Suckling behavior of eland antelopes (Taurotragus spp.) under semi-captive and farm conditions

Mother–offspring interactions soon after parturition play a key role in the survival of mammals. We investigated the suckling behavior of semi-captive Western Derby eland (Taurotragus derbianus derbianus) in a 60-ha enclosure covered by dense savanna vegetation in Senegal and farmed Common eland (T. oryx) on an open 2-ha pasture in the Czech Republic. We hypothesized that the basic pattern of suckling bout duration and mother–offspring interactions would be similar between species, but would vary in response to the environmental conditions and breeding system. During three calving periods, we observed the suckling of 27 and 23 calves of Derby and Common elands, respectively, between the ages of 1–5 months, and the interactions between mother and calf before and during suckling. Suckling bout duration increased with the age of the calves for both elands. However, in Derby elands we recorded longer suckling bouts in male than female calves and shorter suckling bouts in primiparous mothers than multiparous ones; no differences were found in farmed Common elands. The animals’ active approach to mother–offspring contact, for example naso–anal contact, and initiation and termination of suckling, resulted in longer suckling bouts in Derby elands. The results suggest that Derby elands that range over a large enclosure with dense vegetation cover adjust their maternal behavior in compliance with potential predator risk, facing a trade-off between nursing and vigilant behavior in the wild. The suckling behavior of farmed elands, on the other hand, reflects the conditions of captivity without predators and with the small available area enabling permanent visual contact of animals.     

Ultrasonographic-guided retrieval and in vitro maturation of eland (Taurotragus oryx) and bongo (Tragelaphus eurycerus isaaci) antelope oocytes

The limited availability of gametes is a major factor hindering the development and application of assisted reproductive technologies (ART) in large non-domestic ungulates. This is partly due to the small number of captive animals and handling difficulties associated with procedures for gamete recovery. In the present study, results are reported of multi-year studies on ovarian stimulation and oocyte retrieval by ultrasonographic-guided transvaginal follicular aspiration and subsequent in vitro maturation (IVM) in eland and bongo antelopes. All procedures were conducted on sedated females handled in a hydraulic chute without inducing general anesthesia. Five estrous synchronization/ovarian stimulation protocols were evaluated and data are presented on 73 and 15 procedures in eland and bongo, respectively. Repeating procedures (< or =once/month) on the same female did not affect ovarian response or number oocytes recovered in either species. Eland females, but not the ovarian stimulation treatment, affected ovarian response. Ovarian stimulation treatment affected oocyte recovery rate in eland, but not in bongo. In both species, ovarian hormone stimulation treatment affected the distribution of follicles by size and the status of expansion of the cumulus cell investment of oocytes, but not the frequency of metaphase II oocytes during IVM. The timing of extrusion of the first polar body during IVM was more synchronous in bongo than in eland oocytes. It is concluded that Transvaginal oocyte retrieval (TVOR) can be safely and repeatedly applied in gonadotropin-treated eland and bongo females to recover oocytes that can mature in vitro. The methods described for the present study can be adapted to improve the availability of non-domestic ungulate oocytes for basic and applied studies.     

The Palearctic blackfly Simulium equinum (Diptera: Simuliidae) as a biting pest of captive nyala antelopes (Tragelaphus angasii)

Blackflies (Diptera: Simuliidae) are cosmopolitan nuisance pests of great economic importance as well as vectors of many pathogens. After reports of massive blackfly biting of captive nyala antelopes in the Vienna Zoo, Austria, this study aimed to identify the species causing multiple skin lesions on the antelope hosts. The Palearctic species Simulium equinum, belonging to the medically and veterinary important Wilhelmia subgenus, was identified as the most likely causative agent. Barcoding and maximum likelihood analysis supported morphological species identification and highlighted the complex phylogeny of the subgenus Wilhelmia. Our study gives first evidence of the multi-host feeding blackfly S. equinum in the Vienna Zoo, thereby raising the question whether other hosts could also be bitten on a regular basis. The preliminary results urge for further analysis of blackfly breeding sites as well as the clarification of the host spectrum to assess the medical and veterinary importance of blackflies in the Zoo.     

Arachidonic acid metabolites, hydrogen peroxide, and EDHF in cerebral arteries

We tested the hypotheses that EDHF in rat middle cerebral arteries (MCAs) involves 1) metabolism of arachidonic acid through the epoxygenase pathway, 2) metabolism of arachidonic acid through the lipoxygenase pathway, or 3) reactive oxygen species. EDHF-mediated dilations were elicited in isolated and pressurized rat MCAs by activation of endothelial P2Y(2) receptors with either UTP or ATP. All studies were conducted after the inhibition of nitric oxide synthase and cyclooxygenase with N(omega)-nitro-l-arginine methyl ester (10 microM) and indomethacin (10 microM), respectively. The inhibition of epoxygenase with miconazole (30 microM) did not alter EDHF dilations to UTP, whereas the structurally different epoxygenase inhibitor N-methylsulfonyl-6-(2-propargyloxyphenyl)hexanoic acid (20 or 40 microM) only modestly inhibited EDHF at the highest concentration of UTP. An antagonist of epoxyeicosatrienoic acids, 14,15-epoxyeicosa-5(Z)-enoic acid, had no effect on EDHF dilations to UTP. Chronic inhibition of epoxygenase in the rat with 1-aminobenzotriazol (50 mg/kg twice daily for 5 days) did not alter EDHF dilations. The inhibition of the lipoxygenase pathway with either 10 microM baicalein or 10 microM nordihydroguaiaretic acid produced no major inhibitory effects on EDHF dilations. The combination of superoxide dismutase (200 U/ml) and catalase (140 U/ml) had no effect on EDHF dilations. Neither tiron (10 mM), a cell-permeable scavenger of reactive oxygen species, nor deferoxamine (1 or 10 mM), an iron chelator that blocks the formation of hydroxyl radicals, altered EDHF dilations in rat MCAs. We conclude that EDHF dilations in the rat MCA do not involve the epoxygenase pathway, lipoxygenase pathway, or reactive oxygen species including H(2)O(2).     

Deoxyribonucleic acid base composition and taxonomy of Moniliella and allied genera

DNA base compositions of representative (type) strains of Moniliella, Trichosporonoides and Hyalodendron were determined. Within Trichosporonoides over 16% variance was found. Most species separated well, but M. suaveolens showed considerable heterogeneity. The standard 2% G+C differences for species distinction is probably not applicable to these yeasts. The new combination M. pollinis is proposed for M. tomentosa var. pollinis on the basis of slight ecological, morphological and physiological differences, supported by a marked difference in % G+C.     

The microcirculation of cerebral arteries: a morphologic and morphometric examination of the major canine cerebral arteries

A morphologic and morphometric examination of the major cerebral blood vessels in the dog was carried out to determine whether there were vasa vasorum in these arteries and what features might be associated with them. True vasa vasorum confined to the media were not seen in any of the vessels examined. Microvessels confined to the adventitia, however, were found in the internal carotid and vertebral arteries but not in the basilar, middle cerebral, or anterior spinal arteries. Animal size, vessel size as determined by adventitial and medial area, and the number of smooth muscle cell lamellae were not associated with the presence of these adventitial vessels; they occurred only in arteries with both an intra- and extradural portion. It therefore appears that most canine cerebral arteries do not have vasa vasorum.     

Calcium and phosphorus in aged human cerebral arteries

To elucidate the compositional changes of the cerebral arteries with aging, the authors investigated age-related changes of the calcium and phosphorus contents in the cerebral arteries by inductively coupled plasma-atomic emission spectrometry. The subjects consisted of 11 men and 5 women, ranging in age from 52 to 96 yr. The anterior, middle, and posterior cerebral arteries derived from the same subjects were used in the present study. It was found that there were no significant relationships between age and calcium or phosphorus content in the anterior, middle, and posterior cerebral arteries, indicating that the accumulation of calcium and phosphorus scarcely occurred in the anterior, middle, and posterior cerebral arteries with aging. It was examined whether there were relationships in the calcium and phosphorus contents among the anterior, middle, and posterior cerebral arteries. It was found that there was a significant relationship in both the contents of calcium and phosphorus between the middle and posterior cerebral arteries, but not between the anterior and middle cerebral arteries nor between the anterior and posterior cerebral arteries.     

Placental morphology in African antelopes and giraffes

Delivered placentas from nineteen antelopes and five giraffes and placentas from five antelopes dead during parturition and eight antelopes dead during advanced pregnancy were morphologically examined. Placental length and weight, arrangement, number and size of cotyledons, and other features were recorded wherever the conditions of placentas permitted.

Cotyledon rows corresponded to the caruncle rows on uterine walls. The number of rows was usually four, although in Hippotraginae it was six to eight and in Reduncinae it was two. Numbers of cotyledons matched or were lower than total numbers of caruncles in the uteri of most species. In antelopes with uterus duplex [Hippotraginae and wildebeests (Alcelaphinae)] and in other members of the Alcelaphinae subfamily, the placenta occupied only one uterine horn and the numbers of cotyledons corresponded to the numbers of caruncles in one uterine horn. Amniotic “manes” and “plaques” were found in some placentas.     

Trifurcations of the middle cerebral arteries

The furcation types of 100 human middle cerebral arteries (MCA) were investigated. Considering the physiological flow characteristics in furcations, a distinct definition for a bifurcation and a trifurcation was found. The common ramification type of the human MCA is the bifurcation. Trifurcations are very rare and we found them only in the proximal parts of the MCA. In 7 of the 100 cases, a trifurcation was found at the main division of the MCA, in 3 cases a secondary trunk trifurcated. Quadro- and pentafurcations according to the hydrodynamic definitions were not observed at all. Only in 1 case did the internal carotid artery trifurcate into the anterior cerebral artery, a superior trunk and an inferior trunk of the MCA.     

Sympathetic control of cerebral arteries: specialization in receptor type, reserve, affinity, and distribution

The sympathetic neuroeffector system in the mammalian cerebral circulation has a number of distinctive features that reflect its specialized role in this vascular bed: 1) there is limited alpha-adrenoceptor-mediated contraction in large vessels that becomes progressively less important with branching; 2) contraction is limited by receptor number; small branches often seem to have no functional alpha adrenoceptors; 3) adrenoceptor affinity for norepinephrine is low and so is sensitivity; and 4) the dominant alpha-adrenoceptor subtype differs in different species and may have unique characteristics in some. There is a mechanism of non-alpha-adrenoceptor-mediated contraction involving low-affinity receptor sites--extraceptors--activated by sympathetic nerves. The pig has a seemingly atypical sympathetic mechanism. On the basis of current information the sympathetic neuroeffector mechanisms of the rabbit seem most clearly related to the human. The size, pattern, and distribution of sympathetic control suggest that the role of the sympathetic nerves is to protect the smaller pial arteries against the consequences of sudden increases in sympathetic adrenal discharge. It is not an important mechanism of controlling cerebral blood flow.     

Adrenergic and cholinergic innervation of rat cerebral arteries

Summary A consecutive demonstration of both aminergic and cholinergic nerves of rat cerebral arteries was carried out on whole mount preparations. For demonstration of aminergic nerves the glyoxylic acid method was used, while for cholinergic nerves Karnovsky's technique was utilized consecutively. This procedure provided a highly sensitive and reproducible demonstration of the two systems on the same specimen. The results obtained were as follows: 1) Aminergic and cholinergic nerves were distributed densely in the proximal portions of the major cerebral arteries examined. They were dense in the arteries of the anterior circulation and sparse in the posterior circulation. Each nerve had two different patterns, i.e. circular and longitudinal. Both circular and longitudinal patterns were observed in the proximal portions of the arteries, while in the distal portions, longitudinal fibres were predominantly present. 2) Superior cervical ganglionectomy produced no change in cholinergic nerve distribution, while it caused decreased density of aminergic nerves on the ipsilateral side on the arteries of the anterior circulation. The contralateral anterior cerebral arteries were partially affected. Bilateral sympathectomies abolished aminergic nerves in all arteries except the vertebral artery.     

Comparison of GNRH3 genes across salmonid genera

Genomic sequences of gonadotropin-releasing hormone genes were amplified and examined for sequence divergence among members of three different genera of the subfamily Salmoninae: rainbow trout (Oncorhynchus mykiss), Atlantic salmon (Salmo salar), and Arctic charr (Salvelinus alpinus). Sequences of GNRH3A and GNRH3B (formerly known as sGnRH1 and sGnRH2) were 97-99% similar in coding regions and 94-98% similar in non-coding regions among genera, but comparisons within species between GNRH3A and GNRH3B were only 90-92% similar in coding regions and 83-89% similar in non-coding regions. Polymorphisms in the parents of mapping families for each species allowed for linkage mapping of the GNRH3B gene in all three species and the GNRH3A gene in rainbow trout. GNRH3B maps to linkage group 6 in rainbow trout, linkage group 16 in Atlantic salmon and linkage group 25 in Arctic charr. GNRH3A mapped to linkage group 30 in rainbow trout.     

Some uterine parameters in antelopes and a giraffe

Uteri of 69 African antelopes and a giraffe were morphologically examined and numbers of caruncles and their rows in each horn were recorded. Antelopes of subfamilies Taurotraginae, Aepycerotinae, Antilopinae, and Alcelaphinae had about 50 to 100 caruncles arranged in four rows in each uterine horn. Hippotraginae had about 100 to 200 caruncles in six to eight rows in each horn, and Reduncinae had about 10 to 20 caruncles in two rows in each uterine horn. The giraffe had about 70 caruncles arranged in four rows in each uterine horn. Uterine caruncles in some antelopes had specific features such as pigmentation of apices, caruncles on stems, and caruncles with honeycomb structure.     

Condition and related mortality of nyala Tragelaphus angasi in Zululand, South Africa

The kidney fat index (KFI) was used to examine the condition of nyala over a 27-m-onth period. From a sample in which both marrow fat and KFI were examined, it was noted that, as has been found in other bovid, kidney fat was mobilized before marrow fat. Seasonal changes in condition were observed and correlated with the rainfall in the previous month. Following periods of less than 50 mm of rain, the larger adult males were in significantly poorer condition than other animals.
The sexual difference in condition is attributed to the differences in body size, where males of asymptotic body mass required 62% more kcal/day than asymptotic mass females. When die-offs occurred during periods of nutritional stress, significantly more old adults died than would be expected. Further, significantly more males died than females.