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The aim of this work was to critically assess if functional near infrared spectroscopy (fNIRS) can be profitably used as a tool for noninvasive recording of brain functions and emotions in sheep. We considered an experimental design including advances in instrumentation (customized wireless multi-distance fNIRS system), more accurate physical modelling (two-layer model for photon diffusion and 3D Monte Carlo simulations), support from neuroanatomical tools (positioning of the fNIRS probe by MRI and DTI data of the very same animals), and rigorous protocols (motor task, startling test) for testing the behavioral response of freely moving sheep. Almost no hemodynamic response was found in the extra-cerebral region in both the motor task and the startling test. In the motor task, as expected we found a canonical hemodynamic response in the cerebral region when sheep were walking. In the startling test, the measured hemodynamic response in the cerebral region was mainly from movement. Overall, these results indicate that with the current setup and probe positioning we are primarily measuring the motor area of the sheep brain, and not probing the too deeply located cortical areas related to processing of emotions.

In this study, we characterized the morphological aspects of the early development of the head of the alpaca (Vicugna pacos) and identified the main structures of the central nervous system during the first trimester of pregnancy. The topography and the cytoarchitecture of the fetal brain regions were described by histological analysis of the brain sections. We performed this analysis on alpaca embryos and fetuses presumably aged 20, 30, 45, and 90 days. For the description of the external body structures we considered the shape of the head, the development of the optic primordium, the dorsal curvature of the body, the limb buds, the umbilical cord and relative vessels, and the thickness and transparency of the skin. The prosencephalic, mesencephalic, and the rhomboencephalic vesicles were described by analyzing sagittal sections of the head. The present article provides the first progressive morphological and anatomical description of alpaca brain during early development. A detailed study represents an important basis to further understand the phases of prenatal development in this species, since information about alpaca embryology in incomplete and reproductive failure is a relevant factor. These data are important also for interspecies comparisons and application of reproductive biotechnologies. Anat Rec, 302:1226-1237, 2019. © 2018 Wiley Periodicals, Inc., (© 2018 Wiley Periodicals, Inc.)

The retia mirabilia are vascular nets composed of small vessels dispersed among numerous veins, allowing blood storage, regulation of flow and pressure damping effects. Here, we investigated their potential role during the diving phase of the bottlenose dolphin ( Tursiops truncatus ). To this effect, the whole vertebral retia mirabilia of a series of dolphins were removed during post-mortem analysis and examined to assess vessel diameters, and estimate vascular volume and flow rate. We formulated a new hemodynamic model to help clarify vascular dynamics throughout the diving phase, based on the total blood volume of a bottlenose dolphin, and using data available about the perfusion of the main organs and body systems. We computed the minimum blood perfusion necessary to the internal organs, and the stroke volume and cardiac output during the surface state. We then simulated breath-holding conditions and perfusion of the internal organs under the diving-induced bradycardia and reduction of stroke volume and cardiac output, using 10 beats min -1 as the limit for the heart rate for an extended dive of over 3 min. Within these simulated conditions, the retia mirabilia play a vital role as reservoirs of oxygenated blood that permit functional performances and survival of the heart and brain. Our theoretical model, based on the actual blood capacity of the retia mirabilia and available data on organ perfusion, considers the dynamic trend of vasoconstriction during the diving phase and may represent a baseline for future studies on the diving physiology of dolphins and especially for the blood supply to their brain., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2019. Published by The Company of Biologists Ltd.)

The anatomy of the giraffe (Giraffa camelopardalis Linnaeus, 1758) has been poorly studied, except for the circulatory system. In particular, only a handful of studies have concerned the brain of this species since the first description in 1839. Accordingly, only a very few articles discussing encephalization mentioned the giraffe or used it in their calculations. In this article, we performed a thorough examination of the literature including old and grey, regarding the central nervous system of the giraffe. Furthermore, we examined the brain of 3 giraffes, and calculated the encephalization quotient (EQ) of the species, based on our own data and the values found in the literature. We also revised the pre-existing literature and re-mapped the main sulci based on current comparative interpretation and anatomical nomenclature. Our results were compared to those of other selected significant mammals. The mean brain weight was of 719.9 ± 12.5 g. Our data indicate that the EQ of the giraffe is 0.64 and matches that of the typical ungulate, despite having the largest brain among terrestrial Cetartiodactyla. This emphasizes that the giraffe is a highly specialized mammal, within the limitations of its clad. Anat Rec, 300:1502-1511, 2017. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)

In the present study we examined the brain of fetal, newborn, and adult pigs raised for meat production. The fresh and formalin-fixed weights of the brain have been recorded and used, together with body weight, to calculate the Encephalization Quotient (EQ). The weight of the cerebellum has been used to calculate the Cerebellar Quotient (CQ). The results have been discussed together with analogue data obtained in other terrestrial Cetartiodactyla (including the domestic bovine, sheep, goat, and camel), domesticated Carnivora, Proboscidata, and Primates. Our study, based on a relatively large experimental series, corrects former observations present in the literature based on smaller samples, and emphasizes that the domestic pig has a small brain relative to its body size (EQ = 0.38 for adults), possibly due to factors linked to the necessity of meat production and improved body weight. Comparison with other terrestrial Cetartiodactyla indicates a similar trend for all domesticated species.

The domestic bovine Bos taurus is raised worldwide for meat and milk production, or even for field work. However the functional anatomy of its central nervous system has received limited attention and most of the reported data in textbooks and reviews are derived from single specimens or relatively old literature. Here we report information on the brain of Bos taurus obtained by sampling 158 individuals, 150 of which at local abattoirs and 8 in the dissecting room, these latter subsequently formalin-fixed. Using body weight and fresh brain weight we calculated the Encephalization Quotient (EQ), and Cerebellar Quotient (CQ). Formalin-fixed brains sampled in the necropsy room were used to calculate the absolute and relative weight of the major components of the brain. The data that we obtained indicate that the domestic bovine Bos taurus possesses a large, convoluted brain, with a slightly lower weight than expected for an animal of its mass. Comparisons with other terrestrial and marine members of the order Cetartiodactyla suggested close similarity with other species with the same feeding adaptations, and with representative baleen whales. On the other hand differences with fish-hunting toothed whales suggest separate evolutionary pathways in brain evolution. Comparison with the other large domestic herbivore Equus caballus (belonging to the order Perissodactyla) indicates that Bos taurus underwent heavier selection of bodily traits, which is also possibly reflected in a comparatively lower EQ than in the horse. The data analyzed suggest that the brain of domestic bovine is potentially interesting for comparative neuroscience studies and may represents an alternative model to investigate neurodegeneration processes.

The horse is a common domestic animal whose anatomy has been studied since the XVI century. However, a modern neuroanatomy of this species does not exist and most of the data utilized in textbooks and reviews derive from single specimens or relatively old literature. Here, we report information on the brain of Equus caballus obtained by sampling 131 horses, including brain weight (as a whole and subdivided into its constituents), encephalization quotient (EQ), and cerebellar quotient (CQ), and comparisons with what is known about other relevant species. The mean weight of the fresh brains in our experimental series was 598.63 g (SEM ± 7.65), with a mean body weight of 514.12 kg (SEM ± 15.42). The EQ was 0.78 and the CQ was 0.841. The data we obtained indicate that the horse possesses a large, convoluted brain, with a weight similar to that of other hoofed species of like mass. However, the shape of the brain, the noteworthy folding of the neocortex, and the peculiar longitudinal distribution of the gyri suggest an evolutionary specificity at least partially separate from that of the Cetartiodactyla (even-toed mammals and cetaceans) with whom Perissodactyla (odd-toed mammals) are often grouped.

Metallothioneins (MT) are a family of proteins actively involved in metal detoxification and storage as well as in prevention of free-radical damage. Changes in the levels of MT have been described in a number of neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, prion protein disease, Binswanger type of subcortical vascular dementia, and amyotrophic lateral sclerosis. This suggests that MT functions might be more complex and vast than what was initially thought. In this review, we summarize the current knowledge on the potential involvement of MT in the mentioned neurodegenerative diseases while also discussing the emerging evidence proposing MT modulation as a feasible therapeutic approach. Enhancing repair mechanisms after neurological damage and/or protection against oxidative stress through a proper modulation of this family of protein might indeed represent an important avenue to cope neurodegeneration.

Estrogens diversely affect various physiological processes by genomic or non-genomic mechanisms, in both excitable and non-excitable cells. Additional to the trophic effects of estrogens promoting cell growth and differentiation, recent experimental evidence highlights their involvement in the regulation of intracellular Ca(2+) homeostasis. The effects of estrogens on excitable cells are well documented. However, these steroids also influence numerous physiological events in non-excitable cells, such as fibroblasts or vascular endothelial cells. We have focused our attention on an immortalized endothelial-like cell line derived from fetal bovine cerebellum. Estradiol (E(2)) effects on intracellular Ca(2+) homeostasis were tested by varying the exposure time to the hormone (8, 24, 48 h). Calcium measurements were performed with genetically encoded Ca(2+) probes (Cameleons) targeted to the main subcellular compartments involved in intracellular Ca(2+) homeostasis (cytosol, endoplasmic reticulum, mitochondria). Mitochondrial Ca(2+) uptake significantly decreased after 48-h exposure to E(2), whereas cytosolic and endoplasmic reticulum responses were unaffected. The effect of E(2) on mitochondrial Ca(2+) handling was blocked by ICI 182,780, a pure estrogen receptor antagonist, suggesting that the effect was estrogen-receptor-mediated. To evaluate whether the decrease of Ca(2+) uptake affected mitochondrial membrane potential (ΔΨm), cells were monitored in the presence of tetra-methyl-rhodamine-methylester; no significant changes were seen between cells treated with E(2) and controls. To investigate a mechanism of action, we assessed the possibile involvement of the permeability transition pore (PTP), an inner mitochondrial membrane channel influencing energy metabolism and cell viability. We treated cells with CyclosporinA (CsA), which binds to the matrix chaperone cyclophilin-D and regulates PTP opening. CsA reversed the effects of a 48-h treatment with E(2), suggesting a possible transcriptional modulation of proteins involved in the mitochondrial permeability transition process.

The claustrum has been described in the forebrain of all mammals studied so far. It has been suggested that the claustrum plays a role in the integration of multisensory information: however, its detailed structure and function remain enigmatic. The human claustrum is a thin, irregular, sheet of grey matter located between the inner surface of the insular cortex and the outer surface of the putamen. Recently, the G-protein gamma2 subunit (Gng2) was proposed as a specific claustrum marker in the rat, and used to better delineate its anatomical boundaries and connections. Additional claustral markers proposed in mammals include Netrin-G2 in the monkey and latexin in the cat. Here we report the expression and distribution of Gng2 and Netrin-G2 in human post-mortem samples of the claustrum and adjacent structures. Gng2 immunoreactivity was detected in the neuropil of the claustrum and of the insular cortex but not in the putamen. A faint labelling was present also in the external and extreme capsules. Double-labelling experiments indicate that Gng2 is also expressed in glial cells. Netrin-G2 labelling was seen in neuronal cell bodies throughout the claustrum and the insular cortex but not in the medially adjacent putamen. No latexin immunoreactive element was detected in the claustrum or adjacent structures. Our results confirm that both the Gng2 and the Netrin-G2 proteins show an affinity to the claustrum and related formations also in the human brain. The presence of Gng2 and Netrin-G2 immunoreactive elements in the insular cortex, but not in the putamen, suggests a possible common ontogeny of the claustrum and insula.

Copper dyshomeostasis has been suggested as an aetiological risk factor for some neurodegenerative diseases, such as Alzheimer's disease. However, the precise mechanism at the base of this involvement is still obscure. In this work, we show the effects of a copper-deficient diet in aged CD1 mice and the influence of such a diet on: a) the concentration of various metal ions (aluminium, copper, iron, calcium, zinc) in the main organs and in different brain areas; b) the alteration of metallothioneins I-II and tyrosine hydroxylase immunopositivity in the brain; c) behavioural tests (open field, pole, predatory aggression, and habituation/dishabituation smell tests). Our data suggested that the copper-deficiency was able to produce a sort of "domino effect" which altered the concentration of the other tested metal ions in the main organs as well as in the brain, without, however, significantly affecting the animal behaviour.

Accumulation of metal ions in the brain contributes to heighten oxidative stress and neuronal damage as evidenced in aging and neurodegenerative diseases, both in humans and in animals. In the present paper we report the analysis of Cu, Zn and Mn in the brain of two series of respectively young (8-16 months) and adult (9-12 years) bovines. Our data indicate that the concentrations of Cu varied of one order of magnitude between 1.67 and 15.7microg/g wet tissue; the levels of Zn varied between 6.13 and 17.07microg/g wet tissue and the values of Mn resulted between 0.19 and 1.24microg/g wet tissue. We found relevant age-dependent differences in the distribution of Cu and Zn, whose concentrations were markedly higher in older animals. By contrast, Mn seemed to redistribute in the different cerebral areas rather than drastically change with age. Tissues from bovine brain were also analysed immunohistochemically for the presence and distribution of metallothionein I/II and also for the expression of glial fibrillary acidic protein. Metallothionein I/II immunoreactive elements included ependymal cells lining the lateral ventricles and neural cells in middle layer of the cerebellar cortex. No age differences were evident between calves and adult. The presence of liquor-contacting metallothionein I/II in cells confirms that their functions in the central nervous system are not yet completely established.

This study describes a method of obtaining primary cultures from the cerebral cortex and the hypothalamus of bovine fetuses. We describe here the influence of tissue origin, developmental stage and culture medium conditions on cell differentiation and prevalence of neurons vs glial cells. To identify optimal conditions for obtaining and growing viable neurons and astrocytes in culture, we tested early, middle and late stages of development. Explants from cortex, early stages (week 10 of pregnancy out of 36) and low fetal calf serum concentration (1%) yielded maximum amounts of neurons. Fresh and thawed tissues gave comparable results.

Several data suggest that melatonin may influence avian reproduction by acting at the level of the hypothalamic-hypophisial-gonadal axis, and/or on neural circuits controlling reproductive behaviours. The action of melatonin is exerted through specific receptors whose distribution and pharmacological properties have been extensively investigated. This review will focus on the distribution, sexual dimorphism, and dependence upon the photoperiod of melatonin binding sites in avian species with a special emphasis on Japanese quail. Melatonin receptors are widely distributed in avian brain. They are mostly present in the visual pathways of all the investigated species and in the song controlling nuclei of oscine birds. Sexual dimorphism of melatonin binding sites (higher density in males than in females) was detected in some telencephalic nuclei of songbirds, in the visual pathways, and in the preoptic area of quail. The last region plays a key role in the activation of male quail copulatory behaviour and it hosts a large population of gonadotropin-releasing hormone-containing neurons. Sexual dimorphism of melatonin-binding sites in the above-mentioned regions suggests a differential role for this hormone in the modulation of visual perception, gonadotropin production, and seasonally activated behaviours in male and female quail. Further studies are necessary to understand interrelationships among photic cues, gonadal steroids, density, and sexually dimorphic distribution of melatonin receptors., (Copyright 2001 Wiley-Liss, Inc.)

The two species of elephants (Indian: Elephas maximus and African: Loxodonta africana) possess the largest brain among land mammals. Due to its size, the elephant brain is discussed in virtually every paper dealing with the evolution of the central nervous system of mammals and comparative brain size. Studies on the social habits of elephants also deal with the skills and the "intelligence" and brain size of these species. Yet most of the descriptions and conclusions reported in comparative studies rely on second-hand data derived from investigations performed several decades before, often dating as far back as the XIX century. Furthermore, many of the original papers actually describing gross and detailed features of the brain of elephants are either no longer available, are written in languages other than English, or are difficult to trace. The present study gives a short description of the anatomy of the central nervous system of elephants, with special attention to its distinctive features, reports all available literature on the subject, and briefly discusses its origins and rationale.

In the present investigation we studied the presence and distribution of histochemically detected neuronal NADPH-diaphorase (ND) in the brain of the budgerigar, Melopsittacus undulatus. Positive neurons are widely distributed throughout the central nervous system. ND-containing neurons are present in the telencephalon and the paleostriatal-parolfactory lobe complex. Positive cells were observed also in the neostriatum, including the main auditory area (field L), in several nuclei of the archistriatum and in the hyperstriatum (accessory, dorsal, and ventral). In the diencephalon, positive neurons were present both in the lateral hypothalamic and periventricular areas, and in a segregate area at the confluence of the anterior commissure and the lateral prosencephalic bundle. A group of positive perikarya was located lateral to the dorsal part of the IIIrd ventricle, and continued laterally into the thalamus. Weakly stained neurons were observed in the thalamic dorsomedial posterior nucleus. In the mesencephalon, ND-containing neurons were scattered in the reticular formation (pars lateralis and pars medialis) and in the optic tecta. A large population of positive neurons was observed in the substantia nigra, the ventral area of Tsai and the nucleus interpeduncularis. Positive neurons extended through the tegmental nuclei to the locus coeruleus. In the cerebellum, the granular neurons were weakly stained and the internal cerebellar nuclei were surrounded by a wide network of positive fibers. In the medulla the number of positive cells was highly reduced, but stained neurons were observed in the cochlear as well in the vestibular nuclei. The data here presented suggest that the distribution of ND-containing neurons in the brain of the budgerigar is different from those of the chicken and quail. The locations of positive neurons suggest also a possible involvement in sound perception and production pathways, and visual perception.

2-[125I]iodomelatonin was used to study the distribution and properties of the melatonin receptor in the Japanese quail brain. High receptor density was detected in the major targets of direct retinal input (optic tectum, nucleus of the optic basal rout, ventrolateral geniculate nucleus), as well as areas representing terminals in the visual pathways (nucleus rotundus, ectostriatum, thalamo-hyperstriatal pathway). Binding was also found in the piriform cortex, the hypophyseal pars tuberalis, the oculomotorius nucleus and the associated Edinger-Westphal nucleus, and in the nuclei of the third, fourth and sixth cranial nerves. A comparison of the receptor pharmacological profile to that of the mammalian brain demonstrated pharmacological identity of the two binding sites. In the saturation experiments, GPT gamma S decreased the binding affinity, numerical Kd values increasing from approximately 35 pM to approximately 150 pM.

The distribution of putative melatonin receptors in the brains of two Old World primates of the superfamily Catarrhina, Cercopithecus aethiops and Papio ursinus, was characterized using 2-[125I]iodomelatonin autoradiography. The specific binding demonstrated a discrete distribution pattern. The median eminence was intensely labelled, and examination at the light microscopic level demonstrated that the binding was confined to the small layer of cells comprising the pars tuberalis of the pituitary gland. The collar of pars distalis, present in the baboon (Papio ursinus), was diffusely labelled. No binding was detected in the pars distalis proper or the neural lobe of the pituitary gland. The binding in the suprachiasmatic nuclei was weaker, but well discernible. Diffuse faint specific binding was found in the frontal cortex and the dentate gyrus of the hippocampus. Two non-neural sites expressed strong, well-delineated binding: the walls of some brain blood vessels (the vertebral and spinal arteries, the inferior cerebellar and acoustic arteries, the basilar, pericallosal, internal carotid arteries, the arteries forming the circle of Willis) and the choroid plexuses. Binding in the arteries of the circle of Willis, the pars tuberalis and the suprachiasmatic nuclei was readily displaceable. Addition of 1 microM unlabelled 2-iodomelatonin following 45 min of preincubation with the radioactive ligand completely abrogated the binding. Co-incubation with guanosine 5'-O-(3-thiotriphosphate) led to a significant decrease in the apparent binding density in the pars tuberalis and abolished binding in the suprachiasmatic nuclei, but was without effect on the binding in the walls of the adjacent arteries, forming the circle of Willis, in the cortex and in the hippocampus. This qualitative distribution pattern demonstrates that in the two primate species studied, melatonin high-affinity, G-protein-linked binding sites are present in the pars tuberalis and the hypothalamic suprachiasmatic nuclei, and that melatonin may be acting as a synchronizer of the endogenous pacemakers' circadian activity, apart from its possible reproductive effects at the level of pars tuberalis, where the highest receptor density was observed. The strongly labelled arterial walls, and the flimsy labelled cortex and hippocampus, expressed different characteristics: though the binding was readily reversible, it was apparently not regulated by a guanine nucleotide-binding protein.

Melatonin receptors were characterized in the brains of three mammals (rabbit, horse and sheep) by an in vitro binding technique, using 2-[125I]iodomelatonin as labelled ligand. Although binding sites for melatonin have been described recently in several vertebrate species (including the sheep), the rabbit and the horse have not been the subject of investigation so far. Apart from characterization, the present report describes receptor distribution in a number of brain regions, thus allowing for direct interspecies comparison under the same methodological conditions. 2-[125I]iodomelatonin labelled high-affinity binding sites in crude membrane preparations from these species. A series of kinetic and saturation experiments revealed that the binding was rapid, stable, saturable, reversible, of high affinity (Kd in the low picomolar range) and low capacity (Bmax between 1 and 20 fmol/mg protein). The competition studies showed that the relative order of potency of a variety of indoles for inhibition of 2-[125I]iodomelatonin binding was as follows: 2-iodomelatonin greater than 6-chloromelatonin greater than melatonin much much greater than 5-methoxytryptophol greater than 5-methoxytryptamine, and that it was similar in the different brain regions. Prazosin, which has been reported as an extremely potent melatonin analog in the hamster brain, possessed no potency in all preparations from different regions in the three species under investigation. The regional distribution of the receptor showed insignificant species differences. Highest density was always recorded in the median eminence/pars tuberalis (ME/PT) area. Other regions (SCN, POA and certain cortical areas), showed lower, but significant, receptor content. Saturation and competition studies revealed that these binding sites were also of high affinity, low capacity and high specificity.(ABSTRACT TRUNCATED AT 250 WORDS)

The dimorphism among male, female and freemartin intersex bovines, focusing on the vermal lobules VIII and IX, was analyzed using a novel data analytics approach to quantify morphometric differences in the cytoarchitecture of digitalized sections of the cerebellum. This methodology consists of multivariate and multi-aspect testing for cytoarchitecture-ranking, based on neuronal cell complexity among populations defined by factors, such as sex, age or pathology. In this context, we computed a set of shape descriptors of the neural cell morphology, categorized them into three domains named size, regularity and density, respectively. The output and results of our methodology are multivariate in nature, allowing an in-depth analysis of the cytoarchitectonic organization and morphology of cells. Interestingly, the Purkinje neurons and the underlying granule cells revealed the same morphological pattern: female possessed larger, denser and more irregular neurons than males. In the Freemartin, Purkinje neurons showed an intermediate setting between males and females, while the granule cells were the largest, most regular and dense. This methodology could be a powerful instrument to carry out morphometric analysis providing robust bases for objective tissue screening, especially in the field of neurodegenerative pathologies. [ABSTRACT FROM AUTHOR]