Impact of facial conformation on canine health: Brachycephalic Obstructive Airway Syndrome

The domestic dog may be the most morphologically diverse terrestrial mammalian species known to man; pedigree dogs are artificially selected for extreme aesthetics dictated by formal Breed Standards, and breed-related disorders linked to conformation are ubiquitous and diverse. Brachycephaly–foreshortening of the facial skeleton–is a discrete mutation that has been selected for in many popular dog breeds e.g. the Bulldog, Pug, and French Bulldog. A chronic, debilitating respiratory syndrome, whereby soft tissue blocks the airways, predominantly affects dogs with this conformation, and thus is labelled Brachycephalic Obstructive Airway Syndrome (BOAS). Despite the name of the syndrome, scientific evidence quantitatively linking brachycephaly with BOAS is lacking, but it could aid efforts to select for healthier conformations. Here we show, in (1) an exploratory study of 700 dogs of diverse breeds and conformations, and (2) a confirmatory study of 154 brachycephalic dogs, that BOAS risk increases sharply in a non-linear manner as relative muzzle length shortens. BOAS only occurred in dogs whose muzzles comprised less than half their cranial lengths. Thicker neck girths also increased BOAS risk in both populations: a risk factor for human sleep apnoea and not previously realised in dogs; and obesity was found to further increase BOAS risk. This study provides evidence that breeding for brachycephaly leads to an increased risk of BOAS in dogs, with risk increasing as the morphology becomes more exaggerated. As such, dog breeders and buyers should be aware of this risk when selecting dogs, and breeding organisations should actively discourage exaggeration of this high-risk conformation in breed standards and the show ring

A comparative analysis of sustainable construction tools and their applicability to the housing sector in two countries; Burkina Faso and Sri Lanka.

Abstract The buildings and construction sector is responsible for nearly 40% of the total greenhouse emissions (GHG). Considering 50% of the building stock that will exist in 2050 is yet to be built and most of it will be devoted to housing; the sector is a determinant and transformative force to strengthen sustainability, reducing CO2 emissions and environmental degradation worldwide. Most of the increase in construction and housing is set to occur in developing countries and mainly in cities in Asia and Africa. This global picture places new housing programs in the rapidly urbanising regions as potential agents of sustainable transformation, with positive outcomes for both communities and the environment. Investing in sustainable housing has significant and real value in reducing emissions, confronting climate change, and generating better planned, inclusive, and sustainable cities. The holistic benefit achieved with the implementation of carbon neutral and carbon negative technologies is often scattered, and an integrated view of it would be a key tool to support the development of sustainable housing programmes. Considering that technologies to decarbonize and render the construction sector more sustainable have already been developed, there is a need to contrast their applicability to different countries and contexts in order to verify their functionality and identify gaps for improvement. The recent decade has witnessed a significant improvement at the global level with regards to the application of the concept of sustainability to the built environment, this being demonstrated by the multiple sustainability ratings and frameworks being developed to certify building performance. Their adoption has been critically important in most regions in the so-called Global North, where countries have started enforcing them at a normative level. While these tools’ accuracy and comprehensiveness could be disputed, their importance in promoting a systematic standardisation of the adoption of sustainability measures in the built environment is endorsed. Nevertheless, the diffusion of such tools and frameworks across rapidly urbanising middle and low-income countries has been so far extremely limited. There are myriad reasons why this is the case: tools based for high-income country contexts, their complexity, the need for accurate data and specific capacity for their adoption and diffusion, the lack of contextual relevance with regards to the specific market, culture and behavioural dynamics, and more. The following paper aims at demonstrating the value of shifting toward sustainable building practices by a comparative analysis of existing global tools and certifications and their applicability to low and middle-income countries undergoing a rapid urbanisation process. It proposes a three-phased multi-stakeholders methodology. The outcome of these three phases is combined, providing a more appropriate definition of effective and operative guidelines and tools for sustainable housing in rapidly urbanising middle and lowincome regions.</jats:p

Revisão anatômica do seio venoso sagital dorsal no crânio de cães braquicéfalos Anatomic features of the dorsal venous sinus in skull of brachycephalous dogs

Os seios venosos do crânio realizam a drenagem do cérebro e da medula espinhal, a fim de manter a homeostasia e o perfeito funcionamento do sistema nervoso central. Lesões na rede venosa cerebral podem causar déficits severos tais como hemiplegia, hemorragia, coma e morte. Os seios venosos são importantes pontos de referência para a realização de técnicas cirúrgicas de acesso ao cérebro. Este estudo visou analisar o trajeto do seio venoso sagital dorsal no crânio de cães braquicéfalos. Os animais braquicéfalos possuem crânios curtos e com características biométricas específicas. Foram utilizados 8 crânios de cães da raça Boxer, que foram submetidos à injeção de látex com pigmento corado e sulfato de bário. Após a perfusão, foram feitas radiografias contrastadas e imagens de tomografia computadorizada para relacionar o seio venoso com a estrutura óssea e dimensões relativas da calota craniana. Os crânios apresentaram índice cefálico (IC) médio de 91,24&plusmn;8,34mm e índice crânio-facial (ICF) médio de 2,89&plusmn;0,23mm. As mensurações do seio venoso sagital dorsal, relativas à calota craniana, apresentaram os seguintes valores médios: Área = 10,18&plusmn;4,69mm²; D1 = 11,84&plusmn;2,35mm; D2 = 19,57&plusmn;2,61mm; D3 = 17,88&plusmn;2,31mm; D4 = 25,32&plusmn;5,68mm; e D5= 24,84&plusmn;4,40mm.<br>The dorsal venous sinuses of the Dura mater perform the cerebral and spinal cord drainage to keep homeostasis of the Central Nervous System. Injuries in the cerebral venous network may cause severe deficits, including hemiplegia, hemorrhage, coma and death. The main landmark for neurologic surgery is the Dura mater venous sinus. The aim of this study is to analyse the pathway of the Sinus sagittalis dorsalis in the brachycephalous skull, as the brachycephalous dogs have specific characteristics. The skulls were taken from 8 Boxer dogs and venous perfusion with latex and barium sulfate solution was performed. After the perfusion, radiographies and tomographies were obtained to relate the dorsal sagittal sinus and the skull averages. The cephalic index showed mean values of 91.24&plusmn;8.34cm, and the cranio-facial index was 2.89&plusmn;0.23cm. The venous sinus mensuration interface to the skull was: Área = 10.18&plusmn;4.69mm²; D1 = 11.84&plusmn;2.35mm; D2 = 19.57&plusmn;2.61mm; D3 = 17.88&plusmn;2.31mm; D4 = 25.32&plusmn;5.68mm e D5 = 24.84&plusmn;4.40mm

Human Induced Rotation and Reorganization of the Brain of Domestic Dogs

Domestic dogs exhibit an extraordinary degree of morphological diversity. Such breed-to-breed variability applies equally to the canine skull, however little is known about whether this translates to systematic differences in cerebral organization. By looking at the paramedian sagittal magnetic resonance image slice of canine brains across a range of animals with different skull shapes (N = 13), we found that the relative reduction in skull length compared to width (measured by Cephalic Index) was significantly correlated to a progressive ventral pitching of the primary longitudinal brain axis (r = 0.83), as well as with a ventral shift in the position of the olfactory lobe (r = 0.81). Furthermore, these findings were independent of estimated brain size or body weight. Since brachycephaly has arisen from generations of highly selective breeding, this study suggests that the remarkable diversity in domesticated dogs' body shape and size appears to also have led to human-induced adaptations in the organization of the canine brain

Morphometric and immunohistochemical study of the omasum of red deer during prenatal development

The red deer is an important study species because of its value in the national economy and because it provides a wealth of genetic material. To date, there has been little research into the prenatal development of the stomach of ruminants, and none of the red deer. We therefore performed a histological evaluation of the ontogenesis of the omasum in the red deer. Histomorphometric and immunohistochemical analyses were carried out on 50 embryos and fetuses of deer from the initial stages of prenatal life until birth. For test purposes, the animals were divided into five experimental groups: Group I (1.4–3.6 cm crown–rump length, CRL; 30–60 days, 1–25% of gestation); Group II (4.5–7.2 cm CRL; 67–90 days, 25–35% of gestation); Group III (8–19 cm CRL; 97–135 days, 35–50% of gestation); Group IV (21–33 cm CRL; 142–191 days, 50–70% of gestation); and Group V (36–40 cm CRL; 205–235 days, 75–100% of gestation). At 67 embryonic days, the omasum wall was differentiated, and comprised three layers: the epithelial layer, pluripotential blastemic tissue and serosa. The stratification of the epithelial layer was accompanied by changes in its structure, with the appearance of four laminae of different sizes; in order of appearance these were: primary at 67 days, secondary at 90 days, tertiary at 97 days and quaternary at 135 days. At around mid-gestation, lateral evaginations were formed from the stratum basale of the primary and secondary smaller laminae. These were the primitive corneum papillae. From 205 days, the corneum papillae were present in all four sizes of laminae. The histodifferentiation of the lamina propia-submucosa, tunica muscularis and serosa showed patterns of development similar to those reported for the rumen and reticulum of red deer. The omasum of red deer during prenatal life, especially from 67 days of gestation, was shown to be an active structure with full secretory capacity. Its histological development, its secretory capacity (detected by the presence of neutral mucopolysaccharides) and its neuroendocrine nature (detected by the presence of positive non-neuronal enolase cells and the neuropeptides vasoactive intestinal peptide and neuropeptide Y) were parallel to the development of the rumen and the reticulum. However, its prenatal development was later than that of the omasum in sheep, goat and cow