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1.
The purpose of the present study was to study the soil–plant–animal continuum in subtropical hilly areas. Soil (n?=?96), fodder (n?=?96), and blood serum samples from dairy cattle (n?=?120) were collected from eight districts of Mizoram, a hilly state in India. The samples were digested using diacid mixture (HNO3:HClO4; 10:4) and analyzed for macro (Ca, P, Mg, Na, and K) and micro (Cu, Co, Mn, Fe, and Zn) mineral concentrations. The macro and micro mineral concentrations varied among the different districts. The correlation values between fodder and cattle were significant for all the minerals studied except for P and K. The correlation value between fodder and cattle was highly significant (P?<?0.01) for Ca (0.878), Mg (0.88), Cu (0.885), and Zn (0.928). However, such correlations were not observed between the mineral levels in cattle and mineral levels in soil except for Ca (0.782). Equations developed in the present study for prediction of Ca (R 2?=?0.797), Mg (R 2?=?0.777), Zn (R 2?=?0.937), Fe (R 2?=?0.861), and Cu (R 2?=?0.794) had significant R 2 values. Further, it is inferred that dairy cattle reared under smallholder production system were deficient in most of the minerals and supplementation of required minerals is essential for optimum production.  相似文献   

2.
Early detection of Johne’s disease (JD) caused by Mycobacterium avium subspecies paratuberculosis (MAP) is essential to reduce transmission; consequently, new diagnostic techniques and approaches to detect MAP or markers of early MAP infection are being explored. The objective was to identify biomarkers associated with MAP infection at 6 and 9 months after oral inoculation. Therefore, gene expression analysis was done using whole blood cells obtained from MAP-infected calves. All MAP-inoculated calves had a cell-mediated immune response (IFN-γ) to Johnin PPD specific antigens, and 60% had an antibody response to MAP antigens. Gene expression analysis at 6 months after inoculation revealed downregulation of chemoattractants, namely neutrophil beta-defensin-9 like peptide (BNBD9-Like), S100 calcium binding protein A9 (s100A9) and G protein coupled receptor 77 (GPR77) or C5a anaphylatoxin chemotactic receptor (C5a2). Furthermore, BOLA/MHC-1 intracellular antigen presentation gene was downregulated 9 months after inoculation. In parallel, qPCR experiments to evaluate the robustness of some differentially expressed genes revealed consistent downregulation of BOLA/MHC-I, BNBD9-Like and upregulation of CD46 at 3, 6, 9, 12, and 15 months after inoculation. In conclusion, measuring the expression of these genes has potential for implementation in a diagnostic tool for the early detection of MAP infection.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-014-0096-5) contains supplementary material, which is available to authorized users.  相似文献   

3.
Risk factors associated with failure of passive transfer of immunity (FPT) were evaluated among newborn beef calves in Québec. Physical examination was performed on calves born of a normal calving and blood samples were collected for determination of health status and measurement of serum concentration of immunoglobulin (Ig) G1. Of 225 calves, from 45 herds, 19% showed FPT (serum IgG1 concentration < 10.0 g/L). Calves born in a stanchion-stall were more likely to show FPT (OR: 10.2). Calves bottle-fed colostrum were less at risk for FPT (OR: 0.06). Calf gender, month of birth, dam parity, and dam body condition score were not associated with FPT. No association was detected between FPT and health status. Special care should be given to calves born from cows in a stanchion-stall to ensure adequate colostrum intake. Failure of passive transfer of immunity should be considered with other risk factors when investigating morbidity.  相似文献   

4.
Daily milk yield of Ogaden cattle was estimated from milk suckled by 269 calves born and maintained between 1994 and 2004 at Haramaya University Beef Farm, Ethiopia. The weigh–suckle–weigh method and the growth of calves were used to estimate the yield. Mean predicted daily milk yield of the breed based on the weigh–suckle–weigh method was 4.39 ± 0.03 kg day−1. Daily milk yield estimated from the growth of calves up to 3 months of age was 4.59 ± 1.43 kg day−1. The milk yield was significantly affected by seasons of calving (p < 0.001), parities of the dams (p < 0.05), weeks of lactation (p < 0.001) and birth weights of calves (p < 0.05). A relatively higher milk yield was observed from cows calved during the long rain season. A higher milk yield was produced by cows in fifth parity. Heavier calves at birth suckled more milk than lighter calves. Daily milk yield was significantly higher in 3–6 weeks of lactation. The result of this study indicated that the milk yield produced by Ogaden breed was relatively higher than the yield of some Zebu breed measured by partial suckling system in Ethiopia and was comparable to the yield from Zebu cattle in the tropics estimated by the same method.  相似文献   

5.
After a milk meal, bucket-fed calves show non-nutritive oral activities, including cross-sucking, and this can discourage producers from rearing them in groups. Sucking is known to induce a quiet state in humans and rats. We examined if nutritive sucking affects non-nutritive oral activities in calves, if it reduces arousal (assessed through behavior and cardiac activity), and if sucking a dry teat can compensate for the lack of nutritive sucking. In Exp. 1, the behavior and the cardiac activity of individually housed calves fed milk from a bucket were compared to those of calves fed milk through a teat. During the meal, the heart rate of bucket-fed calves was higher than that of teat-fed calves (P < 0.0001). After the meal, only bucket-fed calves displayed bar sucking. Compared to the teat-fed calves, they spent more time licking their pen or their neighbor (P < 0.001 and P < 0.05), their heart rate was less variable (P < 0.01), and they lay down with the head unsupported by the neck less quickly (latency to lie down: 51 min vs 42 min, P < 0.05). In Exp. 2, individually-housed bucket-fed and teat-fed calves were observed with or without access to a non-nutritive teat after the meal. Bucket-fed calves sucked the dry teat for longer than teat-fed calves (P < 0.001). In bucket-fed calves, access to the dry teat reduced the time spent nibbling (P < 0.01) and tended to shorten the latency to lie down (P < 0.10). In Exp. 3, group-housed bucket-fed calves were compared with group-housed calves fed with an automatic teat feeder system. Bucket-fed calves spent more time nibbling at 1 mo, but at 3 mo they spent less time nibbling and cross-sucking; they drank more milk and put on more weight. We conclude that, for calves housed individually, teat-feeding reduces non-nutritive oral activities after the meal and induces a calmer state than bucket-feeding. Providing calves with a dry teat partly compensates for the lack of nutritive sucking. For calves housed in groups, the use of an automatic teat feeder may not reduce calves' motivation for sucking. No improvement of growth was observed with teat-feeding either with a teat-bucket or with an automatic feeder.  相似文献   

6.
1. An experiment was carried out with 6‐d old male broiler chicks in an attempt to understand better the effect of age on dietary AMEn of high protein‐low energy (HPLE) and low protein‐high energy (LPHE) diets which are used in the determination of the AMEn content of grains when substituted for the entire diet. The experiment was carried out in a split‐plot design in which the effects of 2 diets (HPLE‐reference and LPHE‐test, containing maize) on food intake, faecal excretion, dietary AMEn and the utilisation of the nutrients were evaluated in 3 age periods (A = 11–13, B = 15–17 and C = 20–22 d of age).

2. Chicks fed on the HPLE diet consumed significantly less food than those fed on the LPHE diet during periods A and B, but not in G. They also produced a significantly larger amount of droppings during periods B and C. Food‐to‐droppings ratio, which was consistently and significantly lower in chicks fed on the HPLE diet, decreased markedly in period C only in these birds.

3. Absolute and relative retention (RR) of dry matter (DM) and starch, and RR of nitrogen (N) from birds fed on the HPLE diet, were consistently and significandy lower than from those fed on the LPHE diet, but fat retention (absolute and relative) was higher. RR of DM and of N in period C was significantly lower than in periods A and B, while RR of fat and of starch was not affected by age. The effect of age on RR of N was observed only with the HPLE diet.

4. AMEn of the HPLE diet, but not of the LPHE diet, in period C was significandy lower than in periods A and B, resulting in a significant interaction between age and diet and a general reduction with age. The calculated AMEn contents of the maize in periods A and B were essentially the same (14.91 and 14.85 MJ/kg, respectively), and lower than in period C (15.28 MJ/kg). It is concluded, therefore, that because of its effect on AMEn of the HPLE reference diet in chicks older than 17 d, bird age is of considerable importance in the determination of AMEn in grains when substituted for the entire diet.  相似文献   


7.
Colloidal gold immunochromatographic was uesd for the determination of β-lactams and tetracyclines in milk. Tetracyclines hapten was obtained by chemical synthesis. Immunogen and envelope antigen were prepared by cephalosporins and tetracyclines hapten coupled to carrier protein. Monoclonal antibodies were obtained by immunogen immunizing mice. A rapid and simple colloidal gold immunochromatographic assay was established for the determination of β-lactams and tetracyclines in milk. 12 kinds of β-lactams and 4 kinds of tetracyclines were detected at the same time by the strip. The milk sample could be used to be detected without dilution. The detection time could be 3 to 5 min. The method could be efficiently used for mass samples screening in primary laboratory.  相似文献   

8.
The number of -motoneurons in the spinal cord segments C6 to Th2 of five calves with Arthrogryposis Multiplex Congenita (AMC) and of five normal calves was compared. A statistically highly significant reduction in the number of -motoneurons in segment C6 was observed in the affected calves. Two hypotheses to explain the effect of these findings were proposed. Firstly, it was thought that AMC may result from paresis of some muscles of the girdle, shoulder and elbow. Secondly, it was postulated that the decrease in the number of -motoneurons in C6 may have induced a radial nerve dysfunction resulting in AMC.This work was supported by the IWONL, Brussels, Belgium.  相似文献   

9.
Summary

A potent ß‐agonist (clenbuterol) was administered perorally to young calves for 50 days. After this period the animals were slaughtered and ß‐adrenoceptor density, ligand affinity, and basal and stimulated adenylate cyclase activities were studied in smooth muscle and epithelium of the trachea. Although the density of lung ß‐adrenoceptors was down regulated by clenbuterol, cAMP production remained constant (epithelium) or even increased (smooth muscle). Therefore desensitization of ß‐adrenoceptors in the trachea was not observed. This might be a reason for the effectiveness of long‐term treatment with ß‐agonists.  相似文献   

10.
11.
A cross-sectional questionnaire-based study was conducted to assess milk producers’ awareness of milk-borne zoonoses in selected smallholder and commercial dairy farms of Zimbabwe. The questionnaire was designed to obtain information on dairy breeds, milk production, dairy farmers’ knowledge and awareness of zoonoses with particular emphasis on milk-borne zoonoses and farmers’ behavioural practices that may lead to increased risk of milk-borne zoonoses transmission. A total of 119 dairy farmers were interviewed, and 41.5% were aware of milk-borne zoonoses with a significantly (P < 0.01) higher percentage of commercial dairy farmers (65.0%) being aware compared to smallholder dairy farmers (36.7%). The behavioural practices of dairy farmers observed to increase the risk of milk-borne zoonoses transmission were; consumption of raw milk (68.1%), sale of raw milk to the local public (25.2%), lack of cooling facilities by smallholder farmers (98%), and no routine testing (84.9%) and medical check-ups (89.1%) for milk-borne zoonoses. General hygienic and disease control practices need to be integrated in the milk production process particularly at the smallholder level. Awareness, teaching and training programmes for smallholder dairy farmers can improve disease control in animals and reduce the public health risk of milk-borne zoonoses.  相似文献   

12.
Tropical Animal Health and Production - We evaluated the relationship between the temperature–humidity index (THI) and health and growth performance in Japanese black calves in Japan. Data...  相似文献   

13.
Congenital chondrodystrophy of unknown origin (CCUO) has been reported in beef cattle worldwide. A trace mineral deficiency in pregnant dams has been suggested as causing the deformities seen in CCUO calves. An extended outbreak of CCUO in Australia between 2002 and 2009 provided an opportunity to examine the pattern of trace mineral status in gestating cows and the effect of parenteral trace mineral supplementation on a herd at risk of CCUO calves. A property with a strong history of CCUO was identified from a previous case–control study. A randomly selected sample of multiparous (8 to 10 years old) Angus and Angus cross cows (= 20) was assigned to control (no injection) or supplement group given three injections at the recommended dose rate of chelated mineral supplement (Mn, Zn, Cu and Se) at 6‐week intervals in mid‐ to late gestation. Liver biopsies were performed to measure liver Mn, Zn, Cu and Fe at each injection time and 1 month post‐calving. Pasture samples were also collected for analysis. Supplemented cows had higher liver Cu levels compared to control cows (p < 0.001), but there was no difference between supplement and control cows for liver Zn, Fe or Mn. Liver Cu (p < 0.001), Fe (p < 0.001) and Zn (p < 0.001) fell during gestation and liver Mn increased after calving (p < 0.001). Three cows from the control group and two from the supplement group had liver zinc levels below the normal values at the end of the trial. Two cows from the control group and one from the treatment group gave birth to cows with signs of CCUO including superior brachygnathia. All cows except one from the control group had rough dry coats with excessive dander. The role of trace mineral status in the birth of CCUO calves, especially the role of zinc deficiency, requires further investigation.  相似文献   

14.
The total muscarinic (M1 + M2 + M3) and -adrenergic receptors in the tracheal smooth muscle of conventional and double-muscled calves were identified and characterized with the non-specific antagonists [3H]quinuclidinyl benzilate ([3H]QNB) and [3H]dihydroalprenolol ([3H]DHA) respectively.Although the quantity of -adrenoceptors in double-muscled calves was 25% lower (p<0.05) than in conventional calves (B max=327±89 fmol/mg protein), adenylate cyclase assays indicated that the basal adenylate cyclase activity and the (–)-isopropylnoradrenaline (ISO)- and sodium fluoride (NaF)-stimulated values were not significantly different between these calves. However, the density of muscarinic receptors in double-muscled calves was 40% higher (p<0.01) than in conventional calves (B max=2955±625 fmol/mg protein). Subtypes of muscarinic receptors were studied with [3H]telenzepine (M1-receptors), [3H]AF-DX 384 (M2-receptors) and [3H]4DAMP (M1 and M3-receptors). It was found that in both double-muscled and conventional calves about 40% of the receptors were of the M3-subtype, the remaining 60% being M2-receptors.From these results, it is suggested that inflammation of the respiratory tract in double-muscled calves may be complicated by an imbalance between the cholinergic bronchoconstrictor and the -adrenergic bronchodilator components of the autonomic nervous system.  相似文献   

15.
Summary

During the course of experimental single infection with Fasciola hepatica in calves, the origin of the increased concentration of gamma‐glutamyl transpeptidase (γ‐GT) found to be present in the serum during the biliary stage of the disease, was studied.

The enzyme originates from the liver after flukes have caused intermittent and selective cholestasis in the bile‐duct system. The enzyme which normally is present in the bile ducts can under these circumstances enter the surrounding interstitial tissues through broken‐up junctions of the bile drainage system or be added to these from proliferating bile‐ductule epithelium. The multiplication of bile‐ductule cells can be looked upon as a neogenesis of cholangioles, which becomes essential when newly formed perilobular connective tissues prevent restoration of the anatomical connections of the bile capillaries with the biliary tree. The connective tissue growth is induced by bile fluid. An initially regional perilobular fibrosis is eventually distributed diffusely through the liver by migration of flukes.

The continued and extending fibrosis is due to the constant recurrence of intermittent and selective cholestasis. The transient occlusions of branches of the bile ducts are very likely to be attributable to persistent cholangitis. The growth of connective tissues has a considerable effect on the gain in weight of the liver.  相似文献   

16.
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18.
Data on breeding practices and traits of economic importance for the indigenous chicken (IC) were collected through personal interviews using structured questionnaires and direct observations of chicken management practices. The study was conducted from November 2015 to January 2016 in Rwamagana, Rulindo, Ruhango, Kicukiro and Muhanga districts of Rwanda. Data were collected and analysed through computation of indices, which represented a weighted average of all rankings of a specific trait. Spearman’s non-parametric rank correlation was calculated for ranking of traits of economic importance to indicate the directional effects. The results on chicken ecotypes and their attributes showed that prolificacy, mature weight, disease tolerance, egg number and heat tolerance were highly preferred. The dwarf ecotype was most abundantly reared (38.84%) and considered to be significantly smaller and to have poorer growth rate, but to have better prolificacy than other indigenous chicken ecotypes. Selection of breeding cock and hen was based on disease tolerance, body weight at sexual maturity, body size and growth rate. In addition, for hen, mothering ability and egg fertility (Fer) were considered. Indices for the traits perceived by farmers as of primary economic importance were egg yield (0.093), disease tolerance (0.091), high growth rate (0.089), prolificacy (0.088), high body weight (0.087) and egg fertility (0.083). The most important traits considered by the marketers were body weight (BW), disease tolerance (Dtol), plumage colour (Pcol), egg yolk colour (EYC), meat quality (MQ), growth rate (GR) and egg yield (EY) whereas for consumers, meat quality, egg yolk colour, egg yield, body weight and growth rate were considered. Among traits perceived as important by farmers, a positive and significant correlation was found between BW and GR and Fer. Correlation was moderate for BW and prolificacy, drought tolerance (Drtol), Dtol and EYC. BW was negatively correlated with temperament (Temp), heat tolerance, Pcol and egg shell colour (ESC). Regarding marketers and consumers’ preference rank correlation, positive and significant correlation was between BW and GR and MQ. As such, appropriate ecotypes (indigenous chicken) which have these characteristics need to be identified and utilised more based on their performance and adaption to the environment conditions to ensure efficient IC production.  相似文献   

19.
Taking into account the beneficial effects of antioxidants in reducing morbidity and mortality in calves, the aim of this study was to evaluate the effects of vitamins E and C on the development of the inflammation process and on selected defence mechanisms against infections induced by M. haemolytica.The study was carried out on 30 Simmentaler calves weighing about 100 kg, which received s.c.vitamin E (750 UI) or vitamin C (2.5 g/calf). In leukocytes obtained from the calves, sensitivity to the cytotoxic effect of M. haemolytica Lkt was evaluated using the MTT assay, expression of β2-integrin receptors on leukocyte surfaces was assessed, and metabolic activity was measured by the nitrotetrazolium blue test (NBT). Concentration of haptoglobin (Hp) and serum amyloid A (SAA) was estimated in the sera obtained.Analysis of the intracellular metabolism of the leukocytes showed no statistically significant differences compared to the control. A difference (p ≤ 0.05) was observed in the sensitivity of the leukocytes to the cytotoxic effect of Lkt in comparison with the control group. No differences were found in the percentage of cells sensitive to Lkt between the group given vitamin E and the calves which received vitamin C. The percentage of expression of β2-integrin receptors reached its lowest values on leukocytes isolated from the calves given vitamin E. The correlation between expression of β2-integrins and sensitivity of leukocytes to Lkt showed the greatest correlation on day 14 in calves given vitamin E, and on day 21 in calves given vitamin C.Analysis of Hp concentration in the sera showed no differences between the two groups of calves tested, but revealed differences (p ≤ 0.05) in absorbance values compared to the control on particular days of experiment. SAA concentration in the sera of calves from the group that received vitamin E was similar to that of the control on days 14 and 21 of the experiment. On days 3 and 7 of the experiment a significant (p ≤ 0.05) decrease was observed in SAA in the sera obtained from calves from the group given vitamin E compared to the control and the group given vitamin C.  相似文献   

20.
There are very few resistance records on cattle nematodes. South American successive records have been increasing rapidly since the year 2000. In Argentina, increasing dissatisfaction based on the exclusive use of macrocyclic lactones has prompted the use of benzimidazoles in the Pampean region. The studied farm is located in the Argentina humid Pampas and had apparently poor results after anthelmintic treatments. Evaluation of resistance was firstly based on faecal egg reduction after treatment in November 2001 and June 2002 and was complemented with worm counts obtained by necropsy in June 2002. The study reports that the reduction of faecal egg excretion after benzimidazole (reduction 31-79%) or ivermectin treatments (76-97%) in November 2001 was insufficient and these poor results were confirmed in June 2002 (benzimidazoles (65-89%) and ivermectin (47-77%)). Several methods for evaluating faecal egg count reduction were performed and yielded different results. A new method based on the estimated faecal egg counts (corrected from the initial faecal egg counts and animal type using a general linear model) was used and gave higher flexibility in the interpretation of putative resistance to anthelmintics. From necropsy results, it could be concluded that Cooperia oncophora was resistant to avermectins and benzimidazoles and that Cooperia punctata, Ostertagia ostertagi and Haemonchus placei were resistant to benzimidazoles. This case of multispecies and multidrug resistance is probably not unique and could reflect the emergence of resistances in Argentina. This emergence is probably due to the intensive use of anthelmintics, the absence of refugia, and the frequent circulation of infected cattle.  相似文献   

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