Baobab (Adansonia digitata L.) density,size-class distribution and population trends between four land-use types in northern Venda,South Africa     

Sarah M. Venter  E.T.F. Witkowski 《Forest Ecology and Management》2010

Baobabs are important to people's livelihoods as a source of food, fibre and medicine. Baobab products are increasingly being commercialised and exported around the world, and pressure on the resource is growing (Sidibe and Williams, 2002). This paper examines baobab population structure and trends in northern Venda, South Africa.  相似文献   

Implications of elevated carbon dioxide on the susceptibility of the globally invasive weed,Parthenium hysterophorus,to glyphosate herbicide     

Blair W Cowie  Nic Venter  Ed TF Witkowski  Marcus J Byrne 《Pest management science》2020,76(7):2324-2332

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Multi-atom resonant photoemission: A method for determining near-neighbor atomic identities and bonding     

A Kay  E Arenholz  S Mun  Garcia de Abajo FJ  CS Fadley  R Denecke  Z Hussain  Van Hove MA 《Science (New York, N.Y.)》1998,281(5377):679-683

Measurements and theoretical calculations are reported for an interatomic multi-atom resonant photoemission (MARPE) effect that permits direct determination of near-neighbor atomic identities (atomic numbers). MARPE occurs when the photon energy is tuned to a core-level absorption edge of an atom neighboring the emitting atom, with the emitting level having a lower binding energy than the resonant level. Large peak-intensity enhancements of 33 to 105 percent and energy-integrated effects of 11 to 29 percent were seen in three metal oxides. MARPE should also be sensitive to bond distance, bonding type, and magnetic order, and be observable via the secondary processes of x-ray fluorescence and Auger decay.  相似文献   

A comparative study of the anatomy of the omasum in domesticated ruminants     

CS McSWEENEY 《Australian veterinary journal》1988,65(7):205-207

The structure of the omasum was compared in 10 water buffalo (Bubalus bubalis), 10 Shorthorn cattle (Bos indicus), 9 Merino sheep (Ovis aries) and 10 cross-bred goats (Capra hircus), and the functional significance of the differences is discussed. The weight of the omasum and area of the internal laminae appeared to be smaller in Brahman cattle than the buffalo and British cattle. When compared in relation to body weight, the omasums of caprid animals were smaller than those of bovids, by a factor of 0.33-0.67 but the omasums of goats were appreciably larger than sheep. The number of laminae ranged from 33 to 35 for the sheep and goats compared with 122 to 169 for the buffalo and cattle. It is suggested that the marked difference in structure of the omasum between the small and large ruminants may influence the food intake of these animals through the effects of this gut compartment on absorption of nutrients and passage of digesta.  相似文献   

The characteristics of a variant strain of Brucella melitensis Rev 1     

P M Pieterson  B Gummow  S Pefanis  C G Venter  S Herr 《The Onderstepoort journal of veterinary research》1988,55(1):15-17

Circumstantial evidence is presented for the occurrence of a variant of a vaccine strain of B. melitensis Rev 1, designated "FSA" (foreign South African). FSA resembles Rev 1 in its reactions to penicillin and streptomycin but reacts closer to a field strain of B. melitensis as regards dye (thionine and basic fuchsin) sensitivity and colony size. Although colonies of Rev 1 were consistently smaller than other B. melitensis strains, their size was 0,75 mm as opposed to the 1-2 mm reported in the literature, while B. melitensis 16M colonies were 1,25-1,5 mm as opposed to the 3-4 mm previously reported. Rev 1 was found to be urease positive, unless a test of low sensitivity was applied.  相似文献   

Evaluation and selection of taro [Colocasia esculentra (L.) Schott] accessions under dryland conditions in South Africa     

Abe Shegro Gerrano  Willem Sternberg Jansen Van Rensburg  Patrick Olusanmi Adebola  Pepukai Manjeru  Michael Wolday Bairu  Sonja Louise Venter 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2019,69(3):219-227

Taro [Colocasia esculenta (L.) Schott] is an important underutilised staple food crop in South Africa, with a lot of potential to address food insecurity among poor rural households. Development of high yielding stable taro cultivars is one of the most important goals of plant breeders. Twenty-nine taro accessions collected from major taro producing regions of the country were evaluated for growth performance, yield potential and stability under dryland conditions at two sites (Umbumbulu and Roodeplaat) in 2013, 2014 and 2015 cropping seasons. The experiment was laid in a randomised complete block design replicated three times. Growth and yield traits were measured. Analysis of variance and correlation analysis was done on all measured traits. The genotype by environment interaction was analysed using additive main effects and multiplicative interaction (AMMI). As a result, significant variation was observed for most of the traits except number of leaves and leaf width as well as number of suckers, while all the traits showed significant variation for location by year interaction. Number of corms showed significant variation for location by year by genotype interaction among all the traits evaluated. Genotype effect was highly significant (p?<?.01) on plant height, corm length, number of corms and significant (p?<?.05) on yield. The significant difference between genotypes for these traits proves that there was a genetic variability and there is a scope for selection. The correlation study also reveals that majority of the characters were positively correlated with each other. Total yield was positively and highly significantly (p?<?.01) correlated with all the measured traits. AMMI was effective in identifying stable genotypes. The top ranking cultivars per environment may be considered for cultivation under the specific environment, the stable cultivars may be considered for cultivation across all the taro growing regions.  相似文献   

Ixodid ticks on domestic dogs in the Northern Cape Province of South Africa and in Namibia     

Matthee S  Lovely C  Gaugler A  Beeker R  Venter HR  Horak IG 《Journal of the South African Veterinary Association》2010,81(2):126-128

The objective of this study was to determine the species composition of ixodid ticks infesting domestic dogs in the northwestern region of the Northern Cape Province of South Africa and in Namibia. Ticks were collected from February 2008 to January 2009 from dogs presented for a variety of reasons at a veterinary clinic in the Northern Cape Province and at 3 clinics in Namibia. The ticks collected at each place were pooled separately for each month at each locality. Eleven ixodid tick species were collected from dogs in the Northern Cape Province and new locality records for Haemaphysalis colesbergensis and Ixodes rubicundus, new locality and host records for Hyalomma glabrum, and a new host record for Rhipicephalus neumanni are reported. Six tick species were collected from dogs at the 3 clinics in Namibia. The most numerous species on dogs in both countries was R. sanguineus. The present results increase the total number of ixodid tick species collected from dogs in South Africa from 25 to 28.  相似文献   

Identification of lactoferrin and glutamate receptor‐interacting protein 1 in bovine cervical mucus: A putative marker for oestrous detection          下载免费PDF全文

WY Lee  MH Park  KW Kim  H Song  KB Kim  CS Lee  NK Kim  JK Park  BC Yang  KB Oh  GS Im  HJ Chung 《Reproduction in domestic animals》2017,52(1):16-23

Accurate detection of oestrus is important for artificial insemination. The aim of this study was to identify oestrous‐specific bovine cervical mucus proteins that could be used to determine the optimal time for artificial insemination. Non‐oestrous and controlled internal drug release (CIDR)‐induced oestrous‐stage mucus proteins were purified and subjected to surface‐enhanced laser desorption/ionization time‐of‐flight mass spectrometry, sodium dodecyl sulphate polyacrylamide gel electrophoresis and MALDI‐TOF/TOF. Among differentially expressed proteins, lactoferrin (LF) and glutamate receptor‐interacting protein 1 (GRIP1) showed a twofold increase during the CIDR‐induced oestrous stage compared to the levels in non‐oestrous stage in bovine cervical mucus. The RT‐PCR, Western blotting and immunohistochemistry results showed that LF and GRIP1 expression was significantly increased during the oestrous stage in the uterus. This study demonstrated that bovine LF and GRIP1 exist during the oestrous stage, but not during the non‐oestrous stage, suggesting that cervical mucus LF and GRIP1 are useful oestrous detection markers in cattle.  相似文献   

Evaluation of BAM (butorphanol–azaperone–medetomidine) in captive African lion (Panthera leo) immobilization     

Aleksandr Semjonov  Vladimir Andrianov  Jacobus P. Raath  Toomas Orro  Derik Venter  Liesel Laubscher  Silke Pfitzer 《Veterinary anaesthesia and analgesia》2017,44(4):883-889

Objective

The combination of butorphanol, azaperone and medetomidine (BAM) with subsequent antagonism by naltrexone–yohimbine or naltrexone–atipamezole was evaluated for reversible immobilization of captive African lions (Panthea leo).

Study design

Prospective, clinical trial.

Animals

Twenty lions, 11 males and nine females, weighing 38–284 kg were immobilized in South Africa.

Methods

The BAM volume dose rate administered was 0.005–0.008 mL kg^?1 (0.6 mL 100 kg^?1). Physiologic variables were recorded every 5 minutes. Four arterial blood samples were collected from all animals at 20, 30, 40 and 50 minutes after immobilization for analysis of blood-gases and acid-base status.

Results

The actual doses administered were as follows: butorphanol, 0.18 ± 0.03 mg kg^?1; azaperone, 0.07 ± 0.01 mg kg^?1; and medetomidine, 0.07 ± 0.01 mg kg^?1. The inductions were calm and smooth, and induction time ranged from 4 to 10 minutes (7 ± 2 minutes). The amount of time needed to work with each lion was 70 minutes, and no additional drug doses were needed. Heart rate (40 ± 8 beats minute^?1) and respiratory frequency (15 ± 4 breaths minute^?1) were stable throughout immobilization. The mean arterial blood pressure of all animals was stable but elevated (142 ± 16 mmHg). The rectal temperature slightly increased over time but remained within acceptable range. The recovery time was significantly shorter when using naltrexone and atipamezole (9 ± 1 minutes) compared to using naltrexone and yohimbine (22 ± 7 minutes).

Conclusion and clinical relevance

The BAM combination proved to be reliable for general veterinary anaesthesia in lions. During anaesthesia, minor veterinary procedures such a blood collection, intubation, vaccination and collaring could safely be performed with no additional dosing required.  相似文献   

Factors Affecting the Readiness and Preparation of Replacement Heifers in Tropical Breeding Environments     

M Maquivar  CS Galina 《Reproduction in domestic animals》2010,45(5):937-942

The future of beef cattle production in tropical regions is uncertain because of land tenure concerns, threatening the survival of extensive management programmes in these areas of the world. The need to intensify production systems will inevitably lead to changes in the management of replacement animals in existing herds. The present review underlines the main constraints, which in the past could be resolved by the sheer numbers of animals present in beef cattle operations, with replacements reliant only on finding enough heifers to substitute the adult females destined for culling. This scenario is rapidly changing as beef cattle units in tropical regions subdivide to share out the land between as many farmers as possible. Consequently, issues such as the efforts needed to manage the pregnant cow, particularly her nutritional status and its effect on the new‐born calf, the future replacement heifer growing in the presence of the dam, weaning management and procedures required before a heifer can be introduced into a breeding programme, need to be adequately and efficiently addressed by farmers in tropical regions.  相似文献