Origin, Phylogeny and Natural Behavior of Mice: What is Their Influence on Welfare During their Maintenance in the House Facilities?

The mouse is the species most used for didactic and scientific purposes. Given the ethical principles, Brazil´s legislation and normatives, it is recommended that the welfare of mice in the laboratory be linked to the promotion of conditions in which the animal can express its natural behavior. However, in the literature, information on the natural behavior of mice is limited. Thus, the objective of this work was to conduct a study on several genealogical and phylogenetic aspects. Origin of the mouse was 14 million years ago by rodents that inhabited the region between India and Pakistan and spawned the genus Mus, the subgenus Mus, the species Mus musculus and several subspecies. This speciation was probably related to its migration, colonization and commensal relationship with humans. Thus, a characteristic that stands out in the mouse is its adaptive capacity and social flexibility, always seeking reproductive success through the provision of food, territorialism, and formation of small groups, usually polygamous. Thus, we can say that the mouse kept in its genetics characteristics of its wild behavior, such as competition and interpersonal aggressiveness, as well close relationship with humans and its high adaptability to new environments, provided mainly food supply. In conclusion, we believe that its welfare is directed towards respecting the natural characteristics and biological evolution of the mouse, for example, stress is part of the animal’s physiology, its high adaptability and commensalism with humans. However, raising the welfare of mice in the house facilities should be accomplished by developing methodologies that enable the animal to demonstrate its preference (or choice) for space, food, floor, handling and other management procedures as animal reproduction or biological tests.

applying ethical principles and legal regulation is primarily aimed at replacing animals with validated alternative methods that may replace their use. If this is not possible, the development of equipment, techniques and methodologies that can refine the use of animals should be emphasized, and all efforts should be related to the maintenance, promotion and elevation of animal welfare during biomedical assays [2]. In Brazil, our legal framework in the area of laboratory animal science, after 12 years in the National Congress, was the approval of Law N o .11.794 [2]. Through this law the National Council for Control of Animal Experimentation (CONCEA) was structured on 2015 [2]. Activities. Teaching or Scientific Research, in which it describes and guides animal welfare strategies in animal houses, such as care to consider for the welfare of rodents and lagomorphs [3,4]. In all this report, especially in RN N o 33, we emphasize that the relationship between the performance of procedures and the welfare of rodents and lagomorphs, in our case highlighting the Mus musculus biomodel, imparts in certain sections that: "It is essential to know the biology of the species, race, lineage to work with, since the basic needs (physical, emotional or behavioral) to be met are not the same for all animals." and "… promote the expression of speciesspecific natural behaviors and a decrease, if not the disappearance, of abnormal behaviors.It should be based on promoting a positive effect on the physical and psychological welfare of the animal " [3].
We emphasize that the excerpts "to know species biology (physical, emotional or behavioral)" and "promote the expression of species-specific natural behaviors and a decrease, if not disappearance, of abnormal behaviors" were the motivating factors of this work [3]. Our aim was based on the question: How to know the physical, emotional or behavioral needs and the possibility of the expression of species-specific natural behaviors in order to provide the welfare of mice in the house facilities? Thus, we carry out a detailed bibliographic from the mouse origin of the species and its phylogeny, the knowledge about its geographical distribution, its habitat and natural behavior until the beginning of the controlled creation for the use in the scientific assays so that we can demonstrate, through scientific results, how we can approach the physical, emotional and behavioral needs of the space-restrain mouse in our animal house facilities and during biomedical trials by maintaining or enhancing animal welfare.

Mouse: Origin of the Species
Some authors state that there is a divergence in paleontological and phylogenetic studies regarding time estimates when dealing with lineage diversification rates, evolutionary patterns and historical biogeography, among other factors [5,6]. Fossil data is the most common type of paleontological calibration used to estimate the time period of the descendant in the phylogenetic tree.
However, as described by Graur & Martim [7], Dos Reis & Yang [8] the incorporation of fossils for phylogenetic tree structuring can present difficulties such as: i.
The integrity of the fossil record ii.
The accuracy of the age of fossils iii.
The correction of the placement in the phylogenetic fossil calibration [7,8] Kimura et al. [9] Describe that for a more reliable determination of time and fossil descendants may be the use of a methodology based on the study of the first upper molar teeth (M1). In this study the researchers used murine fossil specimens collected from northern Pakistan and examined by digitizing dental images and using tests such as Cochran-Mantel-Haenszel (CMH) and Goodman-Kruskal's gamma [9]. The questions evaluated in the teeth were the change in frequency distribution of the size and inclination of the region called metacone in relation to paracone and the inclination of the respective axes [9]. However, [10] used a refined set of fossil calibrations that were used to reconstruct a murine family dated phylogeny using a multilocus dataset method (six nuclear and nine mitochondrial gene fragments) spanning 161 species and 82 murine genera from four existing subfamilies (Deomyinae, Gerbillinae, Lophiomyinae and Murinae) [10].
Therefore, regarding muridae family speciation, several types of genetic markers can be applied to peripheral populations: i. C-band chromosomal patterns [11,12].
ii. Several nuclear autosomal genes studied by protein electrophoresis or by RFLP DNA [13,14]. iii.
vii. Some sequences of the Y chromosome [19] and mainly mitochondrial DNA [20].
The oldest known fossil murine, Antemus chinjiensis [9,21], was recorded in the region called Indo-Pakistan in the middle Miocene 14Ma (Millions of years ago), followed by Progonomys

Habitat and Natural Behavior
One of the main characteristics related to the habitat and natural behavior of the mouse is its commensal relationship with humans. But commensalism must be accepted as the only one theory [23]. In its origin, the genus Mus was related to arid climatic  This aggressiveness is so imposing that this subspecies is able to dominate males M. m. musculus [29].
Aggressive behavior is a hereditary trait, with complex genetic, epigenetic and environmental determinism. In addition, aggressive behavior is likely to be subject to natural and sexual selection [30].
Variation in the intensity of aggressiveness between subspecies may be the result of environmental conditions (territory, food and reproduction). This fact highlights another striking feature in the natural behavior of mice that is adaptability and, more specifically, social flexibility and has been suggested as a possible explanation for their evolutionary success. It is suggested that the emergence of commensal behavior with humans occurred in the search for a safe environment and the supply of food, which is constantly being supplied, thus reducing competition between subspecies, predators and climate pressures [31]. Food disponibility promotes high population density, there is an organization of access to food (developing omnivorous habits with varied diets, including grains, seeds and insects) through a hierarchical population structure [27]. Interestingly, female mice prefer males who have higher levels of these pheromones [34]. Soini et al. [35], demonstrated that the absence of thiazoline in M. spicilegus, which is a non-commensal, where it can be studied from an ancestor that branched into several species, such as the rat, gerbil and others [9]. While the mouse in its pedigree continued to improve its characteristics, under intense In our study we can point out some points that will be important to reflect on your welfare in animal houses:

i.
We can consider these animals prepared physiologically for stress situations, especially the fight and flight system.
It is important to maintain a routine and conditioning of management and procedures not to make stress harmful to the animal. ii.
They have a tremendous ability to adapt to harsh environments and conditions as long as there is time for them to adapt and maintain their routine. iii.
Commensal behavior with humans is extremely beneficial for the mouse. Initially for the supply of food, but we can also observe that although stealthy, the proximity to the human increases their social flexibility.
So, what we can say is that the relationship with humans was a path that these animals found given the ease of access to food and their ability to hide and escape risk situations. In addition, they are naturally non-isogenic animals with a natural control of variability and genetic perpetuation carried out through groups and the integration of new members to the group, mainly males and with high turnover, due to the low life expectancy of the dominant group. We may reflect that the welfare of this animal is much more tied to its own choices or preferences than when we try to relate our welfare state to that of this animal. Furthermore, we cannot compare our stress with the stress of this animal. It is an animal that already has a system, we can say, in stress. At this point, we believe that comes your ability to adapt. The suffering and discomfort of this animal start from the space restriction and its impossibility to move or seek a place of its choice (we believe more stable and safer). Therefore, we must look for ways to raise the welfare of this space-constrained animal so that its adaptation is close as possible to its preference and it is our obligation to maintain a routine and management always close to what the animal is adapted to avoiding the sudden changes as Ambiental variation in the house facilities.
We have learned from the genealogy of these animals several interesting features, such as their great strength and adaptability to selective pressures. His commensal relationship as a human being that completely changes his behavior, however, comes from his need for access to food, but we can say that his relationship with the human being does not cause suffering or stress to the mouse.