Dogs can be a potential risk for future influenza pandemic

Dogs are a potential reservoir for a future influenza pandemic, according to a study published in the journal mBio. The study demonstrated that influenza virus can jump from pigs into canines and that influenza is becoming increasingly diverse in canines.

"The majority of pandemics have been associated with pigs as an intermediate host between avian viruses and human hosts. In this study, we identified influenza viruses jumping from pigs into dogs," said study investigator Adolfo García-Sastre, PhD, director of the Global Health and Emerging Pathogens Institute and principal investigator, Center for Research on Influenza Pathogenesis (CRIP), Icahn School of Medicine at Mt. Sinai, New York City.

Influenza can jump among animal reservoirs where many different strains are located; these reservoirs serve as mixing bowls for the genetic diversity of strains. Pandemic influenza occurs when viruses jump from animal reservoirs to humans; with no prior exposure to the virus, most people do not have immunity to these viruses. The main animal hosts for influenza are wild birds, poultry and other domestic birds in a species pack; swine; and horses. Some of the viral genes from the 2009 pandemic H1N1 virus originated in birds, from an avian virus that jumped to pigs, exchanged some of its genes with previously circulating swine viruses and then jumped from pigs into humans. Birds and swine are major reservoirs of viral genetic diversity, whereas equines and canines have historically been restricted to one or two stable influenza A viruses lineages with no or very limited transmission to humans.

Fifteen years ago, researchers documented an influenza virus in a horse jumping into a dog, and this created the first circulating canine influenza viruses. Five years ago, researchers identified an avian-origin H3N2 canine influenza virus circulating in farmed dogs in Guangdong, China.

"In our study, what we have found is another set of viruses that come from swine that are originally avian in origin, and now they are jumping into dogs and have been reassorted with other viruses in dogs. We now have H1N1, H3N2, and H3N8 in dogs. They are starting to interact with each other. This is very reminiscent of what happened in swine ten years before the H1N1 pandemic."

Specifically, in the new study, the researchers sequenced the complete genomes of 16 influenza viruses obtained from canines in Southern China (Guangxi autonomous region) during 2013-2015. Other key study collaborators included Martha Nelson, PhD, a specialist in phylogenetic analysis and transmission reconstruction at CRIP, and Ying Chen, PhD, an influenza surveillance specialist who brought the samples from China. The researchers found that the genomes contained segments from three lineages that circulate in swine in China: North American triple reassortant H3N2, Eurasian avian-like H1N1, and pandemic H1N1. In addition, the swine-origin H1N1 viruses were transmitted onward in canines and reassorted with the CIV-H3N2 viruses that circulate endemically in Asian dogs, producing three novel reassortant CIV genotypes (H1N1r, /H1N2r, and H3N2r).

The viruses in the study were collected primarily from pet dogs presenting with respiratory symptoms at veterinary clinics. Dogs in certain regions of China, including Guangxi, are also raised for meat and street dogs roam freely, creating a more complex ecosystem for canine influenza virus transmission. "The new virus we have identified in our study is H1N1, but it comes from swine and is of avian origin, so it is different antigenically from the new H1N1s that were seen in the pandemic and a different origin as the previous H1N1 seen in humans," said Dr. García-Sastre.

Future studies will focus on characterizing the virus further and assessing, using human sera, whether humans have existing immunity against canine H1N1 or not. "If there is a lot of immunity against these viruses, they will represent less of a risk, but we now have one more host in which influenza virus is starting to have a diverse genotypic and phenotypic characteristics, creating diversity in a host which is in very close contact to humans," said Dr. García-Sastre. "The diversity in dogs has increased so much now that the type of combinations of viruses that can be created in dogs represent potential risk for a virus to jump to a dog into a human."

The researchers say it is time to think about ways to restrict the circulation of the influenza virus in dogs. The United States is free of avian influenza because every time avian influenza has been detected in poultry in this country, the chickens or turkeys are culled and eliminated from circulation," said Dr. García-Sastre. "There are attempts to restrict influenza virus in pigs through vaccination and one could consider vaccination for dogs."

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Materials provided by American Society for Microbiology.

Great tit birds have as much impulse control as chimpanzees

Biologists at Lund University in Sweden have in a recent study shown that the great tit, a common European songbird, has a tremendous capacity for self-control. Up to now, such impulse control has been primarily associated with larger cognitively advanced animals with far larger brains than the great tit. According to the new results, the great tits' ability for self-control is almost the same as that of ravens and chimpanzees.

The biologists placed food in a small translucent cylinder. The great tits that started pecking at the cylinder to get to the food failed the test as the behaviour was considered an impulsive act. Those that, on the other hand, moved to an opening in the cylinder and thereby were able to access the food without pecking at the cylinder wall passed the test.

The results show that the great tits did the right thing and succeeded in eight of the first ten attempts, i.e. 80 per cent of the time. This is better than most other animals tested and is almost on a par with "intelligent" animals such as ravens and chimpanzees.

"It's amazing that a bird with such a small brain has this type of self-control. The brain volume of a great tit corresponds to 3 per cent of a raven's brain and 0.1 per cent of a chimpanzee's," says Anders Brodin, professor at the Department of Biology.

The study was conducted by Anders Brodin, in collaboration with colleagues Utku Urhan and Emil Isaksson. A few years ago, these Lund University biologists discovered another ability of great tits -- an unusually high ability to learn and to remember by observing.

That study showed that great tits can sit and observe at a distance, and memorise where species that store food hide their treats. The study also showed that females generally outperform their male counterparts in this respect. In this study, the great tits were compared with their close relatives, the marsh tit and the willow tit. Unlike the marsh and willow tits, great tits do not store food to survive the winter. Instead, they can observe where their relatives hide their food and subsequently steal it.

"Great tits are very resourceful small birds. Now we know that they also have great self-control and can handle their impulses when they want to gain access to a reward such as food," says Anders Brodin.

Dogs proven to recognize themselves through precise sense of smell

A new study published in the journal Behavioural Processes recently demonstrated a dog’s acute sense of smell was enough to make the animal recognize itself.

As part of the study, a team of researchers at the Barnard College in New York City examined 36 domestic dogs accompanied by their owners. The dogs were presented three urine samples: one was of their won, a second was that of other dogs, and a third one was their own sample but was modified.

The scientists observed how long the dogs took to examine the urine samples. The research team also assessed whether the animals would be able to distinguish their own urine even if it was already modified with an additional odor.

The experts confirmed that the dogs were able to identify their own urine samples. According to the scientists, the findings support the notion of self-awareness among the animals. The results also underscore the need to shift from human-focused idea to species-specific approach in testing self-awareness across various animal specifies.

“The sniff test of self-recognition (STSR) even when applied to multiple individuals living in groups and with different ages and sexes, provides significant evidences of self-awareness in dogs, and can play a crucial role in showing that this capacity is not a specific feature of only great apes, humans and a few other animals, but it depends on the way in which researchers try to verify it,” lead researcher Dr. Alexandra Horowitz told Science Daily online.

Recent findings support previous hypothesis

The results of the recent study coincide with an experiment conducted last year. The hypothesis, proposed by Professor Roberto Cazzolla Gatti of the Biological Institute of Tomsk State University in Russia, demonstrates how sniffing can be a form of self-recognition among dogs.

Dogs, along with other animals — such as  several species of monkeys, giant pandas, sea lions, and birds — are known to fail at self-recognition as measured through the mirror test. According to the professor, the ability to instantly recognize one’s own image is particularly rare in the animal kingdom.

The expert said that dogs have previously shown no interest in looking at the mirror except to sniff and urinate around the object. The professor also noted that canines in general have high levels of cognitive complexity, but previous attempts to demonstrate their capacity to recognize themselves have been inconclusive.

“This sniff-test could change the way some experiments on animal behavior are validated. I believe that dogs and other animals, being much less sensitive to visual stimuli with respect to what, for example, humans and many apes are, cannot pass the mirror test because of the sensory modality chosen by the investigator to test the self-awareness and this in not, necessarily, due to the absence of this cognitive ability in some animal species,” Professor Roberto Cazzolla Gatti wrote in his researcher paper last year.

The professor also stressed that older dogs spent more time sniffing their urine, suggesting that self-awareness through scent-related cues may be dependent on age. The findings may be used in a variety of other animals including bats or moles, the expert said.

Sources include:

ScienceDaily.com

DailyMail.co.uk