Karolína Brandlová

Camel Calves as Opportunistic Milk Thefts? The First Description of Allosuckling in Domestic Bactrian Camel (Camelus bactrianus)

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.

Stealing milk by young and reciprocal mothers: high incidence of allonursing in giraffes, Giraffa camelopardalis

Allonursing, the nursing of nonfilial offspring, has been reported in a number of mammalian species; however, very few studies have investigated more than three hypotheses. The aim of our study was to investigate seven hypotheses explaining allonursing in captive giraffes. During 2007–2011, we observed 24 females and 37 calves in four zoological gardens in the Czech Republic, recording 2514 suckling events. We found that 83% of the females allonursed a nonfilial calf and 86.5% of calves allosuckled from a nonmaternal female; thus giraffes represent one of the highest occurrences of allonursing among nondomesticated mammals. The nonfilial calves more often allosuckled together with the filial ones than alone and tried to adopt positions where they may be harder to recognize, providing evidence for the milk theft hypothesis. In addition, the probability that a calf successfully allosuckled at least once from any female was higher when its mother allonursed successfully at least once than when she rejected calves. However, we found no evidence for the same rate of allonursing between reciprocal dyads of females and calves. Thus, we suggest that allonursing in giraffes is caused by offspring trying to steal milk and that females may tolerate this behaviour if reciprocal, in line with recent findings about giraffe sociality.

The First Description of Dominance Hierarchy in Captive Giraffe: Not Loose and Egalitarian, but Clear and Linear

Wild giraffes live in extensive groups in the fission fusion system, maintaining long social distances and loose social bonds. Within these groups, resources are widely distributed, agonistic encounters are scarce and the dominance hierarchy was reported in males only, while never deeply analysed. In captivity, the possibility to maintain inter-individual distances is limited and part of the resources is not evenly distributed. Consequently, we suggest that agonistic encounters should be more frequent, leading to the establishment of the dominance hierarchy. Based on the differences in resource-holding potential, we suggested that the rank of an individual would be affected by age and sex. Based on hypotheses of prior ownership, we tested whether rank was positively affected by the time spent in a herd and whether it was stable in adult females, which were present long-term in the same herd. We originally monitored four herds of Rothschild giraffes (Giraffa camelopardalis rothschildii) in Dvůr Králové zoo (n = 8), Liberec zoo (n = 6), and two herds in Prague zoo: Prague 1 (n = 8) and Prague 2 (n = 9). The Prague 1 and Prague 2 herds were then combined and the resulting fifth herd was observed over three consecutive years (2009, 2010, and 2011) (n = 14, 13, and 14, respectively). We revealed a significantly linear hierarchy in Dvůr Králové, Prague 2 and in the combined herd in Prague. Rank was significantly affected by age in all herds; older individuals dominated the younger ones. In females, rank was positively affected by the time spent in the herd and adult females in Prague maintained their rank during three consecutive years. This study represents the first analysis of the dominance hierarchy in the captive giraffe, and discusses the behavioural flexibility of the social structure in response to monopolisable resources in a captive environment.

Social Preferences of Translocated Giraffes (Giraffa Camelopardalis Giraffa) in Senegal: Evidence for Friendship Among Females?

Abstract Giraffe social behaviour and relationships are currently in the period of scientific renaissance, changing the former ideas of nonexisting social bonds into understanding of complex social structures of giraffe herds. Different giraffe subspecies have been studied in the wild and only one was subject of detailed study in captivity. Our study focused on the neglected Cape giraffe (Giraffa camelopardalis giraffa). We investigated the social preferences of 28 introduced giraffes in semi-captivity in Bandia reserve, Senegal. Our aim was to assess the group size of Cape giraffes outside their native range and describe their social relationships. Mean group size in Bandia was 7.22 ± 4.06 (range 2-17). The dyads were classified according to strength of relationship (weak, medium, strong) using the association index. We reported weak and medium relationships in all types of dyads except female-juvenile. The strongest bond was found in mother-calf dyads. Three of 21 possible female dyads also demonstrated strong relationships. Those three dyads included six of seven adult females, which we labelled as friends. Females associated more frequently with calves of their friends then with calves of non-friend females. The strength of the relationship between calves depended on the strength of relationship between their mothers. We concluded that Cape giraffes in new environment have shown similar group size and nonrandom preference for conspecifics as shown in wild and captive studies. The research was supported by CIGA 20135010, CIGA 2134217, IGA FTZ 20135123, ESF/MŠMT CZ.1.07/2.3.00/30.0040.

Saliva Crystallization in Cattle: New Possibility for Early Pregnancy Diagnosis?

Abstract Saliva sampling is a non-invasive, simple and low-cost procedure. The aim of this study was to confirm the presence and changes of saliva crystallization in domestic cattle during synchronized oestrous cycle and early pregnancy. We verified saliva crystallization as a method for early pregnancy diagnosis. Eight Holstein cows were included into the research. The samples were collected daily from 16th day before to 34th day after artificial insemination (in total 51 days). We observed the following types of crystallization: none, dotted, branch-like, fir-like, fern-like and combinations of them and an atypical pattern. We confirmed the presence of saliva crystallization in cattle and its changes during oestrus synchronization process, insemination and post-insemination periods. We found significant differences in pregnant and non-pregnant animals between 20th and 29th day after insemination. We concluded that pregnancy diagnosis by saliva crystallization might be possible but the practical application of this method is currently unfeasible.

Environmental Education Supports Conservation Action by Increasing the Immediate and Long-Term Environmental Knowledge of Children in West Africa.

ABSTRACT Local communities play a key role in the sustainability of any conservation program. We evaluated the impact of an environmental education program for school children in the surroundings of the Delta du Saloum Biosphere reserve (Senegal) dedicated to the conservation of African charismatic fauna with the critically endangered Western Derby eland as a conservation flagship. Questionnaires evaluating knowledge and attitudes were filled in by children before and after the program in 2008 and 2009. We found a significant increase in knowledge that carries the potential to support conservation activities of protected area management. This knowledge alone is, however, not enough to change behavior and attitudes, proving the need to approach the problem in context of a complex, targeted awareness campaign.

Giraffe nursing behaviour reflects environmental conditions

Nursing behaviour is one component of mammalian life history strategy that demonstrates context-dependent flexibility within species. Wild giraffes live in groups and feed themselves over large area. In the zoo, giraffes are kept in enclosures with abundant food resources. We aimed to analyse whether the nursing behaviour of giraffes differs between the zoo and nature reserve and discuss which factor (food intake, presence of predators, population density) can explain the difference. We observed seven and four female–calf pairs in the Bandia reserve, Senegal, and in Prague Zoo, Czech Republic, respectively. Nursing bouts were less frequent and longer and calves were less successful in nursing solicitations in the reserve, as females there seemed to be more selective for nursing times and locations, likely due to presence of predators and differences in food intake. Allonursing occurred more frequently in the zoo which can be attributed to higher population density in captive conditions.

The weight of Rothschild giraffe-Is it really well known?

Despite being regularly bred in zoos, giraffes remain a challenge, especially in terms of feeding. Assessment of factors influencing growth and weight changes during ontogeny, as well as analysis of weight fluctuations in adult individuals, may become a critical point in captive diet evaluation. Knowledge about weight is a crucial husbandry tool; however, such data are rarely acquired. Using a unique dataset from regularly weighed Rothschild giraffes (Giraffa camelopardalis rothschildi) from Prague zoo, we determined the growth functions of male and female giraffes and calculated weight gains during giraffe ontogeny. The mean weights of adult males and females were 1307 ± 52 and 835 ± 45 kg, respectively confirming the large overall dimensions of G. c. rothschildi in comparison with other giraffe subspecies. As the giraffe is a polygynous species showing considerable sexual dimorphism, we expected male calves to have larger first weights and faster growth during the most intensive period of maternal care. Growth rates and daily weight gains were higher in males than in females during the whole postnatal period. Males grew faster and longer than females. However, differences in weight between males and females appeared as late as after 1 year of age. The weight of adult males and non-pregnant adult females fluctuated significantly across seasons, being the highest during the autumn and winter months, respectively which may reflect the different effects of sexual activity and feeding ratios in males and females. Zoo Biol. 35:423-431, 2016.

APPLICATION OF NONINVASIVE PREGNANCY DIAGNOSIS IN BACTRIAN CAMELS (CAMELUS BACTRIANUS) USING CUBONI REACTION AND BARIUM CHLORIDE TEST.

Pregnancy diagnoses in half-tamed animals are often very complicated. This study aimed to examine the alternative noninvasive and cheap methods of pregnancy diagnosis from urine in domestic Bactrian camels (Camelus bactrianus). Urine from 14 female camels kept in four European zoologic gardens was collected and tested by two chemical tests--Cuboni reaction and barium chloride test. The Cuboni reaction was significantly (P<0.01) affected by the pregnancy status of female camels. The total accuracy of the Cuboni reaction was 70.5% but it increased significantly (P<0.05) in the time leading up to parturition. The accuracy was 100% in the 3rd third of pregnancy. Urine of nonpregnant females did not react with a solution of barium chloride while, contrary to other studies, white precipitates formed mostly (80 to 100%) in urine of pregnant females. This study concluded that the Cuboni reaction is applicable for pregnancy diagnosis in camels.

Feeding rank in the Derby eland: lessons for management

Transfers to new breeding herds and supplementary feeding are crucial management steps for small populations of ungulates. However, the successful realisation of those steps is strongly dependent on social interactions among individuals. Agonistic encounters connected with feeding determine the quality and quantity of the food accessed, and therefore directly influence food intake. We analysed the dominance relationships of mixed herds of critically endangered Western Derby eland with regard to access to supplementary food in the Bandia reserve, Senegal. We tested the influence of age and sex on feeding rank, the linearity and stability of hierarchies and the relationship between the position of an offspring in the hierarchy and the position of its mother. A linear hierarchy existed in all herds. Sex influenced the rank only in interaction with age. Feeding rank was significantly related to age in growing animals; in adults the effect of age was weaker. While body mass is correlated with age during the growth period and not after reaching adulthood, we concluded that the position in the hierarchy was related to the actual condition, reflecting the resource holding potential of individuals. The dominance index of a growing offspring depended on the index of its mother, but hierarchies of adult individuals were not stable. High-ranking individuals in good condition limited access to supplementary feeding to their lower-ranking herdmates. Effective supplementary feeding should therefore be provided in excess amounts to enable younger and weaker individuals in need to benefit from it, despite their lower positions in the hierarchy.