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The behaviour of a pack of 14 Siberian huskies dogs of different sex and ages was observed. Based on observation of different dominant, submissive and affiliate behaviours of each dog, pack hierarchy was described. Behavioural patterns and frequencies of different behaviours were compared with those, previously described in wild wolves. Social structure and linear hierarchy proved very similar, whereas there were some differences as far as single specimens are concerned. The alpha male did not display overt aggression towards the omega male, and he was - at least to some extend - involved in controlling and ceasing conflicts. Husky pack displayed several behaviours, common in wolves, yet seldom reported in domestic dog, e.g. feeding area marking, leg lifting during urination in females and full range of vocal patterns.
Litter size, puppy weight at birth and growth rates in different breeds of dogs. In this study was compare litter size, sex distribution and body weight at birth and during first 7 weeks of life in puppies 7 breeds, which can be classified into 4 size groups: miniature: Yorkshire Terrier, small: Shetland Sheepdog, Welsh Corgi Pembroke medium: Polish Mountain Hound, Bouvier des Flandres, large: Great Dane and Newfoundland. In analyzing growth rates in different breeds was used the average weights at subsequent weeks were calculated as percentages of adult weights and calculated as multiplicity of birth weight. All results were statistically tested with Anova and Bonferroni Tests. Litter size was bigger consequ­ently with adult dogs body mass and difference between breeds were significant. Sex distribution was found significantly uneven in Yorkshire Terrier breed - the number of females was almost twice as big as the number of males. Body weight at birth compared to adult weight of respective breed was found significantly different among the breeds. This relation was highest in the miniature Yorkshire Terrier and small breeds, and lowest in large breeds: the Great Dane and the Newfoun­dland. Growth rate as percentage of adult weight in consecutive weeks of age was greatest in the smallest breed - the Yorkshire Terrier, only slightly lower in small, and distinctly lower in medium-sized and large breeds. Growth rate as multiplicity of birth weight was fasted in medium breed Polish Hound and large Great Dane, slowest in Yorkshire.
Occurrence of behavioural disorders in domestic cats. 269 cat owners was aimed at collecting information on abnormal/undesired behaviours of their pets. Based on this information, influence of sex, breed, age, origin, age at purchase/adoption and living conditions (number of cats, presence of other animals and/or children) on respective behaviours was studied. Results were analyzed with Chi² test and V-Kramer coefficient was calculated to establish level of correlations between different features. Abnormal/undesirable behaviours were reported in 73% of cats. 50% of them would scratch walls and furniture, and this behaviour was influenced by age at purchase/adoption, absence of other animals, and age of children in the family. 28.6% of cats showed urination/defecation in random places and this was influenced by age (more common in older animals), reproductive status (more frequent in neutered animals, irrespective of their sex) and presence of other animals. Aggression towards other cats occurred in 20% of animals, most of them over 8 years of age and it was also far more common in cats allowed to spent at least some time outdoor. Aggression towards animals of other species was found in 10% of cats, significantly more often in females and cats of both sexes roaming free. Other abnormal//undesirable behaviours were: destruction (8%), aggression towards people (significantly more frequent in households with children), excessive grooming (2.6%) and autoaggression (1.9%).
Long-term selection for body weight, which affecting changes in life span and time of puberty, has resulted different reproductive strategy in mice divergently selected for body weight at the 21st day of age. Heavy mice (C) are typically rapidly maturing animals, with a shorter but more intense reproductive period. Light mice (L) are more long-lived so that mature later than C mice, Due to the longer period of reproduction L mice are capable of more litters, which are also less numerous. Moreover, long-term selection may changes of mice. L mice showed lower activity in the open field test. Light mice are more susceptible to stress, and they have higher excitability, than heavy mice.
Studies in many countries have proven that the company of a dog has a positive influence on human relations as well on the emotional, mental and physiological status of human beings. Dog owners are generally healthier and more physically active, and therefore less often require professional medical assistance. However, several problems must be taken into consideration, the most serious being dog bites. Biting incidents have led to regulations ranging from mandatory use of a lead in public places to a ban on ‘aggressive breeds’, though studies on risk factors have not found these breeds to be most frequently involved in dog biting inci-dents. In Poland mixed breeds have been shown to be the most likely culprits, which may be attributed to their prevalence (65%) in the local population. The majority of incidents take place on the dog’s territory. Studies analysing the age of victims have shown a higher per-centage of adults (84%), primarily women (56%), whereas in the USA 60-70% of victims are children. The latter cases may be more dangerous due to the location of the bite. According to numerous authors, children are usually bitten during interactions with their families’ or neighbours’ dogs, so that regulations remain Ineffective. Instead, proper socialization and training of dogs, together with educational programmes addressed to children and their guardians, seem to be the most effective preventive measures.
In order to identify the possible mutations in exon 5 RPE65 gene in the Polish population of French sheepdogs - briards - we have studied 51 dogs of this breed (26 males and 25 females). The population studied consisted of about 80% of the key breeding stock animals in Poland. PCR reaction was performed after isolation of genomic DNA. The resulted product was - with no exception - of 107bp length, suggesting that no 4 bp deletion (485 del AAGA) occurred. PCR-SSCP reaction was performed to search for any possible mutations, resulting in three SSCP patterns obtained: a, b and c at 0.157; 0.549 and 0.294 frequency, respectively. After DNA sequencing we were able to prove that all specimens, showing pattern c were heterozygous and combined patterns a and b. Only slight single nucleotide polymorphism (SNPs) of RPE65 gene was detected. The difference found between both DNA sequences studied was restricted to 459 nucleotide (T459C) of RPE65 gene. When both sequences studied were compared to those, already published in GeneBank, we found they differed in 432 (T432C), 459 (T459C) and 505 (T505C) nucleotides of RPE65 gene. However, none of those differences resulted in either of (N135N), (Y144Y) and (L160L) protein product change. Having conducted the fore mentioned study, we come to conclusion that neither affected animals, nor carriers of mutated RPE65 gene are present in the Polish briard population.
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