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1.
Effect of sericea lespedeza [SL; Lespedeza cuneata (Dum-Cours.) G. Don.] leaf meal feeding was evaluated in two experiments in indoor reared goats with experimental infection of Haemonchus contortus larvae. In the first experiment, ten 8-10 month old male Spanish and Alpine cross kids pair matched for body weight and age were fed SL or bermudagrass [BG; Cynodon dactylon (L.) Pers.] hay one week before infection and were infected with 5000 H. contortus L(3). The animals were maintained on the same diet for the remaining period and were slaughtered 28 days post-infection (DPI) to determine the establishment of incoming infective larvae. Goats fed SL had lower establishment (P<0.05) of H. contortus larvae than that of the control goats fed BG hay. In the second experiment, twenty-five 8-10 months old male Alpine cross, Saanen, Nubian×Saanen and Spanish kids reared in confinement on BG were experimentally infected with 5000 H. contortus L(3). On 35 DPI, the animals were allocated to two groups after blocking by fecal egg count (FEC), and one group was fed SL leaf meal (n=13), and another control group remained on BG (n=12). Four goats/group were slaughtered successively on days 7, 14, and 28 days post SL feeding, except on day 7, when five SL fed goats were slaughtered. Fecal egg counts and blood packed cell volume (PCV) were measured at weekly intervals and worm count, female worm fecundity, worm length and mucosal eosinophils, mast cells and globule leucocytes were measured after slaughter. Goats fed SL had a lower FEC (P<0.05) one week after feeding, as compared to those fed on BG, and the values remained at low level thereafter. Similarly, PCV was also significantly affected by feeding (P<0.01), and feeding and time interaction (P<0.05). However, worm burden, female worm fecundity, parasite length, and mucosal inflammatory cell count were similar between the groups. Feeding SL reduced the establishment of infective larvae and FEC of H. contortus in experimental studies and this plant could be used for biological control of parasite infection under field conditions to limit the harmful effects of the parasites in goats.  相似文献   

2.
Resistance of gastrointestinal nematodes (GIN) to anthelmintic treatment has increased pressure to find alternative, non-chemical control methods. Feeding hay of the high condensed tannin (CT) forage sericea lespedeza [SL; Lespedeza cuneata (Dum-Cours.) G. Don.] to sheep and goats has reduced GIN fecal egg count (FEC) and worm numbers in the abomasum and small intestines. This effect has been reported with both unground (long) and ground hay. Pelleting of ground hay increases ease of storage, transport, and feeding, but heating during the pelleting process could reduce biological activity of CT. Eighteen naturally GIN-infected 5-6-month-old Kiko-Spanish cross bucks were fed pelleted and ground SL hay and ground bermudagrass [BG; Cynodon dactyon (L.) Pers.] hay diets (n=6 per treatment) in a confinement trial. The bucks were fed the ground BG hay (75% of daily intake) plus a pelleted 16% CP commercial goat chow (25% of daily intake) for 3 weeks, after which they were assigned to treatment groups based upon FEC, 12 animals were switched to ground and pelleted SL hay plus goat chow for 4 weeks, and then all animals were fed the BG ration for one additional week. Throughout the trial, feces and blood were collected from individual animals weekly to determine FEC and blood packed cell volume (PCV), respectively. All goats were slaughtered at the end of the trial, with adult worms in the abomasum and small intestines recovered, counted, and identified to species. Both forms of SL hay reduced (P<0.05) FEC in goats relative to BG hay-fed animals, with a greater reduction in goats fed the SL pellets. There was no effect on PCV until the final sampling date, when the SL pellet-fed goats' PCV increased (P<0.05) compared with the other treatments. Feeding pelleted SL reduced (P<0.05) abomasal worms, primarily Haemonchus contortus, relative to the BG hay-fed goats. Worm numbers in the goats fed ground SL hay were intermediate. Pelleting SL hay enhanced its efficacy against parasitic nematodes and may facilitate the broader use of this forage in small ruminant GIN control programs.  相似文献   

3.
The effectiveness of selective anthelmintic treatments and use of nematophagous fungi Duddingtonia flagrans in reducing levels of gastrointestinal nematodes in goats was investigated at Onderstepoort, South Africa. Nineteen (19) naturally infected indigenous male goats, aged 10 months, were separated into four groups and grazed in separate previously ungrazed paddocks for two worm seasons (February 2002-March 2003). Two groups of goats were fed D. flagrans chlamydospores daily and two groups did not receive fungi. The FAMACHA system was used to determine which goats required anthelmintic treatments. Twice as many goats in the no-fungi fed group required treatments as compared with the fungi fed group. Mean FAMACHA scores in the no-fungi fed group were higher during most of the sampling occasions compared to the group fed fungi, but the difference was not significant. The group-mean faecal egg counts and PCV% were comparable between the two treatment groups throughout the study. Haemonchus was the predominant parasite genus in composite group faecal cultures. Group-mean body weights and body condition scores were higher for the no-fungi fed group from May 2002 up to the end of the study, though statistical differences were not significant. Mean worm burdens indicated that the most abundant species infecting animals were Haemonchus contortus and Trichostrongylus spp. and were higher in the fungi fed group. More animals required individual anthelmintic treatments in the no-fungi fed group. The requirement for extra treatments in the no-fungi fed group must, however, be considered against the financial cost of the fungi, the requirement of daily feeding of the fungi, the lower performance and higher worm burdens in the fungi fed group.  相似文献   

4.
Two experiments investigated the efficacy of the legume Hedysarum coronarium (sulla), which contains condensed tannins (CTs), for reducing gastrointestinal nematode infections relative to lucerne. Experiment 1 was aimed to show whether the lower faecal egg count (FEC) and larval establishment previously reported in lambs grazing sulla were due to direct effects of the forage on Ostertagia circumcincta and Trichostrongylus colubriformis or were mediated through an enhanced immune response. Experiment 2 evaluated the impact of feeding sulla relative to feeding lucerne (Medicago sativa), before, at, or after larval challenge on subsequent FECs and nematode burdens. In experiment 1, 64 Romney lambs were fed either freshly cut lucerne or sulla (32 lambs per herbage) for the duration of the trial. Within each herbage there were four treatment groups (n=8 per group). Initial levels of immunity were assessed in uninfected (UN) lambs which were maintained parasite-free until challenged with 15,000 O. circumcincta and 15,000 T. colubriformis larvae on day 63, and slaughtered on day 81. The other three treatment groups were trickle-infected with each of 5000 O. circumcincta and 5000 T. colubriformis larvae three times per week from day 1 to 35. Non-steroid infected (CONTROL) and steroid-treated (STER) groups were treated with anthelmintic on day 49 and challenged with 15,000 O. circumcincta and 15,000 T. colubriformis on day 63 and slaughtered on day 81. The STER lambs were given dexamethasone trimethylacetate from day 49 to 81 to determine effects of immunity on parasite infection. From day 35 an establishment group (EST) on each herbage was fed a common pelleted lucerne diet and slaughtered on day 56 to determine nematode establishment during trickle-infection. Diet did not affect FECs but feeding lucerne increased (P<0.05) numbers of T. colubriformis in CONTROL lambs compared to those fed sulla. O. circumcincta numbers were lower (P<0.05) in UN lambs fed sulla than lucerne. The sulla diet was associated with higher (P<0.05) antibody titres against secretory-excretory antigens to adult O. circumcincta and to adult and larval T. colubriformis, so there appeared to be some immunogenic response to the sulla diet but effects upon T. colubriformis numbers were not significant. The second experiment involved 48 Romney lambs grazing conventional pasture which were infected with 10,000 each of O. circumcincta and T. colubriformis larvae either 7 days before, 7 days after, or at the time they commenced grazing either sulla or lucerne. Lambs which grazed sulla had lower (P<0.05) FEC and lower (P<0.05) O. circumcincta burdens than lambs which grazed lucerne but timing of infection had no effect on FEC or worm burdens. T. colubriformis numbers were not affected by treatment or herbage. In conclusion, the sulla diet resulted in lower O. circumcincta numbers compared to lucerne outdoors and some evidence of an immunogenic response was obtained indoors. However, neither the herbage nor the immunogenic response reduced T. colubriformis numbers in either experiment.  相似文献   

5.
The benefit of gastrointestinal nematode control in cross-bred goats in the dry area of Sri Lanka was studied throughout 1 year by comparing the performances of three groups: group 1 animals (n = 11) were left untreated against gastrointestinal nematodes; group 2 animals (n = 11) were given monthly anthelmintic treatment. doramectin, at the dose rate of 300 microg/kg bodyweight during the entire study period; group 3 animals (n = 11) were also given monthly doramectin treatment at the dose rate of 300 microg/kg bodyweight but only during the rainy months, October to January and again once in April. All three groups were turned out together on to communal pasture. Tracers were used for the monthly estimation of gastrointestinal nematode burdens. Four untreated animals and a group 3 animal suffered from parasitic gastroenteritis during the study period. When compared with the controls, the treated groups had significantly lower gastrointestinal nematode infection as indicated by faecal egg counts (P<0.01). Faecal egg counts in group 3 were significantly higher than those in group 2 (P < 0.01). When compared with the controls, the treated groups had significantly greater weight gains (P< 0.05). Haemonchus contortus and Trichostrongylus colubriformis were the predominant gastrointestinal nematodes identified from tracers. The worm burden varied according to the rainfall pattern, with very minimal transmission during the dry period which extends from May to August. Under the conditions of this study, the monthly anthelmintic treatments increased weight gains and prevented parasitic gastroenteritis of goats in the dry zone of Sri Lanka.  相似文献   

6.
To investigate the effect of feeding forage legumes containing condensed tannins (CT) on internal parasitism, red deer calves were fed either lucerne (Medicago sativa; 0.1 per cent CT), birdsfoot trefoil (Lotus corniculatus; 1.9 per cent CT) or sulla (Hedysarum coronarium; 3.5 per cent CT) and trickle-infected with deer-origin gastrointestinal nematode and lungworm (Dictyocaulus sp.) larvae for 5 weeks, then slaughtered at 7 weeks. There was a significant negative linear relationship between dietary CT concentration and abomasal nematode burdens. No significant differences in faecal egg counts, lungworm burdens or voluntary feed intake were found. Deer fed sulla had higher liveweight gain, carcass weight and carcass dressing-out percentage, higher serum total protein and albumin concentration and lower serum gastrin concentration and faecal lungworm larval count, compared with lucerne-fed deer. Inclusion of sulla in diets for young red deer may reduce the impact of internal parasites and/or reduce the dependence on anthelmintic treatment.  相似文献   

7.
The objective of three experiments was to determine the impact of supplementing sericea lespedeza (Lespedeza cuneata; SL) in three concentrations in a loose or pelleted diet on gastrointestinal nematodes (GIN) in small ruminants. Experiments on lambs were conducted at the USDA, Agricultural Research Service in Booneville, AR (Exp. 1) and at Louisiana State University in Baton Rouge, LA (Exp. 2); an experiment on goat kids occurred at University of Maryland-Eastern Shore (Exp. 3). Exp. 1 used crossbred hair sheep lambs naturally infected with GIN that were randomly allocated to diets containing 0, 25, 50, and 75% SL diets (n=11 or 12/diet). Exp. 2 consisted of Haemonchus contortus-inoculated crossbred wool breed lambs that were blocked by gender and FEC and randomly assigned to 0, 25, 50, or 75% SL diet (n=8/diet). Fecal egg counts (FEC) and blood packed cell volume (PCV) were not influenced by SL supplementation in Exp. 1 and 2. Exp. 3 consisted of naturally GIN infected Boer crossbred goat kids in individual pens. Kids were blocked by FEC and randomly allotted to treatments of 0, 20, 40, or 60% SL with 9-13 goats/diet. The more SL fed, the greater the reduction in FEC (P<0.001). There was an increase in PCV in SL fed goats (P<0.001). Larval speciation at the end of the experiment indicated that feces from control animals produced 43% H. contortus larva while 20, 40 and 60% SL resulted in 39%, 35% and 31% H. contortus larvae, respectively. Feeding dried SL may be less effective in lambs than kids, though concurrent studies must be conducted to confirm this.  相似文献   

8.
Goat production is increasing in the United States due to high ethnic demand, but infection with gastrointestinal nematode (GIN) parasites is a major constraint to the industry. Increasing GIN resistance to chemical anthelmintics worldwide has led to the development of alternative control strategies, including use of forages containing condensed tannins (CT). An experiment was designed using infected and dewormed male kids (Kiko x Spanish, 6 mo old, 18.9 +/- 3.25 kg) fed diets containing 25% concentrate and either 75% sericea lespedeza [SL; Lespedeza cuneata (Dum-Cours.) G. Don], a high CT forage (87 to 181 g of CT/kg), or 75% bermudagrass [BG; Cynodon dactylon (L.) Pers.] hay (n = 10/treatment). The kids were weighed every 14 d, and fecal and blood samples were taken weekly for fecal egg counts and packed cell volume determination, respectively. Fecal cultures were processed every 14 d to determine CT effect on larval development. At slaughter, adult GIN were collected from the abomasum and small intestines for counting and speciation. Blood samples were also analyzed for plasma urea-N, and ruminal VFA and pH were determined. The infected SL-fed kids had consistently lower (P < 0.05) fecal egg counts than the infected BG goats throughout the trial and greater (P < 0.05) packed cell volume beginning by d 77. Average daily gain was greater (P < 0.001) in kids fed SL- than BG-based diets, regardless of infection status (104.3 +/- 5.0 and 75.5 +/- 4.8 g/d, respectively). Total VFA and acetate concentrations were greater (P < 0.001) in the BG- than in SL-fed goats, whereas propionate levels were unaffected by diet. Acetate:propionate ratio (P = 0.01) and plasma urea-N (P = 0.03) levels were greater in BG-fed goats, whereas rumen pH was greater (P < 0.001) in the SL-fed goats. Feeding SL hay can reduce GIN infection levels and increase performance of goats compared with BG hay.  相似文献   

9.
Groups of 10 goats, harbouring both naturally acquired and experimental infections of gastrointestinal nematodes, were drenched with either levamisole (5 mg kg-1), albendazole (3.8 mg kg-1) or parbendazole (15 mg kg-1), or remained untreated. Haemonchus contortus was the numerically dominant infection, with Strongyloides papillosus, Trichostrongylus colubriformis and Oesophagostomum columbianum also present. At 5-6 days post-treatment, goats were killed and necropsied. Post-mortem worm counts showed that the reduction in mean total worm burdens was 57.4% in levamisole-treated animals, 71.1% in the albendazole group and 85.1% in the parbendazole group. Reductions for H. contortus were 80.2, 87.9 and 83.9% in the levamisole-, albendazole- and parbendazole-treated groups, respectively. These data indicate that the anthelmintics in question are not being applied at an adequate dose rate for goats, and/or resistance to anthelmintics is occurring in the field in Pernambuco State, northeast Brazil.  相似文献   

10.
AIM: To assess the in vivo anthelmintic activity of condensed tannins (CT) in the forage species Dorycnium rectum and Medicago sativa, and in an extract from grape (Vitus vinifera) seeds (GSE), against two species of parasite, Teladorsagia (Ostertagia) circumcincta and Trichostrongylus colubriformis, at different stages of their life cycle, in sheep that were parasite-na?ve or previously exposed to nematodes. METHODS: In Trial 1, a factorial treatment structure was used to compare faecal nematode egg counts (FEC) and worm burdens in 40 weaned Romney lambs fed either the CT-containing forage D. rectum (12% dry matter; DM) or M. sativa (lucerne; 0.2% DM). Twenty na?ve and 20 previously-exposed lambs were drenched free of parasites then reinfected with known species and numbers of parasites, and housed in pens indoors on a diet of lucerne pellets and chaffed hay. Groups of lambs (n=5 lambs per group) were fed one of the forages over one of two time periods within the parasite's life cycle. Six to nine days after the last feeding of fresh forages, faecal samples were collected for FEC, and all lambs were slaughtered and worm counts conducted. In Trial 2, 12 Suffolk x Romney lambs were surgically implanted with an abomasal cannula and then housed indoors in metabolism crates. After infection with parasites, six lambs were infused continuously over a 14-day period with a commercially available CT GSE (96% DM, made up to 34 g/L in water); the remaining lambs were infused with water. During infusion, samples were collected for egg hatch and larval development assays. After infusion, samples were collected for FEC, and all lambs were slaughtered and worm counts conducted. RESULTS: In Trial 1, there was a significant (p<0.001) difference in burdens of O. circumcincta between na?ve lambs and those previously exposed to parasites, but no other differences were recorded. In Trial 2, lambs infused with GSE had significantly (p<0.05) fewer T. colubriformis at slaughter and significantly (p<0.001) fewer eggs hatched in the egg hatch assay (EHA) than for lambs infused with water. Overall, the differences attributable to GSE were small in magnitude, being an 11% drop in egg hatch, and an 18% drop in numbers of adult T. colubriformis after 14 days of continuous infusion. No other differences were recorded. CONCLUSION: The results indicate that the in vivo anthelmintic activity of these CT sources is, at best, modest and is unlikely to be of any practical value. Further, these data emphasise that in vitro activity is an unreliable indicator of in vivo efficacy for CT-containing forages and extracts.  相似文献   

11.
为了研究长期饲喂高精料日粮对泌乳期山羊血液生化指标和糖代谢的影响,选择8只安装永久性瘤胃瘘管的健康经产泌乳中期山羊,分别饲喂精粗比为40∶60 (low concentrate, LC,n=4) 和60∶40 (high concentrate, HC,n=4)的日粮。实验期共8周,实验期间采集瘤胃液,血液;实验结束时采集肝脏,肌肉,脂肪组织置于液氮速冻后于-70℃保存待测。结果显示,饲喂高精料日粮2周后山羊瘤胃液pH显著降低,采食后瘤胃液pH持续低于5.8超过3 h,8周后瘤胃液pH升高维持在6.0以上,但仍低于LC组山羊。与LC组山羊相比较,HC组山羊血液中葡萄糖、游离脂肪酸含量均升高(P<0.05,P=0.071),谷草转氨酶含量有上升的趋势(0.05相似文献   

12.
The efficacy of a morantel sustained release bolus (MSRB) for control of gastrointestinal nematodes in yearling steers was evaluated over a 6-month grazing period commencing on 26 March 1982. Three groups of 15 steers were allotted to the following treatments: Group 1 -- one MSRB at start of trial; Group 2 -- one therapeutic dose of thiabendazole at start of trial; Group 3 -- untreated control. The treatment groups were grazed separately. Parasite egg counts (EPG), herbage larval counts, pepsinogen levels and weight gains were monitored. Every other month, sets of 2 parasite-free tracer calves were placed in the pasture grazed by each treatment group and allowed to graze for 3 weeks before being subsequently necropsied for worm counts. At the end of the trial, 6 animals from each group were also necropsied for worm counts. The MSRB treatment resulted in significantly lower egg counts, fewer infective larvae on pasture, lower pepsinogen levels and lower worm burdens in tracer calves than was the case for the untreated group, but generally the levels were not significantly different from those associated with the thiabendazole treatment. The mean weight gain for the MSRB treated steers showed a significant advantage (70.9 lb) over the untreated animals, but was not significantly different from those which received thiabendazole. Total worm counts at the end of the trial were not different from any treatment group.  相似文献   

13.
本试验选取21头10月龄、体重26kg左右的湘东黑山羊,随机分成3组,其中A组为对照组,饲喂基础日粮,B组和C组为试验组,分别在饲喂基础日粮的基础上,补饲尿素含量为7%和10%的尿素糖蜜舔砖,以研究尿素糖蜜舔砖对山羊增重效果的影响。结果表明:补饲尿素糖蜜舔砖后,湘东黑山羊营养状况大大改善,增重速度得到不同程度的提高。补饲舔砖的B、C试验组日增重分别为0.12kg和0.15kg,比对照组分别高50%和87.5%,试验C组比试验B组高2 5%,经方差分析差异及显著(P<0.01)。试验B、C组中每只羊比对照组分别多收入8.34元和17.13元。从而也得出10%尿素添加比7%尿素添加的舔砖补饲山羊的效果要好。  相似文献   

14.
Background: It is well known that feeding a high concentrate(HC) diet to lactating ruminants likely induces subacute ruminal acidosis(SARA) and leads to a decrease in milk fat production. However, the effects of feeding a HC diet for long periods on milk fatty acids composition and the mechanism behind the decline of milk fat still remains poorly understood. The aim of this study was to investigate the impact of feeding a HC diet to lactating dairy goats on milk fat yield and fatty acids composition with an emphasis on the mechanisms underlying the milk fat depression. Seventeen mid-lactating dairy goats were randomly allocated to three groups. The control treatment was fed a low-concentrate diet(35% concentrate, n = 5, LC) and there were two high-concentrate treatments(65% concentrate, HC), one fed a high concentrate diet for a long period(19 wks, n = 7, HL); one fed a high concentrate diet for a short period of time(4 wk, n = 5, HS). Milk fat production and fatty acids profiles were measured. In order to investigate the mechanisms underlying the changes in milk fat production and composition,the gene expression involved in lipid metabolism and DNA methylation in the mammary gland were also analyzed.Results: Milk production was increased by feeding the HC diet in the HS and HL groups compared with the LC diet(P 0.01), while the percentage of milk fat was lower in the HL(P 0.05) but not in the HS group. The total amount of saturated fatty acids(SFA) in the milk was not changed by feeding the HC diet, whereas the levels of unsaturated fatty acids(UFA) and monounsaturated fatty acids(MUFA) were markedly decreased in the HL group compared with the LC group(P 0.05). Among these fatty acids, the concentrations of C15:0(P 0.01), C17:0(P 0.01), C17:1(P 0.01), C18:1 n-9 c(P 0.05), C18:3 n-3 r(P 0.01) and C20:0(P 0.01) were markedly lower in the HL group, and the concentrations of C20:0(P 0.05) and C18:3 n-3 r(P 0.01) were lower in the HS group compared with the LC group. However, the concentrations of C18:2 n-6 c(P 0.05) and C20:4 n-6(P 0.05) in the milk fat were higher in the HS group. Real-time PCR results showed that the m RNA expression of the genes involved in milk fat production in the mammary gland was generally decreased in the HL and HS groups compared with the LC group. Among these genes, ACSL1, ACSS1 2, ACACA, FAS, SCD, FADS2, and SREBP1 were downregulated in the mammary gland of the HL group(P 0.05), and the expressions of ACSS2, ACACA, and FADS2 m RNA were markedly decreased in the HS goats compared with the LC group(P 0.05). In contrast to the gene expression, the level of DNA methylation in the promoter regions of the ACACA and SCD genes was increased in the HL group compared with the LC group(P 0.05). The levels of ACSL1 protein expression and FAS enzyme activity were also decreased in the mammary gland of the HL compared with the LC group(P 0.05).Conclusions: Long-term feeding of a HC diet to lactating goats induced milk fat depression and FAs profile shift with lower MUFAs but higher SFAs. A general down-regulation of the gene expression involved in the milk fat production and a higher DNA methylation in the mammary gland may contribute to the decrease in milk fat production in goats fed a HC diet for long time periods.  相似文献   

15.
Although the use of tanniferous plants or condensed tannins as an alternative to anthelmintics to control gastrointestinal nematodes has been largely documented in sheep, studies remain scarce in goats. The objective of this study was therefore to assess the possible impact of condensed tannins in goats infected with adult Haemonchus contortus. Two groups of cull goats were experimentally infected with 10.000 L3 of H. contortus. After 4 weeks, quebracho extracts, representing 5% of the diet DM, were administered for 8 days to one of the two groups. Goats of the second group remained as controls. One week after the end of quebracho administration, the goats were euthanised. Individual egg excretion and pathophysiological parameters were measured weekly during the study. At the end of the study, worm counts were assessed and histological samples from the abomasa were taken to count the numbers of mucosal mast cells, globule leukocytes and eosinophils. The administration of tannins was associated with a significant decrease in egg excretion, which persisted until the end of experiment. This reduction was not associated with any difference in worm number but with a significant decrease in female fecundity. No significant changes in the mucosal density of the three inflammatory cell types were detected between the two groups. These results indicate that the major consequence of tannin consumption in goats is a reduction in worm fecundity and egg output, which does not seem related to significant changes in the local mucosal response.  相似文献   

16.
Forty-one, 10-week-old newly weaned goats were randomly allocated into two groups, namely control (n=22) and treated (n=19). Kids in both groups were fed Rhodegrass hay ad libitum that contained < 0.1 mg/kg DM cobalt and 150 g/day of a commercially prepared ruminant concentrate that contained approximately 0.12 mg/kg DM cobalt. This diet provided the minimum daily requirement of cobalt as specified for sheep. The treated goats were supplemented with bi-monthly subcutaneous injections of 2000 microg of hydroxycobalamin. All goats were weighed and blood samples collected monthly for haematological, clinical biochemical and serum vitamin B12 analysis. After a 10-month experimental period the goats were slaughtered. The control animals exhibited significantly (P<0.05) lower weight gains, and had dry scruffy hair coats. In addition, there was a decline in erythrocyte counts, mean haemoglobin, packed cell volume, mean corpuscular volume, mean corpuscular haemoglobin and mean corpuscular haemoglobin concentration. Controls also exhibited significantly (P<0.05) lower levels of total serum proteins and elevated levels of serum alkaline phosphatase compared to treated goats. Fourteen (63.6%) of the control goats developed pathology consistent with reported field cases of hepatic lipidosis associated with low liver levels of cobalt. Only one (5.3%) of the treated goats developed hepatic lipidosis. Contrary to previous reports that suggested that goats are less sensitive to low levels of dietary cobalt than sheep, it is apparent that this is not the case with Omani goats. This is the first report of the induction of hepatic lipidosis in goats due to feeding low levels of cobalt in their diet.  相似文献   

17.
The use of tanniferous plants or tannins represents one alternative approach to the control of gastrointestinal parasites in ruminants but most data have been obtained in sheep. The current study was therefore performed in goats with two objectives: firstly, to investigate the effects of condensed tannins (CT) on adult populations of Trichostrongylus colubriformis and Teladorsagia circumcincta; secondly, to examine their effects on the establishment of infective larvae of these two species. In experiment 1, two groups of kids were infected with 6 000 L3 of T. colubriformis and 6 000 L3 of T. circumcincta. After 7 weeks, quebracho extracts were administered per os for 8 days to one group. A comparable group which did not receive tannins was included as the control. The kids were slaughtered on week 11. Parasitological and pathophysiological parameters were measured weekly. Worm counts were assessed and mast cells, globule leukocytes and eosinophils were counted in the abomasal and intestinal mucosae. Tannin administration was associated with a decrease in egg excretion, and a decrease in female fecundity, but with no changes in worm numbers. These changes were associated with an increased number of intestinal mast cells. In experiment 2, 24 goats were used according to a 2 x 2 factorial design, depending on infection and tannin administration. Two groups were either infected with 6 000 L3 of T. colubriformis or T. circumcincta. Within each group, the goats were either drenched or undrenched with tannin extracts. Pathophysiological parameters were measured weekly. Twelve days after the cessation of tannin administration, the goats were slaughtered. Worm counts and female worm fecundity were determined. Tannin consumption was associated with a significant reduction (P < 0.01) of Trichostrongylus populations and a close to significant reduction for Teladorsagia. No effect on fecundity was observed. Our results (1) confirm the consequences of condensed tannins on nematodes in goats as in sheep and (2) indicate divergent effects depending on the parasitic stage exposed to the condensed tannins.  相似文献   

18.
The effect of feeding a coarsely ground meal (COARSE) and a finely ground pelleted diet with 1.8% (as-fed basis) added formic acid (ACID) was compared with feeding a standard finely ground pelleted diet (STD) on the gastrointestinal ecology of growing pigs at different intervals after feeding. One hundred five castrated male growing-finishing pigs (initial BW 27 kg) were used. At a BW of 63 kg, 60 pigs were killed 0.5, 2.5, 4.5, 6.5, and 8.5 h after feeding, and samples from the gastrointestinal tract (GIT) were obtained. The remaining 45 pigs were kept on the experimental diets to a BW of 99 kg. Feeding the three diets resulted in a similar pattern of gastric pH with time, (i.e., highest pH values 0.5 h after feeding and decreasing values at the following sampling times, to reach a value of 2.12 at 8.5 h after feeding). The pH of the gastric digesta of pigs fed the ACID diet was below 4 at all sampling times, whereas the digesta from the other two dietary groups had values above pH 4 at the first sampling times. Feeding the ACID diet decreased the counts of total anaerobes in the proximal GIT (P < or = 0.007), and of lactic acid bacteria (P < or = 0.001), enterobacteria (P < or = 0.02), and yeasts (P < or = 0.01) along the GIT compared with feeding the other two diets. Feeding the COARSE diet stimulated the growth of total anaerobes and lactic acid bacteria in the stomach and distal small intestine increased the microbial diversity mainly in the stomach (P = 0.001), compared with feeding the other two diets (P < or = 0.09), and decreased the number of enterobacteria in the cecum compared with the STD diet (P = 0.03), with the same tendency in the mid-colon (P = 0.07). The concentration of lactic acid in the stomach was highest in the pigs fed the COARSE diet compared with the other two groups (P < 0.05). The concentration of formic acid was highest in the stomach and all segments of the small intestine of the pigs fed the ACID diet compared with those fed the STD and COARSE diets (P < 0.05). The results from this study suggest that feeding a coarsely ground diet and a finely ground diet with added formic acid affect the gastrointestinal ecology of pigs mainly by changing the environment in the proximal GIT. The presence of organic acids in the proximal GIT is a crucial factor contributing to the decrease in the number of enterobacteria along the GIT. The time after feeding at which samples are taken to measure characteristics describing the gastrointestinal ecology affects the results from the stomach and small intestine.  相似文献   

19.
A study was conducted to examine the role of nutrition in the development of gastrointestinal (GI) parasitism, performance and pathophysiology of parasitism in female lambs. Forty-four months old ewe lambs received for 6 weeks 0, 1500 or 7000 L(3) larvae of Teladorsagia circumcincta in two doses per week. The animals were given access to a pelleted diet to meet energy requirements for gaining weight close to their potential (H) or approximately 50% of it (L). The level of protein in the diet was 20-30% above requirements for both planes of nutrition.Measurements of body weight, serum pepsinogen concentration and faecal egg counts were taken at weekly intervals. All animals were slaughtered 2 weeks after the last larval dosing for estimation of worm count, carcass composition and reproductive tract development.Voluntary intake of infected animals decreased by approximately 10%. Both nutrition and infection influenced lamb performance and carcass composition. However, no direct effects on reproductive tract parameters due to the presence of infection were observed.The level of L(3) infection showed a significant effect not only on faecal egg counts and on worm burden, as it could be expected, but also on the proportion of females to males, which increased significantly with the level of infection.While the plane of nutrition did not show a significant effect on faecal egg counts or on worm burden, surprisingly, both female worm size and their fecundity decreased significantly with the level of nutrition. This response was accompanied by a significant increase in the concentration of circulating eosinophils suggesting that the immune response of lambs consuming high levels of energy was enhanced compared to that of lambs kept on a restricted diet.Results herein show that in young female lambs fed on adequate levels of protein, an improvement in energy supply does not only improve carcass characteristics but clearly enhances the development of resistance to GI nematodes infection. This may have decisive management implications for the control of parasitic infections in sustainable production systems.  相似文献   

20.
Over a period of 1 year, from May 1982 to April 1983, the gastrointestinal tracts of 240 camels were examined for the presence of parasitic helminths. The study quantifies the prevalence of gastrointestinal helminths and the seasonal fluctuations in intestinal worm burdens and faecal worm egg counts. Among the three species of cestodes and eight species of nematodes which were recorded for the first time from Kuwait, Trichostrongylus probolurus (93.8%), T. colubriformis (34.2%) and Stilesia vittata (30.0%) were the most prevalent in the small intestine and Camelostrongylus mentulatus (59.6%) in the abomasum. Estimation of the intestinal worm burdens and faecal worm egg counts showed that Trichostrongylus infections were by far the most predominant. The highest worm and egg counts were recorded in June and August, during the hot dry season. This rise is attributed to infections acquired from February to April, during the cool wet season. Possibly the most effective control can be achieved by a critical treatment at the end of the wet season coinciding with the first rise in nematode population.  相似文献   

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