Understanding the trade-off between the environment and fertility in cows and ewes.

The environment contributes to production diseases that in turn badly affect cow performance, fertility and culling. Oestrus intensity is lower in lame cows, and in all cows 26% potential oestrus events are not expressed (to avoid getting pregnant). To understand these trade-offs, we need to know how animals react to their environment and how the environment influences hypothalamus-pituitary-adrenal axis (HPA) interactions with the hypothalamus-pituitary-ovarian axis (HPO). Neurotransmitters control secretion of GnRH into hypophyseal portal blood. GnRH/LH pulse amplitude and frequency drive oestradiol production, culminating in oestrus behaviour and a precisely-timed GnRH/LH surge, all of which are disrupted by poor environments. Responses to peripheral neuronal agents give clues about mechanisms, but do these drugs alter perception of stimuli, or suppress consequent responses? In vitro studies confirm some neuronal interactions between the HPA and HPO; and immuno-histochemistry clarifies the location and sequence of inter-neurone activity within the brain. In both species, exogenous corticoids, ACTH and/or CRH act at the pituitary (reduce LH release by GnRH), and hypothalamus (lower GnRH pulse frequency and delay surge release). This requires inter-neurones as GnRH cells do not have receptors for HPA compounds. There are two (simultaneous, therefore fail-safe?) pathways for CRH suppression of GnRH release via CRH-Receptors: one being the regulation of kisspeptin/dynorphin and other cell types in the hypothalamus, and the other being the direct contact between CRH and GnRH cell terminals in the median eminence. When we domesticate animals, we must provide the best possible environment otherwise animals trade-off with lower production, less intense oestrus behaviour, and impaired fertility. Avoiding life-time peri-parturient problems by managing persistent lactations in cows may be a worthy trade-off on both welfare and economic terms - better than the camouflage use of drugs/hormones/feed additives/intricate technologies? In the long term, getting animals and environment in a more harmonious balance is the ultimate strategy

Gender-selective neural populations: evidence from event-related fMRI repetition suppression

Accurate recognition of gender in another individual is integral to successful human social interaction and to mate selection. When we encounter another person, we are effortlessly able to identify their gender, most often through the information conveyed by their facial features. Faces comprise the most abundantly encountered cue used to classify human gender. Considering the importance of facial information in gender perception, relatively little is known about the mechanisms involved in perceiving gender through human facial cues. We used an event-related fMRI repetition suppression paradigm to explore the neural circuitry underlying gender perception from facial information. Participants viewed brief consecutive images consisting of either gender-same face pairings (two male faces or two female faces) or images of gender-different face pairings (a male face preceded or followed by a female face), while attending to facial attractiveness in both conditions. Using a region-of-interest approach, we found repetition suppression on gender-same trials within the left ventral temporal fusiform gyrus and in the right collateral sulcus. Whole-brain voxel-wise analyses revealed selectivity for face gender again in the right collateral sulcus, in addition to the left cuneus and the right lateral occipital gyrus. Our results indicate that in addition to the face-selective FFA, cortical areas that are not traditionally considered to be “face-selective” are involved in the perception of gender-based facial cues