Canine genome-wide association study identifies as an obesity gene in dogs and humans.

Obesity is a heritable disease, but its genetic basis is incompletely understood. Canine population history facilitates trait mapping. We performed a canine genome-wide association study for body condition score, a measure of obesity, in 241 Labrador retrievers.

Low resting metabolic rate and increased hunger due to β-MSH and β-endorphin deletion in a canine model.

Mutations that perturb leptin-melanocortin signaling are known to cause hyperphagia and obesity, but energy expenditure has not been well studied outside rodents. We report on a common canine mutation in pro-opiomelanocortin (), which prevents production of β-melanocyte-stimulating hormone (β-MSH) and β-endorphin but not α-MSH; humans, similar to dogs, produce α-MSH and β-MSH from the propeptide, but rodents produce only α-MSH. We show that energy expenditure is markedly lower in affected dogs, which also have increased motivational salience in response to a food cue, indicating increased wanting or hunger.

"Feel the Force"-Prevalence of Subjectively Assessed Saddle Fit Problems in Swiss Riding Horses and Their Association With Saddle Pressure Measurements and Back Pain.

Ill-fitting saddles can impair the well-being and performance of horses. Saddle fit is generally assessed subjectively by a trained professional or with an electronic saddle pressure mat, but little is known about the agreement between both methods. The study aims were (1) to assess the prevalence of saddle fit issues in a riding sound Swiss horse population, (2) to investigate how well the subjective assessment correlates with objectively measured pressure magnitude and distribution under the saddle during riding, and (3) how well both correlate with back pain of the horse.

Reliable and clinically applicable gait event classification using upper body motion in walking and trotting horses.

Objectively assessing horse movement symmetry as an adjunctive to the routine lameness evaluation is on the rise with several commercially available systems on the market. Prerequisites for quantifying such symmetries include knowledge of the gait and gait events, such as hoof to ground contact patterns over consecutive strides. Extracting this information in a robust and reliable way is essential to accurately calculate many kinematic variables commonly used in the field.

Riding Soundness-Comparison of Subjective With Objective Lameness Assessments of Owner-Sound Horses at Trot on a Treadmill.

Lameness is a symptom indicative of pain or injury of the locomotor apparatus. Lame horses generally should not be ridden. However, owners' ability to assess lameness has been questioned.

Husbandry, Use, and Orthopedic Health of Horses Owned by Competitive and Leisure Riders in Switzerland.

The use of horses in competitive sports receives increasing criticism from the public, mainly due to the potential for injury. However, it is unclear if orthopedic and other health issues are more common in competition horses than those in leisure horses. The aim of this study was to assess husbandry, use, and orthopedic health in Swiss riding horses and to compare these aspects between horses owned by self-identified competitive riders (CR) and leisure riders (LR) in Switzerland.

Ingestive mastication in horses resembles rumination but not ingestive mastication in cattle and camels.

Horses achieve a higher degree of particle size reduction through ingestive mastication than functional ruminants. We characterized mastication using chew-monitoring halters (RumiWatch) in six domestic horses, cattle, and Bactrian camels each. All animals were offered grass hay of the same batch for 15 min.

Influence of ruminal methane on digesta retention and digestive physiology in non-lactating dairy cattle.

Enteric methane (CH4) production is a side-effect of herbivore digestion, but it is unknown whether CH4 itself influences digestive physiology. We investigated the effect of adding CH4 to, or reducing it in, the reticulorumen (RR) in a 4×4 Latin square experiment with rumen-fistulated, non-lactating cows, with four treatments: (i) control, (ii) insufflation of CH4 (iCH4), (iii) N via rumen fistula, (iv) reduction of CH4 via administration of bromochloromethane (BCM). DM intake (DMI), apparent total tract digestibility, digesta mean retention times (MRT), rumen motility and chewing activity, spot breath CH4 emission (CH4exhal, litre/kg DMI) as well as CH4 dissolved in rumen fluid (CH4RRf, µg/ml) were measured.

Methane production by two non-ruminant foregut-fermenting herbivores: The collared peccary (Pecari tajacu) and the pygmy hippopotamus (Hexaprotodon liberiensis).

Methane (CH4) production varies between herbivore species, but reasons for this variation remain to be elucidated. Here, we report open-circuit chamber respiration measurements of CH4 production in four specimens each of two non-ruminant mammalian herbivores with a complex forestomach but largely differing in body size, the collared peccary (Pecari tajacu, mean body mass 17kg) and the pygmy hippopotamus (Hexaprotodon liberiensis, 229kg) fed lucerne-based diets. In addition, food intake, digestibility and mean retention times were measured in the same experiments.

Digesta retention patterns of solute and different-sized particles in camelids compared with ruminants and other foregut fermenters.

The mean retention times (MRT) of solute or particles in the gastrointestinal tract and the forestomach (FS) are crucial determinants of digestive physiology in herbivores. Besides ruminants, camelids are the only herbivores that have evolved rumination as an obligatory physiological process consisting of repeated mastication of large food particles, which requires a particle sorting mechanism in the FS. Differences between camelids and ruminants have hardly been investigated so far.

Digesta kinetics in gazelles in comparison to other ruminants: Evidence for taxon-specific rumen fluid throughput to adjust digesta washing to the natural diet.

Digesta flow plays an important role in ruminant digestive physiology. We measured the mean retention time (MRT) of a solute and a particle marker in the gastrointestinal tract (GIT) and the reticulorumen (RR) of five gazelles and one dikdik species. Species-specific differences were independent from body mass (BM) or food intake.

Methane emission by adult ostriches (Struthio camelus).

Ostriches (Struthio camelus) are herbivorous birds with a digestive physiology that shares several similarities with that of herbivorous mammals. Previous reports, however, claimed a very low methane emission from ostriches, which would be clearly different from mammals. If this could be confirmed, ostrich meat would represent a very attractive alternative to ruminant-and generally mammalian-meat by representing a particularly low-emission agricultural form of production.

Testing the stages model in the adaptive radiation of cichlid fishes in East African Lake Tanganyika.

Adaptive radiation (AR) is a key process in the origin of organismal diversity. However, the evolution of trait disparity in connection with ecological specialization is still poorly understood. Available models for vertebrate ARs predict that diversification occurs in the form of temporal stages driven by different selective forces.

Methane emission by camelids.

Methane emissions from ruminant livestock have been intensively studied in order to reduce contribution to the greenhouse effect. Ruminants were found to produce more enteric methane than other mammalian herbivores. As camelids share some features of their digestive anatomy and physiology with ruminants, it has been proposed that they produce similar amounts of methane per unit of body mass.

Energy requirements and metabolism of the Phillip's dikdik (Madoqua saltiana phillipsi).

Basal metabolic rates in mammals are mainly determined by body mass, but also by ecological factors. Some mammalian species inhabiting hot, dry environments were found to have lower metabolic rates compared to temperate species. We studied energy metabolism in Phillip's dikdik (Madoqua saltiana phillipsi), a small antelope inhabiting xeric shrubland habitats in the Eastern 'horn' of Africa, and compared results to literature data.

Human-introduced long-term traditions in wild redfronted lemurs?

Behavioural traditions have only been described for a small subset of species, and the factors responsible for the maintenance of traditions over time are unclear. Redfronted lemurs are known to learn socially but traditions have not been described in the wild. We conducted a social diffusion experiment over three experimental years with artificial feeding boxes that could be opened in two different ways (pushing or pulling a door).

Retention of solutes and different-sized particles in the digestive tract of the ostrich (Struthio camelus massaicus), and a comparison with mammals and reptiles.

Ostriches (Struthio camelus) achieve digesta retention times, digesta particle size reduction and digestibilities equal to similar-sized herbivorous mammals, in contrast to some other avian herbivores. The sequence of digestive processes in their gastrointestinal tract, however, is still unexplored. Using two groups of four ostriches (mean body mass 75.