of suckling dairy goat kids in enriched and non-enriched environments.

Intensive production systems can negatively affect the welfare of goats. Environmental enrichment techniques can be used to reduce stress. The aim of this study was analyze the effect of environmental enrichment on the histological characteristics of adrenal glands, cortisol levels and weekly weight gain of suckling Alpine French male kids under confinement. A randomised design was used to test the effect of the treatment. The animals (n=20) were randomly assigned to two treatments (enriched and non-enriched) with two replicates each. Enrichment elements included elevated sacks of henequen, trunks, tires and coconuts. The cortisol levels were measured weekly. Male kids were euthanized when their weight reached 10kg, and immediately after euthanasia, samples of the adrenal glands were collected. The adrenal glands were weighed and measured, and histological sections were taken and fixed. Four hundred cells were measured from each animal, with two blind measurements taken from each sample. There were no significant differences between experimental groups (P>0.05) in the weigh, size, the area of cells from the glomerulosa and fasciculata areas of the adrenal glands, the cortisol levels and weekly weight gain. However, there were histological differences between the glomerular and fascicular zones of the left and right adrenal glands of the different groups (P<0.05). These findings suggest that adrenal glands of animals in non-enriched environment, contained histological changes, suggestive of increased activity. We suggest testing adrenal histology as an indicator of stress and recommend the use of environmental enrichment as a means to reduce stress.

Effects of imprint training procedure at birth on the reactions of foals at age six months.

REASONS FOR PERFORMING STUDY: While imprint training procedures have been promoted in popular magazines, they have received limited scientific investigation. OBJECTIVES: To determine the effects of a neonatal imprint training procedure on 6-month-old foals and to determine if any one session had a greater effect than others. METHODS: Foals (n = 131) were divided into the following treatments: no imprint training, imprint training at birth, 12, 24 and 48 h after birth or imprint training only at birth, 12, 24, 48, or 72 h after birth. Foals then received minimal human handling until they were tested at 6 months. RESULTS: During training, time to complete exposure to the stimulus was significant for only 2 of 6 stimuli. Percentage change in baseline heart rate was significant for only 2 of 10 stimuli. These 4 effects were randomly spread across treatments. CONCLUSIONS: Neither the number of imprint training sessions (0, 1, or 4) nor the timing of imprint training sessions (none, birth, 12, 24, 48, or 72 h after birth) influenced the foal's behaviour at 6 months of age. POTENTIAL CLINICAL RELEVANCE: In this study, imprint training did not result in better behaved, less reactive foals.