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1.
Lovemore C Gwiriri Godfrey Manyawu Promise B Mashanda Irenie Chakoma Siboniso Moyo Charles Chakoma 《African Journal of Range and Forage Science》2016,33(3):155-163
The effect of replacing commercial supplements with isoenergetic and isonitrogenous velvet bean-, cowpeaand lablab-based supplements on milk yield, milk quality and economic returns in smallholder crossbred dairy cows was investigated in the 2013 and 2014 dry seasons. Using 3 × 3 Latin square designs, nine multiparous Red Dane, Guernsey and Holstein-Friesian crosses in mid-lactation (130 ± 19 d) were offered forage legume-based supplements for 63 d at 0.5 kg per litre of milk produced. Milk quantity and quality were significantly (P < 0.05) different among supplements in both seasons. Cows fed commercial supplements had higher milk yield than cows fed forage legume supplements. Milk fat content was significantly (p < 0.05) higher in cows fed lablab-based supplements than cows fed other supplements. Milk protein, total solids and lactose content of cows fed commercial supplements was significantly (p < 0.05) higher than those fed forage legume-based supplements, although protein content was similar to cows fed lablab-based supplements. Dietary gross margins were higher for cows fed velvet beanand lablab-based supplements by 17% and 16.5%, respectively. Based on supplement, production costs per litre of milk was higher by 28% and 23% using commercial supplements compared to velvet bean and lablab supplements, respectively. 相似文献
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Abstract A two‐year study was conducted in lightly grazed areas of Matopos Research Station, Zimbabwe, to evaluate the impact of widely spaced trees on understorey grass composition, yield and quality. The study trees were Terminalia sericea and Acacia karroo. Ordination techniques using grass density and biomass as indices separated quadrats according to soil type but not grass species according to understorey or open areas or according to tree species. Grass yield under tree crowns was similar to open areas, in contrast with most reports where understorey areas had higher yields. The high understorey grass quality that has been reported from savanna areas exhibiting grass composition differences was not expressed. Selective grazing of palatable perennial grasses growing in association with tree crowns and their eventual replacement by low‐yielding and less‐palatable grasses that normally grow in open areas is proposed as an explanation of the unique tree‐grass interaction scenario of this study. In areas where this replacement has occurred, recovery may require management interventions. 相似文献
3.
Tsotetsi Ana Mbokeleng Njiro Stephen Katsande Tendai Charles Moyo Gugulethu Baloyi Faculty Mpofu Jaison 《Tropical animal health and production》2013,45(3):751-761
Tropical Animal Health and Production - The present study was conducted to determine the prevalence and distribution of gastrointestinal helminths, to detect the presence of anthelmintic resistance... 相似文献
4.
Tick control methods used by resource-limited farmers and the effect of ticks on cattle in rural areas of the Eastern Cape Province,South Africa 总被引：1，自引：1，他引：0
A survey to document tick control methods used by resource-limited farmers in the control of cattle ticks in the Eastern Cape
Province of South Africa was conducted by interviewing 59 cattle farmers using structured questionnaires and general conversation.
Information collected was on external parasites of cattle, their effects and their control methods. Ticks were reported to
be a major problem causing diseases like anaplasmosis (89.8%), babesiosis (55.9%) and ehrlichiosis (16.9%), as well as wounds
that predispose to screwworm infestation, tick worry and teat damage to cows troubling farmers in their farming enterprises.
The main tick control methods were; acaricides provided by government, however 94.9% of the farmers interviewed were of the
opinion that the dip wash is not effective in killing the ticks. As a result, farmers complement the government dipping service
with their own initiatives like spraying with conventional acaricides (22%), household disinfectants such as Jeyes fluid (18.6%),
used engine oil (10.2%), chickens (5.1%), manual removal (5.1%), and pouricides (1.7%). In addition, some farmers also use
plants (6.8%), mainly the leaf of Aloe ferox and the bark of Ptaeroxylon obliquum. The study revealed ticks to be a major problem in the study area. 相似文献
5.
The biological significance of mast cells and angiogenesis in canine melanomas is unclear. Eighty canine melanomas (56 malignant and 24 benign), investigated to determine the relationship between mast cell count (MCC), microvessel density (MVD) and clinicopathology, revealed significantly higher MCC and MVD counts in malignant melanomas. Evaluation of the prognostic significance of MCC and MVD in malignant melanomas showed a significant correlation between MCC and MVD both within and at the edges of the tumour. Multivariate analysis indicated that MCC and MVD were independent predictors of survival but the former was a significantly better prognostic marker. Greater numbers of mast cells and microvessels were found in malignant melanomas of poor prognosis. The findings demonstrate a prognostic significance of MCC and MVD in canine melanocytic tumours. 相似文献
6.
SUMMARY: This study was undertaken to investigate the relationship between date of birth and growth performance of calves born to seasonally-bred range beef cows. Late-born calves exhibited an apparent superiority in preweaning growth over that of their early-born counterparts. This was attributed to a positive residual effect of maternal environment arising from the fact that calves born late were those whose dams had a substantial proportion of the critical last trimester of the gestation period in a favourable season. This advantage soon disappeared and early-born calves gained more weight and at a faster rate between 90 days and weaning. A combination of the effect of weaning stress and unfavourable nutritional environment in the immediate postweaning period had a check on calf growth but late born calves suffered most. It was concluded that, in this environment, nutrition was most limiting to calf growth between weaning and 12 months of age and it was during this period that a clear advantage of early birth of calves appeared; A 1 day delay in BD was associated with a 9.1 kg (P < .01) decrease in net weight change in this period. However, due to compensatory growth, the corresponding figure for the 12 months to 18 months period was an increase of 11.6 kg (P < .01) in weight change. In terms of actual postweaning weights (not age-adjusted), early BD was superior to late BD at all ages except at 18 month. A 1 day delay in BD was associated with a .7 kg reduction (P < .01) in liveweight between 90 days and weaning, a 6.7 kg reduction (P < .01) in actual weaning weight, a 6.8 kg reduction (P < .01) in actual 12 months liveweight, and a non significant (P > .05) 0.7 kg reduction in actual 18 months liveweight. Under seasonal breeding and group management of calves, all animals from a calf crop are expected to go to market at the same time, thereby rendering age-adjustment of liveweights irrelevant. However, the sale of late calves could be delayed by a few months to take advantage of the rainy season and to exploit compensatory growth. The benefit of this practice should, however, be weighed against both the direct cost (of feeding, veterinary care, labour and so on) and the indirect cost - the competition factor -introduced on the next calf crop. ZUSAMMENFASSUNG: Beziehung zwischen Geburtsdatum und Wachstumsleistung von K?lbern saisongedeckter Fleischrinder Sp?tgeborene K?lber zeigten eine scheinbare überlegenheit im Saugperiodenwachstum, was den positiven Restwirkungen maternaler Umwelt zugeschrieben wird, die auf günstige Umwelteinflüsse w?hrend des letzten, dann regenreichen Trimesters der Tr?chtigkeitsperiode zurückzuführen sind. Dieser Vorteil ist bald verschwunden, und frühgeborene K?lber hatten ein rascheres Wachstum zwischen 90 Tagen und dem Absetzen. Eine Kombination von Absetzstre? und ungünstiger Ern?hrungssituation unmittelbar nach dem Absetzen bremste das Jungtierwachstum, wobei sp?tgeborene K?lber den meisten Schaden zeigten. In der gegebenen Umwelt hat mangelnde Ern?hrung den st?rksten begrenzenden Einflu? auf Wachstum zwischen Absetzen und J?hrlingsalter, so da? sich in dieser Periode der Vorteil von frühen Geburten zeigte. Eine Verz?gerung von 1 Tag bei der Geburtszeit führte zu 9,1 kg Verminderung des Nettogewichts-Zuwachses in dieser Periode. Aufgrund kompensatorischen Wachstums ?nderte sich das zwischen 12 und 18 Monaten auf plus 11,6 kg Zuwachs. In bezug auf Jungtiergewichte (nicht alterskorrigiert) waren Tiere mit frühem Geburtsdatum in allen Altersklassen, au?er bei 18 Monaten, überlegen. Eine Verz?gerung von 1 Tag im Geburtsdatum war verbunden mit 0,7 kg Reduktion im K?rpergewichtszuwachs zwischen 90 Tagen und Absetzen, mit einer 6,7 kg Reduktion im Absatzgewicht und 6,8 kg im J?hrlingsgewicht. Das 18 Monate Gewicht war insignifikant um 0,7 kg reduziert. Unter saisonaler Zucht und Management gehen alle Tiere zur selben Zeit auf den Markt, so da? Alterskorrekturen irrelevant sind. Allerdings k?nnte der Verkauf sp?tgeborener K?lber um einige Monate verz?gert werden, um die Vorteile der Regenzeit und des damit verbundenen kompensatorischen Wachstums auszunutzen. Vorteile einer solchen Praxis aber sollten sowohl gegen die direkten (Futter, Veterin?re, Arbeit usw). wie auch gegen indirekte Kosten (Wettbewerb durch die n?chsten K?lber) balanciert werden. 相似文献
7.
This experiment investigated the effect of dietary supplementation with essential oils from Artemisia afra and Moringa oleifera on haemato‐immunological parameters and resistance in Clarias gariepinus (African Sharptooth catfish) (Burchell, 1822) challenged with Aeromonas hydrophila. The experiment lasted for 45 days. Prior to and postchallenge, white blood cells significantly increased (p < .05) from the 3% to 12% M. oleifera and A. afra supplementation. Pre‐challenge, no significant differences (p > .05) in red blood cells, haemoglobin and haematocrit were observed between the control and M. oleifera supplementation, while in the A. afra supplementation, RBC and HCT significantly increased from the 6% to 12%. Postchallenge, RBC, HGB and HCT were significantly lower (p < .05) in the control and the 3% and 6% M. oleifera and A. afra supplementation. Both pre‐ and postchallenge, nitro‐blue tetrazolium levels significantly increased (p < .05) from the 3% to 12% M. oleifera supplementation while no significant differences (p > .05) were observed in lysozyme activity between the control and treatment groups. In A. afra, NBT and lysozyme activities increased significantly (p < .05) from the 6% to 12% supplementation pre‐ and postchallenge. Survival rate increased from the 3% to 12% in M. oleifera and A. afra supplementation groups. Significant kidney histological alterations were noted in the control and the 3% and 6% supplementation of both plants postchallenge, while no major histological changes were observed between treatment groups and the control pre‐challenge. The results demonstrate that EO from M. oleifera and A. afra can improve immunity and enhance survival in C. gariepinus. 相似文献
8.
Njiro SM Kidanemariam AG Tsotetsi AM Katsande TC Mnisi M Lubisi BA Potts AD Baloyi F Moyo G Mpofu J Kalake A Williams R 《Journal of the South African Veterinary Association》2011,82(4):213-218
Two hundred and thirty-nine cattle from Gauteng Province in South Africa were tested for various pathogens causing reproductive diseases includingbovine viral diarrhoea/mucosal disease (BVD/MD) virus, infectious bovine rhinotracheitis/infectious pustular vulvovaginitis (IBR/IPV) virus, Neospora caninum and Brucella abortus usingvarious tests. For BVD/MD virus, 49.37% tested positive, 74.47% for IBR/IPV virus, 8.96% for Neospora caninum and 3.8% for Brucella abortus. The result for Brucella abortus is higher than the national average, possibly due to the small sample size. A high seroprevalence of antibodies to both BVD/MD virus and IBR/IPV virus was evident. These 2 viruses should be considered, in addition to Brucella abortus, when trying to establish causes of abortion in cattle. The clinical significance of Neospora caninum as a cause of abortion in Gauteng needs further investigation. One hundred and forty-three bulls were tested for Campylobacter fetus and Trichomonas fetus, and a low prevalence of 1.4% and 2.1% respectively was found in this study. The clinical implications of these findings are discussed. 相似文献
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1. A study was undertaken to examine the effect of supplementation of diets with fats of different chain length and degree of unsaturation on the performance, carcase characteristics and tissue fatty acid composition of broilers.
2. Three hundred and sixty 19‐day‐old female broilers were fed on diets containing supplemental fat/oil (50 g/kg) in the form of beef tallow (BT) (diet T‐T), soyabean oil (SBO) (diet S‐S), rapeseed oil (RSO) (diet R‐R), marine oil (MO) (diet M‐M) or binary mixtures (0.5:0.5 w/w) of these lipids (diets T‐S, T‐R, T‐M, S‐R, S‐M, and R‐M) to 54 d of age. Food intake, live weight, plucked weight and the lipid concentration and fatty acid composition of abdominal fat pad, liver and breast muscle were measured.
3. Food intake, plucked weight and live weight were greatest for diet T‐T and lowest for diet R‐R. Food conversion ratio was poorest for birds fed on diets containing BT. Lipid concentration in abdominal fat pad was significantly higher in birds fed on diets containing SBO. liver lipid concentration was significantly reduced by diets containing RSO.
4. Abdominal fat pad fatty acid profile was most readily altered by dietary fatty acids. There was a strong correlation between dietary fatty acid composition and tissue fatty acid composition for all fatty acids except C14:0, C20:0, C20: 2n‐6 and C20: 4n‐6. The tissue P/S ratio ranged from 0.40 for diet T‐T to 1.40 for diet S‐S. The n‐6/n‐3 ratio was significantly increased by the inclusion of SBO and decreased by the inclusion of MO.
5. Liver fatty acid profile was least modified by dietary fatty acids. There was an inverse relationship between liver and dietary C20:4n‐6 concentration. Tissue C18:2n‐6 and C20:4n‐6 were highly correlated, suggesting significant interconversion by ?‐6 desaturase in this tissue. The n‐6/n‐3 ratio was significantly increased by inclusion of SBO and significantly decreased by the inclusion of MO.
6. In breast muscle MO‐based diets increased the proportion of n‐3 PUFA at the expense of n‐6 PUFA. The tissue concentrations of C18:ln‐9, C18:2n‐6, C20:ln‐9, C20:5n‐3, C22:5n‐3 and C22:6n‐3 were strongly correlated with dietary fatty acid composition. Muscle and diet P/S and n‐6/n‐3 ratios were highly correlated. 相似文献