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1.
Information on the initial and final weights, length of feeding period, grade of the live animal before slaughter, carcass weight and dressing percentage of 2,498 stall fed Malawi zebu (MZ) and crossbred steers from Southern Region and 2,085 steers from the Central Region of Malawi is analysed. Agricultural and household residues were the basis of the feeding system. The genetic composition of individual animals was not known; weight groups were therefore used as proxies for breed types. Final weights were significantly influenced by breed, month and year when the feeding period was started and breed by month interactions. The mean stall feeding period in the South was 188 days and the average daily gain was 0.59 kg. Steers in the Central Region were fed for 213 days and gained on average 0.50 kg per day. Breed did not exert a significant effect on weight gain. However, when daily gain was compared on the basis of metabolic body size, MZ i.e. smaller steers gained significantly more rapidly than crossbred steers. The dressing percentage of animals from both regions was 52.3%. The carcass weight of crossbred steers was higher than that of MZ steers. It is concluded that an effective fattening system can be based on locally available resources and a similar system could be suitable for other parts of the developing world.  相似文献   

2.
Pasteurella multocida is responsible for a variety of diseases of veterinary importance, including the pig disease progressive atrophic rhinitis (PAR). The feasibility of using the mouse as an experimental model of PAR was evaluated. We experimentally infected the upper respiratory tract of immature mice with a pig isolate of P. multocida that produces the toxin responsible for causing the nasal lesions characteristic of PAR. We tracked the health status and weight gain of these mice for one month following infection, after which the mice were killed and the integrity of the nasal turbinates was examined. Mice infected with P. multocida appeared healthy throughout the study, although the growth rate of these mice was reduced significantly compared with non-infected control animals. Infected animals also demonstrated marked nasal atrophy analogous to that seen in naturally occurring PAR of swine, with shortening and thinning of the turbinate scrolls and inflammatory cell involvement. The mouse therefore provides a convenient model for the further investigation of PAR of swine.  相似文献   

3.
Twelve experimental dogs were monitored for Giardia infection over a 17 month period by both duodenal aspirate and zinc sulphate flotation of faeces. Each animal was found to be Giardia-pos-itive at least twice during this time despite treatment of positive animals. Giardia was frequently identified by both faecal examination and aspirate, but in some cases only one technique proved positive. The results indicated that faecal examinations are as effective as duodenal aspirates in the diagnosis of infection. At the end of the 17 month period six dogs were treated with corticosteroid: three of these treated dogs and one of six untreated animals became positive for Giardia.  相似文献   

4.
Four trials were performed to evaluate the influence of i. m. application of progesterone and estrogens to 444 experimental and control sows and gilts, kept mostly under large-scale production conditions, during the first month of pregnancy, as exerted on the number of born piglets, live born piglets and on the average birth weight of the live born piglet in litter. In the first trial the experimental sows and gilts on the 16th and 17th days of gravidity were applied 25 mg of progesterone (P4) and 12.5 micrograms of estrone (E1), in the second trial in the same phase of gravidity 25 mg of P4 with 1.25 micrograms of estradiol-17 beta (E2) and in the third trial in the identical gestation phase only 12.5 micrograms of E2 per head/day. In the fourth trial, experimental animals were given 0.55 mg of P4 with 0.275 micrograms of E1 per one kg of live weight, for six subsequent days between the 25th and 30th day of gravidity. In all trials the control animals were administered, under the same conditions, only the vehicle. None of the performed trials proved a significant difference in the studied parameters of litters of experimental and control animals (P greater than 0.05). The application of 25 mg of P4 with 1.25 micrograms of E2 on the 16th and 17th days of gravidity per sow/day under the conditions of small-scale production with the extension of the evaluated criteria of litter quality had no significant influence (P greater than 0.5) on the above-mentioned indicators, nor on the average birth weight of the whole litter and on the average number and weight of piglets of experimental sows at weaning. These results document that the verified application of hormonal substances in the above-mentioned phases of the first month of sow and gilt gravidity do not represent, in view of the intensive reproduction of pigs, a suitable procedure.  相似文献   

5.
Femoral head ostectomy was performed in six horses, three ponies, and four cattle for treatment of fractures of the femoral capital physis, coxofemoral luxation, fractured acetabulum, or severe degenerative joint disease. The procedures were performed via a cranial approach that did not involve osteotomy of the greater trochanter. A dorsal approach for femoral head ostectomy via osteotomy of the greater trochanter was evaluated in three healthy adult ponies. Three animals (2 ponies, 1 calf) were euthanatized within a month and one horse was euthanatized at year 2 due to postoperative complications. Nine animals were discharged to owners and six of them fulfilled their intended functions of breeding, milking, and being kept as companions. One horse was lost to follow-up and two horses died of causes unrelated to the surgery. All surviving animals had a residual lameness that was described by owners as mild to moderate. None of the horses were used as riding animals. The mean age and weight of 10 animals that regained weight-bearing locomotion was 3.1 months and 84 kg; for three unsuccessful cases it was 34 months and 174 kg. We concluded that femoral head ostectomy was a viable salvage procedure for large animals with capital femoral physeal fracture, chronic coxofemoral luxation, or acetabular fracture. Surgical prognosis appeared to be favorable in young cattle and fair in young horses or ponies weighing less than 100 kg. Osteotomy of the greater trochanter resulted in superior exposure of the intact coxofemoral joint and allowed easier, less traumatic surgical luxation of the joint to facilitate femoral head ostectomy.  相似文献   

6.
The field efficacy of pour-on formulation of flumethrin 1 per cent was assessed in cattle naturally infested with Psoroptes ovis. In a finishing unit, 18 infested animals were selected, left untreated for one month and examined twice to monitor the progress of the infestation. They were treated twice 10 days apart with a pour-on formulation of flumethrin 1 per cent (2 mg/kg bodyweight). Skin samples were collected from the animals on days 0, 7, 14, 28 and 42 and examined for the presence of live mites. The clinical condition of the cattle was evaluated at the beginning and at the end of the trial using a standardised chart. Bodyweights were recorded on days -32, 0, 28 and 50. In addition the 65 cows in a calving unit were given the same treatment regimen and its efficacy was evaluated on days 0, 7, 14 and 28 in 11 P ovis infested animals. On the day of treatment most of the infested animals had a severe pyodermatitis. From day 7 onwards no live mites were found in the treated animals and there was a marked clinical improvement. The percentage efficacy on day 28 was 100 per cent in both units. In the finishing animals treatment was associated with a marked improvement in daily weight gains between day 0 and day 28.  相似文献   

7.
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   

8.
To study the effect of supplementation of tannin degrading bacterial culture (Streptococcus gallolyticus strain TDGB 406) on growth performance, nutrient utilization and urinary purine derivatives of goats fed on oak (Quercus semicarpifolia) leaves. For growth study, eighteen billy goats (4 month old, average body weight 9.50 ± 1.50 kg) were distributed into three groups of six animals each. The animals of group 1 served as control while animals of groups 2 (T1) and 3 (T2) were given (@ 5 ml/kg live weight) autoclaved and live culture of isolate TDGB 406 (106 cells/ml) respectively. The animals were fed measured quantity of dry oak leaves as the main roughage source and ad libitum maize hay along with fixed quantity of concentrate mixture. The feeding of live culture of isolate TDGB 406 (probiotic) did not affect dry matter intake and digestibility of nutrients except that of dry matter and crude protein, which was higher in T2 group as compared to control. All the animals were in positive nitrogen balance. There was no significant effect of feeding isolate TDGB 406 on urinary purine derivatives (microbial protein production) in goats. The body weight gain and average live weight gain was significantly higher (p = 0.071) in T2 group as compared to control. Feed conversion efficiency was also better in the goats fed on live culture of TDGB 406 (T2). The feeding of tannin degrading bacterial isolate TDGB 406 as probiotic resulted in improved growth performance and feed conversion ratio in goats fed on oak leaves as one of the main roughage source.  相似文献   

9.
A clinical trial was performed to compare the effects of flumethrin and ivermectin treatments of grazing heifers at one farm in central Japan. 64 heifers were randomly allocated into two groups. Flumethrin (1 mg/kg pour on) was applied approximately once every 3 weeks to heifers in one group and heifers in the second group were injected approximately once every month with ivermectin (200 microg/kg; id). Between groups, no significant differences were detected in the proportions of animals that showed parasitemia of Theileria sergenti and conception risks. Significantly lower average log-transformed nematode-egg counts and higher average daily weight gain were observed in the ivermectin-treated group. Animals with higher body weight at the start of grazing and lower log-transformed total nematode-egg and coccidia-oocyst counts had higher odds of conceiving. Animals with ivermectin treatment, lower body weight at the start of grazing and lower log-transformed coccidia-oocyst count had higher daily weight gain. Ivermectin may be more useful in this farm because of the higher productivity for cattle and lower cost for its usage.  相似文献   

10.
The effect of water restriction in Awassi ewes was assessed under two physiological conditions: lactating and dry, over a 3-week-period (August–September, 2002). Eight dry and eight lactating Awassi ewes (with their lambs) were assigned to one of two watering regimes: watered once every three days and daily watering, respectively. Weather data, body weight and rectal temperature were recorded. Venous blood was sampled on the watering day of the water-restricted group, and subjected to haematological, biochemical and electrolytes analysis. Ewes under water restriction lost more weight and had higher packed cell volume, haemoglobin, serum cholesterol, urea, creatinine, total protein and albumin as compared to daily-watered animals. However, lactation seemed to have no significant effect on these serum components. As for blood pH and electrolytes, Na+ and Cl were significantly higher under water restriction; whereas significantly lower K+ and Ca++ but higher pH and Cl were observed in lactating animals. Finally, lower cortisol concentrations were observed in water-restricted animals, warranting further studies on the hormonal adaptation to long term water stress. It was concluded that water restriction induces similar changes in blood physiological indicators in dry and lactating Awassi ewes; while lactation beyond the first month post partum seems to mostly affect blood electrolytes.  相似文献   

11.
选择出生日期5~8 d,5 d初乳期后的荷斯坦母犊牛20头,按照体重相近的原则随机分为两组,每组10头,记为试验组和对照组,试验组饲喂代乳粉,对照组饲喂全乳,其精料、粗料两组均相同,哺乳期45 d,断奶。1月龄和2月龄两组牛平均日增重,第一个月分别为513 g、611 g;第二个月分别为823 g、812 g。试验组生长发育正常,第二个月试验组比对照组饲料转化率稍有提高,表明代乳粉可用来代替全乳饲养犊牛。  相似文献   

12.
The epidemiology of trypanosomiasis in a tsetse-infested range area of Kenya was studied for 2 years in various breeds of sheep and goats. Observations, including infection rates, PCV, temperature and weight loss indicated that the exotic breeds were more susceptible to natural trypanosomal infection than the indigenous breeds and that the infection may be severely debilitating and in many cases fatal. Observations of tsetse numbers and rainfall in the grazing area during the first year showed that there was a significant correlation between tsetse numbers and rainfall of the previous month. The increase in tsetse numbers, which occurred one month after substantial rainfall, was followed by an increase in the prevalence of trypanosomiasis in the animals. However, during the second year when rainfall was low there was no correlation between tsetse numbers and rainfall. It was concluded that the seasonal incidence of trypanosomiasis and the possible trypanotolerance of the indigenous breeds are important factors to be considered when initiating a small stock improvement programme for trypanosomiasis-endemic areas.  相似文献   

13.
Cooperia spp. have become the most prevalent parasites in United States cow/calf operations as observed in the USDA NAHMS (National Animal Health Monitoring System) Beef Cow/Calf survey in 2008. This is at least in part due to the widespread use of macrocyclic lactones that have recently been shown to have a reduced activity against these parasites. The effects of Cooperia spp. on cattle productivity are largely unknown. This study was conducted to assess their effect upon cattle housed under conditions found in American feedlots. Two hundred yearling calves (average weight 460 lb/209 kg) were acquired from northwestern Arkansas and northeastern Oklahoma and were vaccinated and dewormed upon arrival at the feedlot. Animals were comingled and preconditioned for approximately one month, and were fed a standard growing ration throughout the study. Calves were randomly divided into two groups (n=80, infected and control) and each group was further divided into two replicate pens (n=40). Calves from the two infected pens were orally inoculated with a gavage of 1 × 10(5) and 0.825 × 10(5) infective larvae of a recent isolate of Cooperia punctata on day 0 and 14, respectively, with the two control pens receiving a similar volume of tap water. Data collected included biweekly fecal egg counts, daily individual feed consumption and weight gain over the 60-day test period. The presence of C. punctata (>99% of recovered worms) was confirmed by necropsy and recovery from the small intestine on days 35 and 60 post infection (PI) in a subset of animals. Egg counts were positive by day 14 PI and remained at numbers similar to values seen in field studies. The control group gained weight 7.5% more rapidly (p=0.02) than infected animals (3.24 lb/1.47 kg per day vs. 3.0 lb/1.36 kg per day, respectively). The Cooperia-infected calves also consumed 1.5 lb (0.68 kg) less dry feed per day than the control animals (p=0.02). These data suggest that C. punctata has a deleterious effect on both appetite and nutrient uptake or utilization. At necropsy (days 35 and 60), the draining mesenteric lymph nodes of infected animals were increased in size and the small intestinal mucosa was thickened and covered with a thick layer of mucus in the infected animals. The most prominent histological changes in the Cooperia- infected animals included a moderate increase in the number of intraepithelial lymphocytes and globule leukocytes, as well as aggregates of eosinophils within the lower lamina propria. The only significant difference was an increase in the goblet cell density at day 60. Anthelmintic sensitivity/resistance of the Cooperia isolate used was determined by treatment of one pen of infected calves with a macrocyclic lactone and the other pen with a benzimidazole at the completion of the study. The macrocyclic lactone treatment (n=40) did not remove the parasites (FECRT=8.8%), while treatment with a benzimidazole was very effective (FECRT=98.1%). This study demonstrated that C. punctata has a significant effect on cattle productivity, both reduced weight gain and decreased feed intake compared to controls.  相似文献   

14.
After the diagnosis sarcoptic mange in four alpaca's (Lama pacos) we have tried to control this infection. Despite three treatments with doramectin, three with ivermectin, four with amitraz and two with diazinon we were unable to get the animals free of Sarcoptes mites and their condition deteriorated. One animal died six month after the first treatment. The three remaining animals were euthanized one month thereafter.  相似文献   

15.
The effective application of targeted selective treatment (TST) against gastro-intestinal nematodes depends on the accurate identification of those animals in need of anthelmintic treatment. Finding cost and labour effective measures to identify such animals is paramount. This study tested the efficacy of three indicators on lambs in a farm in Eastern Algeria: anaemia score (FAMACHA(?)), diarrhoea score (DISCO) and weight gain. These were contrasted against traditional parasitological infection measures (nematode eggs per gram of faeces: EPG). Thirty lambs were used in the study; every second month they were sampled (FAMACHA(?), faecal samples for EPG and DISCO, weight gains) and two of the original 30 lambs were necropsied for adult worm counts. The main gastro-intestinal nematodes were Teladorsagia circumcincta, Marshallagia marshalli, Nematodirus helvetianus, Trichostrongylus vitrinus, and Haemonchus contortus. DISCO proved to be the most effective indicator correctly identifying 80% of the sheep in need of treatment. This was followed by FAMACHA(?) with a 50% accuracy level and finally weight gains, which were not found to be a useful indicator at all.  相似文献   

16.
To evaluate the effect of different age of castration on live and slaughtering performances in Piemontese males a study was carried out on 24 cattle divided in 3 groups: EC—early castrated (5th month of age), LC—late castrated (13th month) and IM—intact males, reared under the same environmental condition until the same fattening degree, then slaughtered at 18 month of age. The animals were fed at the same energy and protein level. Live weight was recorded monthly and 18 linear body measurements were recorded at 18th month of age. Live performances and slaughtering data were recorded or calculated. Differences were found in live weight (higher in IM than EC and LC; P < 0.01), buttock girth, chest girth (both higher in IM than EC; P < 0.05) and shin girth (higher in IM and LC than EC; P < 0.05). The average daily weight gain was higher in IM compared to EC and LC (P < 0.01). The carcass weight was higher in IM than EC and LC (P < 0.01). Little differences were found between EC, LC and IM in some anatomical parts weights. No differences were pointed out in the dressing percentage. Castration of Piemontese bulls at 13th month of age do not improve live and slaughtering performances compared to animals castrated at 5 month of age, even if the LC linear body measurements are more similar to the IM than EC.  相似文献   

17.
The aim was to compare the effects of two production systems on performance, carcass traits and physical‐mechanical characteristics of leather from Beefalo‐Nellore steers and heifers and to determine if the response to the production system was similar for both genders. A total of 40 Beefalo‐Nellore cattle, 20 steers and 20 heifers, were evaluated. Animals were divided into two production systems: slaughtered at 15 (intensive system) or 26 (extensive system) months of age. In the intensive system, all animals received a ration containing 600 g/kg corn silage and 400 g/kg concentrate. In the extensive system, animals were kept on a pasture predominantly based on Brachiaria sp. and supplemented with 2 kg/day concentrate. In the intensive system, there was no difference in slaughter weight (470 kg body weight) between steers and heifers but steers in the extensive system had greater slaughter weight than heifers (463 and 428 kg body weight, respectively). Leather weight was higher for animals in the intensive than extensive system but there was no difference in leather weight once excess fat was removed. Leather quality from Beefalo‐Nellore cattle slaughtered at 15 or 26 months of age is similar although carcass yield is higher for cattle slaughtered at a younger age.  相似文献   

18.
Twenty‐four male weaned piglets assigned to four diets containing 5.0, 10.0, 15.0 and 0.2 mg fumonisin B1 (FB1) /kg as diets 1, 2, 3 and control diet, respectively, were used to study the effect of dietary FB1 on growth and puberty attainment in pigs in a 6‐month feeding trial. Lower feed intake during 0–4 months and a non‐significant (p > 0.05) but FB1 concentration‐dependent decrease in live and DWGs in animals fed FB1‐contaminated diets was observed at the end of the pubertal phase. The daily and the final live weight gains of animals fed diet 3 were 75.8% and 90.6%, respectively, of the control values. The mean ages at puberty by boars on diets 2 and 3 were significantly (p < 0.05) higher than those for animals on the control and diet 1. The animals on diet 3 attained puberty when mean live weight was 60.1 kg, some 30.3 days after the controls attained puberty, at 156.3 days, when the mean live weight was 46.9 kg. This study revealed that dietary FB1 delays sexual maturity in growing pigs. Male weanling pigs for breeding should not be exposed to dietary FB1 higher than 5 mg/kg for optimum growth and reproductive performance.  相似文献   

19.
The relationship between estrogen receptor (ESR) genotype and reproductive traits in a population of Yorkshire, Large White, and crossbred animals was studied. Reproductive tract and litter data were analyzed for associations with ESR genotype, parity, and breed. Forty-six Yorkshire, 31 Large White, and 70 crossbred females from the above population were mated to Hampshire boars and slaughtered at 75 d of gestation. Data collected included ovulation rate, uterine horn length, number of fetuses, fetal weight, uterine weight, number of mummies, fetal sex, fetal placement, fetal survival, and fetal space. Data were analyzed using a model that included the fixed effects of ESR genotype, breed, parity, and all significant two-way interactions. Litter data representing 212 litter records were analyzed in a model that included the fixed effects of ESR genotype of dam, parity, farrowing month, dam breed, sire breed, and all significant two-way interactions. The ESR genotype was significantly associated with the total litter weight of piglets born and total litter weight of piglets born alive. Dams with the AA genotype had significantly (P = 0.04) heavier litters at birth (14.44 +/- 0.36 kg) than dams with the BB genotype (13.43 +/- 0.47 kg). Ovulation rate was significantly (P < 0.05) different between animals of parity 1 (17.22 +/- 0.41) and parity > or = 3 (19.92 +/- 0.85). Significant breed effects were observed for fetal weight, with purebred Large White animals having a greater fetal weight per horn (3,909 +/- 114 g) than purebred Yorkshire animals (3,553 +/- 92 g). Notable, but nonsignificant, trends with respect to ESR genotype were also observed for number of piglets alive at weaning and total litter weight at weaning. The ESR gene is positively associated with several previously uninvestigated reproductive traits.  相似文献   

20.
The use of medium‐chain triglycerides (MCTs) has been studied for years in an attempt to elucidate their effects in food intake and body weight in animals. The aim of this study was to determine whether there is evidence that the use of MCT reduces consumption and body weight gain in rats, a species chosen as it has been widely used as an animal model in different surveys. A search of scientific work was performed in November 2011 on two bases: ‘Web of Science’ and ‘PubMed’. The terms sample size and homogeneity, randomisation, food consumption and weight gain, body composition, enzyme activity and hormonal activity in rats were used as selection criteria. Thirteen papers were selected after the refinement of the research. Twelve studies measured weight gain and among these, seven detected a decrease in weight gain and five found no differences. Twelve papers also measured food intake and among these, four detected a decrease in consumption, one detected an increase and seven found no differences. Based on established criteria for the ranking of scientific papers, it is concluded that there is strong evidence that MCTs can effectively reduce the consumption and subsequent weight gain of animals. However, in the long term, there may not be differences in results depending on the phenotypic adaptation of animals to a new metabolic condition.  相似文献   

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