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The mating system of feral Sika deer (Cervus nippon) in the Manětín Forest (220 km2), Czech Republic, was studied from 1989 to 1993. The Sika were strictly nocturnal due to hunting pressure and continuous human harassment during daylight. We therefore monitored rutting activity by triangulating male Sika calls recorded from different sites, and also by counting Sika in open areas using a spot light. In all seasons, calling activity was unequally distributed over the area, usually concentrated in fields close to the forest. In 1989 the Sika established a lek. Later, the mating system changed to dispersed rutting stands. These rutting stands were occupied intermittently and were located in open pasture, mature forest, and in the boundaries between these two habitat types., Le système d’appariement de Cerfs Sika (Cervus nippon ) introduits dans la forêt de Manětín (220 km2), République tchèque, a été étudié de 1989 à 1993. Le Sika était strictement nocturne en raison des pressions de chasse et des dérangements continus par l’homme dans la journée. Les activités de rut ont été suivies par triangulation des cris des mâles en divers sites, ainsi que par comptage au phare des cerfs dans les zones ouvertes. Durant toutes les saisons, les activités vocales ne furent pas réparties uniformément sur la zone d’étude, étant généralement concentrées dans des champs proches de la forêt. En 1989, un lek fut constitué. Par la suite, il éclata en arènes dispersées. Ces arènes furent occupées par intermittence et étaient localisées tant dans les pâturages ouverts qu’en forêt mature et à l’interface de ces deux types d’habitat., Bartoš Luděk,Herrmann Hubert,Šiler Jiří,Losos Soběslav,Mikeš Jaroslav. Variation of mating systems of introduced sika deer. In: Revue d'Écologie (La Terre et La Vie), tome 53, n°4, 1998. pp. 337-345.

Fledgling behaviour and movement patterns throughout the post-fledging dependence period (PFDP), especially in relation to changing environmental conditions, have been rarely studied, despite the fact that this period is recognized as of crucial significance in terms of high mortality of juveniles. The PFDP can extend over quite a protracted period, particularly in birds of prey, and a knowledge of the movement patterns of individuals is fundamental for understanding mechanisms underlying survival, habitat use and dispersion. We radiotracked 39 fledglings of the Tengmalm's owl (Aegolius funereus) in two years with different availability of prey: 2010 (n = 29) and 2011 (n = 10) and obtained 1455 daily locations. Fledglings reached independence on average in 45 days after fledging in 2010 (n = 22) and 57 days in 2011 (n = 6). Within years, the most important measures influencing the distance moved from the nest box were age of fledglings and number of surviving siblings present. Individual home range size and duration of PFDP in particular were dependent on maximal number of siblings seen outside the nest box. In the season with low prey availability fledglings were observed at greater distances from the nest box than in the year with higher prey availability (mean distance: 350 m in 2010 and 650 m in 2011) and occupied larger home ranges (mean: 30.3 ha in 2010 and 57.7 ha in 2011). The main factor causing these differences between years was probably the different availability of prey in these two years, affecting breeding success and post-fledging survivorship of the Tengmalm's owls.

Allosuckling is a situation when a female nurses a non-filial offspring. It was described in various ungulate species; however for camels this is the first description of this behaviour. The aim of the study was to assess the occurrence of allosuckling in captive camels (Camelus bactrianus) and to test whether it can be explained as a ‘milk-theft’ (opportunistic behaviour of calves) or alternatively as an altruistic behaviour of females. During 2005 and 2007, nine camel females and ten calves in four zoological gardens in the Czech Republic were observed. In total, 373 sucking bouts were recorded, from which 32 were non-filial (the calf sucked from the non-maternal female). Allosuckling regularly appeared in captive camel herds. As predicted for the milk-theft explanation, the non-filial calves sucked more often in the lateral position and even did not suck in the antiparallel position at all. The non-filial calves preferably joined the filial calf when sucking but in five cases (15.6% of non-filial sucking bouts) the calves sucked from non-maternal dam without the presence of filial calf. We then expected the differences in terminations of sucking bouts by females but did not find any difference in sucking terminations for filial and non-filial calves. As the calves were getting older, the incidence of allosucking increased. This was probably because skills of the calf to outwit the non-maternal dam increased and/or the older calves might be more motivated for allosucking due to the weaning process. Finally, duration of a sucking bout was shorter with non-filial than filial calves. The results of the study support the hypothesis of ‘milk theft’, being mostly performed by calves behaving as opportunistic parasites, but we cannot reject certain level of altruism from the allonursing females or their increased degree of tolerance to non-filial calves.

Mesenchymal stem cells positive to surface antigen STRO-1 were isolated from regenerating antlers of red deer (Cervus elaphus) and fallow deer (Dama dama) using a magnetic-activated cell sorting (MACS) method. In this study we analysed factors potentially affecting the number of STRO-1+ cells in the cell cultures. With regard to the STRO-1 antigen, we evaluated data from 188 MACS separation procedures of cell cultures cultivated in Dulbecco’s Modified Eagle Medium and 10% fetal calf serum of four fallow deer males (130 procedures) and four red deer males (58 procedures). The analysed factors were the sampling site of the antler or the pedicle, cell passage and type of the cell culture (mixed or STRO-1 negative cell cultures). The percentage of obtained STRO-1+ cells varied greatly from 0.4 to 38.9% for fallow deer and from 1.8 to 16.5% for red deer. We have not found any significant influence of the sampling site. The passage and the type of culture were significant factors for both fallow and red deer cells. The highest numbers of STRO-1+ cells were obtained from the second passage from both fallow and red deer cell cultures (24.6 and 5.5%, respectively). Our experiment revealed that we can maximise the number of STRO-1+ cells in the cultures by manipulating the cultivation factors.

Lactation is the most energy demanding part of parental care in mammals, so parent-offspring conflict arises over milk provided by the mother. In some species females commonly become pregnant shortly after parturition of previous young. This further intensifies mother-offspring conflict due to concurrent pregnancy and lactation. In equids it has been well established that pregnant females wean their foals earlier than non-pregnant ones. Intensified mother-offspring conflict was presumed to associate with pregnancy also during the period of intensive lactation, i.e., before the weaning process starts. We investigated the effect of pregnancy on suckling behaviour characteristics as indicators of mother-offspring conflict in domestic horses. Contrary to expectation, here we provide evidence of a decreased mother-offspring conflict related to pregnancy in lactating females during first two trimesters of pregnancy. Pregnant mares provided longer suckling bouts and did not reject or terminate suckling of their foals more often than non-pregnant mares. Our results suggest that pregnant mares cope with parallel investment into a nursed foal and a foetus through enhancing nursing behaviour in early stages of pregnancy before the initially low requirements of the foetus increase. They compensate their suckling foal with the perspective of its early weaning due to ongoing pregnancy.

Earlier studies have shown variation among experimental attempts to establish whether human monozygotic twins that are genetically identical also have identical individual scents. In none of the cases were the dogs able to distinguish all the individual scents of monozygotic twins living in the same environment if the scents were presented to them separately. Ten specially trained police German Shepherd dogs of three Czech Republic Police Regional Headquarters were used for scent identification in our study. The dogs were supposed to match scents of two monozygotic pairs (5 and 7 years old) and two dizygotic twin pairs (8 and 13 years old). Scents were collected on cotton squares stored in glass jars. Dog handlers were blind to the experiment details. In each trial (line-up), one scent was used as a starting scent and the dog was then sent to determine if any of the 7 presented glass jars contained a matching scent. Scents of children of similar ages were used as distractors. In the matching procedure, the dogs matched correctly the scent of one twin with the other, as well as two scents collected from every single identical and non-identical twin to prove their efficacy and likewise, the presence of the matching twin scent in any given glass jar. All dogs in all trials distinguished correctly the scents of identical as well as non-identical twins. All dogs similarly matched positively two scents collected from the same individuals. Our findings indicated that specially trained German Shepherd dogs are able to distinguish individual scents of identical twins despite the fact that they live in the same environment, eat the same food and even if the scents are not presented to them simultaneously.

A method for the prevention of dark-cutting in beef, based on recognition of social relationships within groups of bulls, was tested on 2234 bulls slaughtered under commercial conditions. When the influence of time between loading the animals and slaughter was eliminated statistically, the bulls of the socially stablized group showed the lowest pH24 values, whereas those of the socially unstable group showed the highest ones. When the type of social group was eliminated statistically, the earlier slaughtered animals had lower pH24 values than those slaughtered later. When the two major factors were integrated, there was no statistically significant difference in the pH24 values in bulls of the socially stabilized group whether they were slaughtered immediately after transport or during the following day. In contrast, in bulls from the socially unstable group, the pH24 values increased substantially after overnight lairage at the abattoir. In conclusion, for longer transportion, bulls from loose housing with stable social relationships should be used. It is necessary to keep the same social groups from loading to slaughter, strictly avoiding any mixing of strange bulls. Bulls from tethered stalls should be transported and slaughtered within as short a time after regrouping as possible.

Close correlations between social dominance and levels of some hormones modulated mainly by agonistic behavior have been reported in mammals. The hormone changes which accompany agonistic interactions appear to be more dramatic and longer lasting than those associated, for example, with sexual interactions (Harding 1981). Clearly, dominant animals generally have lower pituitary/adrenocortical activities than submissive animals living with them. Thus, the dominant -+position usually based on aggressive behavior often tends to be related to elevated androgen level, while subordinate status seems to be associated with lower androgen secretion and increasing levels of glucocorticoids (Brain 1980; Leshner 1980). Increased chronic ACTH/glucocorticoid production in subordinate animals suppresses androgens (Brain 1980). In Cervidae the evidence for these relationships has been obtained in white-tailed deer (Bubenik, A. & Bubenik, G. 1976b; Forand et al. 1985), red deer (Short 1979), and reindeer (Stokkan et al. 1980).

An apparatus consisting of 2 silver ring electrodes attached to a plastic rod and connected to a transistor indicator was used to measure electrical impedance changes in the vagina of rats. A statistically significant increase in electrical impedance occurred at proestrus. By determining when this peak occurs, the optimal time for pairing can be established. In paired animals the absence of the peak provides a reliable means of diagnosing pregnancy.

A five-year observation of social interactions and the antler cycle of the stag was performed in the “white” red deer population in the Žehusice game reserve, Czechoslovakia. The results indicate that the antler casting time of individual stags was dependent primarily on social status and that the influence of age was of secondary importance. The more dominant the stag, the earlier antler casting occurred. The stags of higher social status also tended to shed velvet earlier, although this relationship was not significant. The hormonal regulation of the antler cycle relating to social hierarchy is discussed.

A method for determining the phase of the oestrous cycle by measuring the electrical impedance of the vaginal mucous membrane was examined in the guinea-pig. The apparatus consisted of silver ring electrodes attached to a plastic rod and connected to a transistor indicator. A cyclic increase in impedance was found, and significantly higher values were recorded during the phase of increase (proestrus) than at other times of the cycle. By determining this peak the right time for pairing can be chosen. Conversely, the disappearance of this cyclic culmination in impedance pointed to early pregnancy with a high degree of reliability.

The aim of the study was to test if it is possible to induce complete copulatory behavior in castrated Arctic foxes (Alopex lagopus) of both sexes for the purpose of other experiments. Two groups of castrated, sexually experienced Arctic foxes, four pairs in Experiment 1 (a pilot study) and eight pairs in Experiment 2, were treated with different regimes of hormone (estrogens and progesterone in females, testosterone in males). The animals were than tested for copulatory behavior. Nine out of 12 castrated bitches and 10 out of 12 castrated males displayed copulatory behavior during the season of reproductive quiescence for intact Arctic foxes. All the treatments induced complete copulatory behavior (i.e., copulation leading to locking) at least in some animals of both sexes. Examination of results for individual animals suggested that copulatory performance was influenced by preference for specific partners. Also the occurrence of copulation in an early test facilitated its reoccurrence on a later test in the same day with a different partner.