Are Underweight Shelter Dogs More Likely to Display Food Aggression toward Humans?

It is commonly believed that underweight or emaciated dogs are predisposed to food aggression toward humans. Each year, the American Society for the Prevention of Cruelty to Animals (ASPCA) receives hundreds of dogs from criminal cruelty cases. The dogs range from emaciated to overweight. We analyzed existing data from 900 such dogs to examine the relationship between body condition score and food and chew item aggression toward humans. Across all types of cruelty cases, 9.2% of dogs were aggressive over the food, chew, or both, which is a lower prevalence than that previously reported among shelter dogs. Dogs from cruelty cases originating in New York City were more likely to show aggression over food (z = 3.91, p < 0.001) and chew items (z = 2.61, p = 0.01) than dogs from large-scale cruelty cases, although it is unclear why. Female dogs were less likely to show food (z = -3.75, p < 0.001) and chew item (z = -2.25, p = 0.02) aggression compared to males. Underweight dogs were not more likely to display food aggression, but when they did, the aggression was no more severe than that of normal-weight dogs (Fisher's exact tests = 0.41 and 0.15 for the Food Bowl and Chew Item scenarios, respectively). Breed type was not a significant predictor of aggression. Canine food aggression does not appear to be an aberrant behavior caused by a history of food scarcity but may be related to biological factors such as sex. These findings could prove useful for animal behavior subject matter experts testifying in court or consulting on cruelty cases, as they could speak with scientific validity to the question of whether there is a link between previous food scarcity and the likelihood of food aggression in dogs.

Myomesin is part of an integrity pathway that responds to sarcomere damage and disease.

The structure and function of the sarcomere of striated muscle is well studied but the steps of sarcomere assembly and maintenance remain under-characterized. With the aid of chaperones and factors of the protein quality control system, muscle proteins can be folded and assembled into the contractile apparatus of the sarcomere. When sarcomere assembly is incomplete or the sarcomere becomes damaged, suites of chaperones and maintenance factors respond to repair the sarcomere. Here we show evidence of the importance of the M-line proteins, specifically myomesin, in the monitoring of sarcomere assembly and integrity in previously characterized zebrafish muscle mutants. We show that myomesin is one of the last proteins to be incorporated into the assembling sarcomere, and that in skeletal muscle, its incorporation requires connections with both titin and myosin. In diseased zebrafish sarcomeres, myomesin1a shows an early increase of gene expression, hours before chaperones respond to damaged muscle. We found that myomesin expression is also more specific to sarcomere damage than muscle creatine kinase, and our results and others support the use of myomesin assays as an early, specific, method of detecting muscle damage.

Wnt signaling and polarity in freshwater sponges.

BACKGROUND: The Wnt signaling pathway is uniquely metazoan and used in many processes during development, including the formation of polarity and body axes. In sponges, one of the earliest diverging animal groups, Wnt pathway genes have diverse expression patterns in different groups including along the anterior-posterior axis of two sponge larvae, and in the osculum and ostia of others. We studied the function of Wnt signaling and body polarity formation through expression, knockdown, and larval manipulation in several freshwater sponge species. RESULTS: Sponge Wnts fall into sponge-specific and sponge-class specific subfamilies of Wnt proteins. Notably Wnt genes were not found in transcriptomes of the glass sponge Aphrocallistes vastus. Wnt and its signaling genes were expressed in archaeocytes of the mesohyl throughout developing freshwater sponges. Osculum formation was enhanced by GSK3 knockdown, and Wnt antagonists inhibited both osculum development and regeneration. Using dye tracking we found that the posterior poles of freshwater sponge larvae give rise to tissue that will form the osculum following metamorphosis. CONCLUSIONS: Together the data indicate that while components of canonical Wnt signaling may be used in development and maintenance of osculum tissue, it is likely that Wnt signaling itself occurs between individual cells rather than whole tissues or structures in freshwater sponges.

The Impact of Excluding Food Guarding from a Standardized Behavioral Canine Assessment in Animal Shelters.

Many shelters euthanize or restrict adoptions for dogs that exhibit food guarding while in the animal shelter. However, previous research showed that only half the dogs exhibiting food guarding during an assessment food guard in the home. So, dogs are often misidentified as future food guarders during shelter assessments. We examined the impact of shelters omitting food guarding assessments. Nine shelters conducted a two-month baseline period of assessing for food guarding followed by a two-month investigative period during which they omitted the food guarding assessment. Dogs that guarded their food during a standardized assessment were less likely to be adopted, had a longer shelter stay, and were more likely to be euthanized. When the shelters stopped assessing for food guarding, there was no significant difference in the rate of returns of food guarding dogs, even though more dogs were adopted because fewer were identified with food guarding behavior. Additionally, the number of injuries to staff, volunteers, and adopters was low (104 incidents from a total of 14,180 dogs) and did not change when the food guarding assessment was omitted. These results support a recommendation that shelters discontinue the food guarding assessment.

Relationship Between Scarring and Dog Aggression in Pit Bull-Type Dogs Involved in Organized Dogfighting.

When pit bull-type dogs are seized in an investigation of organized dogfighting, heavily scarred dogs are often assumed to be highly dog aggressive due to a history of fighting. These dogs may be deemed dangerous and euthanized based on scarring alone. We analyzed our existing data on dogs seized from four dogfighting investigations, examining the relationship between the dogs' scars with aggression towards other dogs. Scar and wound data were tallied in three body zones where dogfighting injuries tend to be concentrated. Dog aggression was assessed using a model dog and a friendly stimulus dog in a standardized behavior evaluation. Scarring and dog aggression were significantly related, more strongly among male (Fisher's Exact p < 0.001) than female dogs (Fisher's Exact p = 0.05). Ten or more scars in the three body zones was a reasonable threshold with which to classify a dog as high risk for dog aggression: 82% of males and 60% of females with such scarring displayed dog aggression. However, because many unscarred dogs were dog aggressive while some highly scarred dogs were not, we recommend collecting behavioral information to supplement scar counts when making disposition decisions about dogs seized in dogfighting investigations.

Still Heart Encodes a Structural HMT, SMYD1b, with Chaperone-Like Function during Fast Muscle Sarcomere Assembly.

The vertebrate sarcomere is a complex and highly organized contractile structure whose assembly and function requires the coordination of hundreds of proteins. Proteins require proper folding and incorporation into the sarcomere by assembly factors, and they must also be maintained and replaced due to the constant physical stress of muscle contraction. Zebrafish mutants affecting muscle assembly and maintenance have proven to be an ideal tool for identification and analysis of factors necessary for these processes. The still heart mutant was identified due to motility defects and a nonfunctional heart. The cognate gene for the mutant was shown to be smyd1b and the still heart mutation results in an early nonsense codon. SMYD1 mutants show a lack of heart looping and chamber definition due to a lack of expression of heart morphogenesis factors gata4, gata5 and hand2. On a cellular level, fast muscle fibers in homozygous mutants do not form mature sarcomeres due to the lack of fast muscle myosin incorporation by SMYD1b when sarcomeres are first being assembled (19hpf), supporting SMYD1b as an assembly protein during sarcomere formation.

Adapting to the human world: dogs' responsiveness to our social cues.

Dogs are more skilful than a host of other species at tasks which require they respond to human communicative gestures in order to locate hidden food. Four basic interpretations for this proficiency surface from distilling the research findings. One possibility is that dogs simply have more opportunity than other species to learn to be responsive to human social cues. A different analysis suggests that the domestication process provided an opening for dogs to apply general cognitive problem-solving skills to a novel social niche. Some researchers go beyond this account and propose that dogs' co-evolution with humans equipped them with a theory of mind for social exchanges. Finally, a more prudent approach suggests that sensitivity to the behaviours of both humans and conspecifics would be particularly advantageous for a social scavenger like the dog. A predisposition to attend to human actions allows for rapid early learning of the association between gestures and the availability of food.

Audit of a pathway for childhood idiopathic constipation.

Constipation is a common condition in developed and industrialised nations. Although its exact prevalence is unknown it is estimated that between five and thirty per cent of the U.K. population suffer with it, depending on the criteria used for diagnosis (Candelli, 2001). Constipation that cannot be explained by any underlying abnormalities is known as idiopathic constipation.

Effects of aerobic exercise training on the protein kinase B (PKB)/mammalian target of rapamycin (mTOR) signaling pathway in aged skeletal muscle.

The protein kinase B (PKB)/mammalian target of rapamycin (mTOR) signaling pathway is thought to play a critical role in the regulation of protein synthesis and skeletal muscle mass. The purpose of the present study was to determine the effects of voluntary wheel running on the PKB/mTOR signaling pathway in muscles from aged mice (20-22 months). The total levels of mTOR were 65% higher in gastrocnemius muscles from aged mice subjected to wheel running compared to aged sedentary mice (p-0.002) PKB phosphorlation on Ser473 was 45% higher in gastrocnemius muscles from aged mice subjected to wheel running compared to aged sedentary mice (p=0.01) The total abundance of PKB was 50% higher in gastrocnemius muscles from wheel running mice compared to aged controls (p=0.005). Three months of wheel running did not alter the total amount of p70 S6K in gastrocnemius muscle. Protein synthesis, as assessed by [(14)C]phenylalanine incorporation into protein was significantly higher in soleus muscles from aged mice subjected to wheel running compared to aged sedentary mice (p-0.001) These findings indicate the aerobic exercise training may attenuate the age-related decline in protein synthesis, a process that appears to be due, in part, to increases in mTOR and PKB.

GFP in living animals reveals dynamic developmental responses to ecdysone during Drosophila metamorphosis.

Studies of Drosophila metamorphosis have been hampered by our inability to visualize many of the remarkable changes that occur within the puparium. To circumvent this problem, we have expressed GFP in specific tissues of living prepupae and pupae and compiled images of these animals into time-lapse movies. These studies reveal, for the first time, the dynamics and coordination of morphogenetic movements that could only be inferred from earlier studies of dissected staged animals. We also identify responses that have not been described previously. These include an unexpected variation in some wild-type animals, where one of the first pairs of legs elongates in the wrong position relative to the second pair of legs and then relocates to its appropriate location. At later stages, the antennal imaginal discs migrate from a lateral position in the head to their final location at the anterior end, as leg and mouth structures are refined and the wings begin to fold. The larval salivary glands translocate toward the dorsal aspect of the animal and undergo massive cell death following head eversion, in synchrony with death of the abdominal muscles. These death responses fail to occur in rbp(5) mutants of the Broad-Complex (BR-C), and imaginal disc elongation and eversion is abolished in br(5) mutants of the BR-C. Leg malformations associated with the crol(3) mutation can be seen to arise from defects in imaginal disc morphogenesis during prepupal stages. This approach provides a new tool for characterizing the dynamic morphological changes that occur during metamorphosis in both wild-type and mutant animals.

Multicultural psychology: bringing together gender and ethnicity.

This article suggests that just as gender studies should not proceed without consideration of the various contexts in which men and women behave, similarly multicultural psychology should recognize gender, among other characteristics in the populations examined. Focusing on ethnic group women, who are understudied, develops this theme. Two arguments are proposed: (a) that gender must be recognized as impinging on every aspect of psychological research and practice, and (b) that gender should be considered an aspect of culture, just as ethnicity now is. The literature in psychology is reviewed to demonstrate how erroneous beliefs and exclusion operate to minimize examination of ethnicity and gender. Finally, a call to advocacy is made for attention to complexity.

Effect of age on skeletal muscle proteolysis in extensor digitorum longus muscles of B6C3F1 mice.

The purpose of this study was to determine if age-related muscle atrophy is associated with an increased rate of protein degradation in extensor digitorum longus (EDL) muscles from young (YG; 2-4 months), middle-aged (MA; 12-17 months), and aged (AG; 22-24 months) B6C3F1 mice. EDL muscles from AG mice weighed less than EDL muscles from MA mice (p =.01). EDL muscles from MA mice weighed more than EDL muscles from YG mice (p =.02). The rate of protein degradation, as assessed by tyrosine release during in vitro incubations, was higher in EDL muscles from AG mice than it was in those from MA mice (p =.03). The rate of protein degradation was higher in EDL muscles from YG mice than it was in those from MA mice (p =.04). An inverse relationship existed between muscle mass and protein degradation (r = -.67; p =.0001). We conclude that skeletal muscle protein degradation rates decrease with maturation and increase with advancing age.

A CD40 Signalosome anchored in lipid rafts leads to constitutive activation of NF-kappaB and autonomous cell growth in B cell lymphomas.

B cell lineage non-Hodgkin's lymphomas (NHL-B) are neoplastic B cells that show dysregulated B lymphocyte growth characteristics. Unlike normal B cells, aggressive NHL-B cells show constitutive expression of nuclear NF-kappaB by maintaining an assembled, scaffold-like signaling platform, called a Signalosome within the lipid raft microdomain, extending from the cell membrane. The CD40 Signalosome appears to be initiated through autochthonous production and cognate binding of CD154 (CD40L, gp39) to CD40 by the lymphoma cell. Constitutive expression of NF-kappaB in NHL-B can be downregulated by treatment with antibodies to CD40 or CD154 that disrupt Signalosomes, inhibit lymphoma cell growth, and induce cell death. CD40 Signalosomes may provide a potentially vulnerable target for therapeutic intervention in NHL-B cells.