Metabolic fecal nitrogen and digestibility estimates in the grasscutter (Thryonomys swinderianus)

The metabolic fecal nitrogen and digestibility estimates in the grasscutter were determined using 12 captive-bred adult animals fed with four experimental diets differing primarily in crude protein content using nitrogen balance trial approach. Grasscutters required 343.5 mg N kg^-0.75 d^-1 of nitrogen to meet maintenance requirements, which were met on diets containing 7.4% crude protein. The true digestibility of nitrogen was moderate (52%) but within the range for eutherians. Dry matter intake increased with decreasing dietary nitrogen content, suggesting that animals on nitrogen-deficient diets displayed appreciable compensatory intake. Metabolic fecal nitrogen was 3.5 g N kg^-1 dry matter intake, and endogenous urinary nitrogen was 257.5 mg N kg^-0.75 d^-1. The low value of metabolic fecal nitrogen found for grasscutters affected the dry matter intake required for nitrogen balance, and it may allow grasscutters to exploit nitrogen poor diets.     

Current knowledge and breeding perspectives for the spider plant (<Emphasis Type="Italic">Cleome gynandra</Emphasis> L.): a potential for enhanced breeding of the plant in Africa

Cleome gynandra is one of the most promising African leafy vegetables consumed in most parts of Africa. The crop is a rich source of vitamins A and C and minerals such as calcium, iron, magnesium and protein. The leaves and seeds of spider plant are used in indigenous medicine in several countries. Despite the numerous nutritive benefits and ethnopharmacological uses of the plant, C. gynandra is still underutilized due to lack of awareness and promotion of production technologies and utilization. Available information is limited and short on several relevant and rudimentary components. Hence, this review focuses on the current knowledge on C. gynandra, with regards to its botany, ecology, cultivation systems, utilization, nutraceutical properties as well as the breeding avenues that will contribute to promoting the species, aimed at ensuring food and nutritional security and efficient management of its genetic resources. Breeding programmes aimed at minimizing the bitterness of the leaves so to arouse the interest of consumers, and the mechanisms involved in the responses and adaptation of C. gynandra as a C₄ plant to salinity stress, were also explored.     

Utilization of organic materials in soil aggregates by bacteria and fungi

Cultures of six fungi and two bacteria were added to samples of aggregates in which either ¹⁴C-labelled glucose or starch was thoroughly distributed in macro- and micropores or in control samples where the labelled substrates were added to the preformed aggregates and considered to be mainly in macropores. The release of ¹⁴CO₂ was monitored over a 24-day incubation.In the control samples with substrates mainly in macropores, the bacteria were as active as fungi in releasing ¹⁴CO₂ from both soils. When the substrates were distributed in macro- and micropores in aggregates made from a fine sandy loam, the fungi were more efficient than bacteria in releasing ¹⁴CO₂. This was not the case in a self-mulching clay.The initial flush of ¹⁴CO₂ released during incubation of the amended fine sandy loam was due mainly to fungi, which were followed by a secondary bacterial population. The change in populations occurred simultaneously with a step in the cumulative ¹⁴CO₂ release curve thought to be due to the utilization of all the labelled substrate added, followed by renewed respiration as the secondary population flourished. The results presented fit well with an efficiency of C assimilation by micro-organism in soil of about 60%.     

Articular/epiphyseal osteochondrosis in Thoroughbred foals at 5 months of age: Influences of growth of the foal and prenatal copper supplementation of the dam

AIMS: To determine the influence of copper (Cu) supplementation by injection of mares in late gestation on the frequency and severity of osteochondrosis (OC) lesions in their foals at around 160 days of age. To determine if there was any influence of the concentration of Cu in the liver, growth rate, birthweight, weight at 160 days of age, fatness, sex, or year of birth of the foal on the frequency and severity of OC lesions. To determine the influence of dam's age, and sex and birthweight of the foal on the growth rate from birth to 160 days of age, and weight at 160 days of age.

METHODS: Thirty-three Thoroughbred foals, born in two consecutive years, were weighed every 2 weeks from birth. The dams had been supplemented with parenteral Cu or saline during late gestation, and the supplementation regimens were different in each year. Foals had liver biopsies harvested at birth for determination of Cu concentration. Pasture samples were collected every 4–8 weeks for analysis of concentration of Cu and zinc (Zn). At 160 days of age, articular cartilage of long bones was examined. Gross lesions were counted and scored, then sawn and radiographed, and processed for histopathology. Lesions were given radiographic scores and histopathological scores. Maximum scores for each lesion were combined to give a total OC score for each joint and each foal. The fatness of 20 foals (10 each from Years 1 and 2) at 160 days of age was determined chemically.

RESULTS: Supplementation of dams with Cu had no significant effect on the concentration of Cu in the liver of foals at birth, or on the frequency or severity of lesions in articular cartilage at 160 days of age. The Cu and Zn concentrations of pasture were similar in Years 1 and 2, and were lower than current recommendations. All foals in Year 2, and 9/10 foals in Year 1 had irregularities in cartilage that was confirmed histologically to be indicative of OC. The average number of lesions per foal was 4.7 (SD 1.1) and 5.7 (SD 1.1) in Years 1 and 2, respectively. However, the severity of the lesions was considered mild, and no foals showed any clinical evidence of OC while alive. The number of lesions in the tarsocrural (TC) joint and the TC OC score at 160 days were positively associated with average daily weight gain (ADG) in the previous 4 weeks (p=0.005 and p=0.001, respectively). There was no significant effect of sex, fatness, birth-weight, weight at 160 days of age, or year of birth of the foal on the frequency and severity of OC lesions.

CONCLUSIONS: Many of the lesions classified as OC, using classification systems described by other authors, were likely to be normal variations of the process of endochondral ossification. Despite the high frequency of such lesions, they were considered to be of minor significance and none were clinically evident. The distribution of lesions was not typical, and most probably reflected the subtlety of the lesions. These results support the hypothesis that Cu is an over-emphasised factor in the aetiopathogenesis of OC. The relationship between subtle macroscopic lesions and lesions resulting in clinical signs of disease requires further investigation.     

Predicting the energy and protein requirements of the pregnant grasscutter (Thryonomys swinderianus, Temminck) using the changes in weight and composition of the foetus and associated tissues of pregnancy

Eighteen (18) gravid uteri collected from hunters’ kills during February and March 2008 were used to investigate growth and accretion of energy and protein in the gravid uterus during pregnancy in the grasscutter. Each gravid uterus was separated into foetal, placental, empty uterus and foetal fluids (amniotic and allantoic fluids combined) components. Individual tissues were weighed and analyzed for dry matter (DM), ash, crude protein (CP) and crude fat. Regression equations were fitted to the weights of each component to describe the effects of gestational age. The DM, protein and energy contents of individual uterine tissues, with the exception of the DM of the foetal fluids, increased significantly with advancing gestation age so that the DM of the gravid uterus increased ~20-fold from days 45 to 152 (3.85 v. 76.24 g). However, the average elemental N in the foetus was 8.3 g?N/100 g. Percentage DM did not change with advancing gestation age. Fat content of the foetal grasscutter was 2.79 %. Changes in foetal protein and energy fitted a multi-phasic regression that consisted of two linear equations. Similarly, changes in foetal fat and water contents fitted a multi-phasic regression that consisted of two linear equations, indicating that protein and energy growth accelerated after days 95 and 97 of gestation, respectively, with increases in fat and water accelerating after days 127 and 96 of gestation, respectively. Foetal protein and energy accretions were 0.04 g?day^?1 and 0.001 MJ?day^?1 before days 95 and 97 of gestation, respectively, and increased to 0.31 g?day^?1 and 0.009 MJ?day^?1 after days 95 and 97 of gestation, respectively. Fat and water accretions were also 0.012 g?day^?1 and 0.15 ml?day^?1 before days 127 and 96 of gestation, respectively, and increased to 0.104 g?day^?1 and 1.29 ml?day^?1 after the respective days of gestation. Protein needs for tissue protein gain increased ~8-fold after day 95 of gestation. Results of this study indicate that the growth of the foetus and foetal tissues occur at different rates during gestation and points to a two-phase feeding strategy before and after day 95 of gestation for pregnant grasscutters.     

A cross-sectional survey of Thoroughbred stud farm management in the North Island of New Zealand

AIM: To obtain initial baseline data on the management of Thoroughbred stud farms in the North Island of New Zealand.

METHODS: Data on the management of Thoroughbred stud farms were collected from a sample of 22 stud farms located in the south Auckland/Waikato region (n=15) and lower North Island (n=7) of New Zealand, using a face-to-face survey. The studmaster provided information on the size, scope and management of the farms during the 2004/2005 breeding season. Analysis was based on the location of the farm and size of the breeding operation (number of resident mares).

RESULTS: Effective farm size ranged from 20 to 526 ha and averaged 167 (standard error (SE) 36) and 88 (SE 49) ha in the south Auckland/Waikato and lower North Island areas, respectively. Some farms in the Auckland/Waikato region stood shuttle stallions. The median number of stallions per farm was three (range 0.9), and the median mare-to-stallion ratio was 43 (range 10.250). The farms had a mean of 50 (range 7.180) wet mares and 21 (range 0.100) dry mares. The number of mares per breeding stallion increased with increasing size of breeding operation (p=0.04), being 28 (95% confidence interval (CI) = 10.56) vs 40 (95% CI=16.74) vs 74 (95% CI=44.113) for moderate (≤70 mares), medium (90–199 mares) and large (≥200 mares in total) operations, respectively. Seventy-one percent of farms aimed to breed dry mares early in the breeding season, and used a combination of lights, hormone therapy, and rising plane of nutrition to achieve this.

Foaling took place in foaling paddocks monitored using a night foaling attendant (17/22) or with foaling alarms (5/22). At birth, 17/22 studmasters routinely administered antibiotics, 14/22 administered tetanus antitoxin, 9/22 administered an enema to foals, and 2/22 did not routinely administer prophylactic treatments. Weaning occurred at 5 (range 3.7–7) months of age, and foals were confined to a box for 1–2 weeks on 16/22 farms. Weaned foals were drenched with anthelmintics every 7 (range 4–9) weeks, and were fed 2.9 (range 1–6) kg of concentrate feed while at pasture until intensive management associated with preparation of the horses for auction began 13 (range 6–20) weeks before the yearling sales. Eight farms weighed the weanlings, at least monthly, to monitor growth.

CONCLUSIONS AND CLINICAL RELEVANCE: The management of Thoroughbred horses was relatively consistent throughout the regions surveyed. Utilisation of breeding stallions tended to be more efficient on the larger stud farms in the south Auckland/Waikato region. Even though foals are grown at pasture they are often provided with large quantities of concentrate feed.     

Inactivated oil emulsion vaccines from selected clones of Newcastle disease virus

Summary

The immunogenicity of oil emulsion (OE) vaccines prepared from two selected clones of a Nigerian strain of Newcastle disease virus and two commercial vaccine strains were compared. Geometric mean haemagglutination inhibition titre was lowest in OE‐Lasota, although all four vaccines gave 100% protection against clinical Newcastle disease. The use of OE vaccines is recommended for commercial use in Nigeria.     

Flubendazole metabolism and biotransformation enzymes activities in healthy sheep and sheep with haemonchosis

Bártíková, H., Křížová, V., Lamka, J., Kubíček, V., Skálová, L., Szotáková, B. Flubendazole metabolism and biotransformation enzymes activities in healthy sheep and sheep with haemonchosis. J. vet. Pharmacol. Therap . 33 , 56–62.
The aim of this project was to study the influence of haemonchosis, a common parasitic infection of small ruminants caused by Haemonchus contortus , on the activity of biotransformation enzymes and on in vitro flubendazole (FLU) biotransformation in liver and small intestine of lambs ( Ovis aries ). Twelve lambs were divided into three groups: non-infected animals, animals orally infected with larvae of H. contortus ISE strain for 7 weeks and for 11 weeks. At the end of the experiment, hepatic and intestinal subcellular fractions were prepared and used for assays of biotransformation enzymes activities and FLU metabolism testing. The activities of hepatic cytochromes P450, flavine monooxygenases and carbonyl-reducing enzymes were decreased in infected animals. UDP-glucuronosyl transferase activity was significantly lower (by 35%) in 11 weeks infected animals than that in control animals. When in vitro metabolism of FLU was compared in control and infected animals, significantly lower velocity of FLU reduction was found in infected animals. Slower FLU reduction may be beneficial for the haemonchosis treatment using FLU, because FLU will remain longer in the organism and could cause longer contact of parasites with FLU.     

Ethnobotany and analysis of food components of African locust bean (<Emphasis Type="Italic">Parkia biglobosa</Emphasis> (Jacq.) Benth.) in the transitional zone of Ghana: implications for domestication,conservation and breeding of improved varieties

African locust bean is an important non-timber leguminous tree species for food security in Sahelian zones of Africa. Despite its multipurpose uses by local inhabitants, not much is known about its nutritional importance and ethnobotany in Ghana. For this, one thousand farmers randomly selected from five towns in the transitional zone of Ghana were surveyed using participatory rapid appraisal tools and techniques. The major uses of the plant in the survey area include food, medicine and firewood. Men are involved in the collection of the fruits and women process the seed into “dawadawa”, a protein rich condiment. Folk names of the plant in the study area means a mother or helper indicating the importance of the plant in nutrition and food security. The leaf, bark, root and fruit of the plant are used to treat various medical problems including fever, diarrhoea, stomach problems, boils and burns. Bad odour, limited market access, lack of elite genotypes, bush fires and tedious labour operations were the main constraints of African locust bean production in Ghana. Results on the stages of domestication show that African locust bean is in early stages of domestication which suggest that the respondents are aware of the food value and have a sense of ownership of the crop. Proximate composition of the pulp and the dehulled seed was determined using the official method of the Association of Official Analytical Chemists revealed that the pulp contains 2.47 % ash, 2.15 % protein, 1.33 % fat, 6.9 % fibre and 74 % carbohydrates. The dehulled bean contains 3.91 % ash, 20.93 % protein, 26.33 % fat, 4.92 % fibre and 34.18 % carbohydrates. These findings justified urgent need to domesticate, conserve natural populations and to develop improved varieties to ensure food and nutrition security and health in Africa.