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1.
This paper describes a hypothesis on the origin of the members of the recently established adenovirus genus, Atadenovirus, invading cattle, sheep, deer, duck and poultry. Comparison of the phylogenetic trees of adenoviruses and their hosts suggests a very ancient but common origin for the atadenoviruses. The surprisingly large difference between these virus types and other adenoviruses infecting the same host can be easily understood by assuming their separate evolution in different hosts (e.g., in reptiles versus a coevolution with mammals and birds, respectively) followed by a later host switch. 相似文献
3.
The present study was carried out in the northwestern region of S?o Paulo State, Brazil, to determine the anthelmintic resistance status in cattle naturally infected with gastrointestinal nematodes. The anthelmintics tested were levamisole phosphate (Ripercol, Fort Dodge), albendazole sulphoxide (Ricobendazole, Fort Dodge), ivermectin (Ivomec, Merial) and moxidectin (Cydectin, Fort Dodge), administered at the doses recommended by the manufacturers. From April 2002 to May 2004, 25 cattle farms were evaluated. On each farm, steers were divided into treatment and control (not treated) groups based on fecal egg counts (FEC). Between 7 and 10 days after the anthelmintics administration, fecal samples were collected from each animal for post-treatment FEC. Fecal cultures from each group were also prepared for larval identification. After treatment, mean FEC reduction (FECR) in treatment groups (compared with control groups) was assessed on each farm. FECR was lower than 90% on 23 farms after ivermectin treatment. On 19 farms, FECR of 100% was recorded following moxidectin treatment; on the remaining 6, FECR ranged from 90% to 97.2%. After albendazole treatment, FECR was higher than 90% on 20 farms and ranged from 47.4% to 84.6% on other 5. After levamisole treatment, FECR was higher than 90% on 23 farms and equal to 47.4% and 73.7% on other 2 farms. Results indicated the presence of resistant Cooperia spp. and Haemonchus spp., especially to ivermectin; on some farms, resistance to albendazole and levamisole was also observed. 相似文献
4.
1. Behavioural development in groups of 8 pullets kept in pens with litter floors, and fed on either mash or pellets, was studied from 0 to 10 weeks in a White Leghorn X broiler (F2) hybrid line (experiment 1) and from 0 to 24 weeks in Hisex, White Leghorn and Brown Leghorn strains (experiment 2). The aim was to identify precursors of feather pecking and cannibalism. 2. Rates of body weight gain were consistently greater with pellets than with mash in both experiments. In experiment 2, the onset of lay was at 17 weeks of age in Hisex, 21 weeks in White Leghorns and 23 weeks in Brown Leghorns. 3. Persistent feather pecking, which was not seen in experiment 1, developed in 2 of 12 groups (one Hisex and one White Leghorn, both fed on pellets) in experiment 2, and was studied in detail at 23 and 24 weeks. The more damaging pecking in the Hisex group was followed by cannibalism in the same group. 4. Based on the (often inconsistent) effects of genetic strain, age and food form on behaviour diat were observed, a working hypothesis was constructed to account for the aetiology of feather pecking and cannibalism in situations where there is floor litter. 5. An age‐related decline in one or more foraging activities may coincide with increases in preening and non‐damaging pecking at other birds. Consumption of litter particles and moulted feathers may be reinforcing. Dustbathing may enhance the stimulus value of litter particles when they are contrasted against background plumage colour. This may direct pecking towards the backs of birds, where feathers as well as litter particles may be removed and eaten. Regular pecking and feather removal may lead eventually, after the onset of lay, to vent pecking and cannibalism. This sequence of events may be more likely in groups where activity levels are high. 相似文献
5.
The livestock industry produces a large amount of greenhouse gases (GHG) that cause global warming. A high percentage of GHG emissions are derived from cattle and has been suggested to be a factor in global warming. With the global increase in the consumption of livestock products, the number of farm animals has increased. In addition, the reduction in productivity and reproductive capacity of cattle has resulted in accelerated GHG emissions. In a high-temperature environment, the pregnancy rate decreases, leading to an increase in animals that do not contribute to production. Consequently, GHG emission per unit product increases, thereby accelerating global warming. To reduce this environmental impact, it is important to improve the breeding efficiency of cattle by the use of reproductive technology and, thus, reduce the number of non-productive animals. Thus, reproductive biology plays a major role in mitigating global warming related to the livestock industry. 相似文献
7.
1. Meat quality is affected by factors such as stress, genetic strain and activity and is determined in part by measures of pH, colour and tenderness. In conventional laying hen cages (CC), lack of physical space and inability to perform highly motivated behaviours leads to stress and inactivity. Furnished cages (FCs) permit expression of highly motivated behaviours, but typically house larger group sizes than CC, thereby contributing to social stress. The objective of this study was to evaluate the effects of CC and FC laying hen housing environments and strain differences on meat quality of 80–81-week-old birds. 2. Pectoralis major meat quality was assessed for two flocks of Shaver White (SH), Lohmann Lite (LL) and Lohmann Brown (LB) hens housed in either 5-hen CC or 40-hen FC. Between 80 and 81 weeks, muscle samples were collected from randomly selected hens and analysed for muscle pH, colour and shear force (SF) using established methods. 3. In both flocks, the combined treatment body weights (BWs) were higher for CC than FC hens and the combined strain BWs were higher for LB than LL and SH hens. Flock 1 LB had lower initial and ultimate pH than SH and LL, and greater pH decline than SH. Muscle redness (a*) was higher for CC SH than FC SH in both flocks. Muscle a* was higher for LL than SH and LB in Flock 1, and higher than SH in Flock 2. Housing differences in muscle SF were absent. In CC, SF was higher for SH than LL and LB in Flock 1, and higher than LB in Flock 2. 4. Lack of housing differences suggests that environmental stressors present in both housing systems similarly affected meat quality. Strain differences for muscle pH, a* and SF indicate increased stress experienced by SH and LL hens. The absence of Flock 2 strain differences is consistent with the cannibalism outbreak that occurred in this flock and most severely impacted LB hens. 相似文献
8.
Summary To identify a simple method for assessing the selenium demand in cattle, the relationship between selenium content in whole blood and the concentration of the selenium containing enzyme glutathion peroxidase (EC 1.11. 1.9; GSH‐Px) in red blood cells was studied. On six farms with suspected low soil selenium content, blood samples were collected from groups of calves, yearlings and adults at the end of the housing period and of the grazing period. The data obtained showed a highly significant correlation between the parameters mentioned: GSH‐Px (U/g Hb) = 3.261 * Se (μg/kg) ‐ 40.553. In growing animals there was a decline in Se supply with age, followed by a gradual recovery in heifers. This was most pronounced on some sandy soils and on peat soil. Seasonal effects could not be demonstrated. 相似文献
9.
ObjectivesTo determine the endotracheal tube cuff pressure produced with two inflation techniques, in two brands of endotracheal tube in cats. To determine the inspiratory pressure which produces an audible leak when the intracuff pressure is 30 cmH2O.Study designProspective, clinical, randomized study.AnimalsA total of 40 client-owned healthy adult cats.MethodsFollowing induction of anaesthesia, endotracheal intubation was performed with a Parker Flex-Tip PFLP (Parker; n = 20) or Flexicare VentiSeal (Flexicare; n = 20) endotracheal tube. For each cat, the endotracheal tube cuff was inflated using two methods, minimum occlusive volume (MOV) and pilot balloon palpation (PBP). Intracuff pressure was recorded. Cuff pressure was then set at 30 cmH2O and the pressure within the breathing system when a manual breath first caused an audible leak was measured.ResultsPBP pressure was lower for Parker (36 ± 13 cmH2O) compared with Flexicare (45 ± 13 cmH2O, p = 0.048). MOV pressure was not different between tube types (56 ± 28 versus 66 ± 25 cmH2O for Parker and Flexicare, respectively, p = 0.247). MOV produced a higher pressure than PBP for Parker (56 ± 28 versus 36 ± 13 cmH2O, p = 0.001) and Flexicare (66 ± 25 versus 45 ± 13 cmH2O, p = 0.007). When intracuff pressure was set at 30 cmH2O, 95% of cats did not develop an audible leak until the inspiratory pressure was greater than 10 and 12 cmH2O for Parker and Flexicare tubes, respectively.ConclusionsPBP produced lower cuff pressures than MOV, although both techniques produced a cuff pressure above that at which mucosal blood flow is believed to be restricted. A cuff pressure of 30 cmH2O may be sufficient to prevent audible leak in most cats if respiratory pressures are kept at 10–12 cmH2O or below.Clinical relevanceTo ensure a safe endotracheal tube cuff pressure, use of a specifically designed pressure gauge is recommended. 相似文献
10.
The aim of this study was to assess the distribution of runs of homozygosity (ROH) and autozygosity islands in the composite Montana Tropical ® beef cattle to explore hotspot regions which could better characterize the different biological types within the composite breed. Montana animals ( n = 1,436) were genotyped with the GGP-LD BeadChip (~30,000 markers). ROH was identified in every individual using the plink v1.90 software. Medium and long ROH prevailed in the genome, which accounted for approximately 74% of all ROH detected. On an average, 2.0% of the genome was within ROH, agreeing with the pedigree-based inbreeding coefficient. The Montana cattle with a higher proportion of productive breed types showed the highest number of autozygosity islands ( n = 17), followed by those with a higher proportion of breeds adapted to tropical environments ( n = 15). Enriched terms ( p < .05) associated with the immune and inflammatory response, homeostasis, reproduction, mineral absorption, and lipid metabolism were described within the autozygosity islands. In this regard, over-represented GO terms and KEGG pathways described in this population may play a key role in providing information to explore the genetic and biological mechanisms together with the genomic regions underlying each biological type that favoured their optimal performance ability in tropical and subtropical regions. 相似文献
11.
This study was conducted to determine the prevalence and characteristics of Johne’s disease (JD) lesions in Ugandan cattle slaughtered at two of the main abattoirs in Kampala. Ileocaecal junction and the associated lymph nodes of 1,022 cattle were examined for gross and microscopic lesions, followed by Ziehl Neelsen staining of the tissues bearing lesions. Confirmation of Mycobacterium avium subsp. paratuberculosis infection was done in some of the tissues using culture and IS900 PCR. The lesions were then described, characterised and tabulated. Characteristic Johne’s disease granulomas were found in 4.7% of the samples examined, derived from Zebu, Ankole longhorn, Friesian breeds of cattle and their crosses. Lesions were found both in the lymph nodes and ileocaecal junction mucosa. The lesions tended to be more severe in the lymph node than in the mucosa. There were also some unique and atypical lesions found in association with Johne’s disease granulomas. The diagnostic values of various gross lesions and criteria of lesion classifications and diagnosis are revisited and discussed based on the findings of this study. The prevalence of Johne’s disease lesions among slaughtered cattle in Kampala’s two abattoirs indicates that the disease is well established in the cattle population in the country. The diverse manifestations in lesions of JD need to be considered when making histological diagnosis in tissues where the disease is suspected. 相似文献
12.
A sporadic wasting syndrome affecting beef cattle herds parasitized by Eurytrema coelomaticum is described in the State of Paraná, southern Brazil. The disease was characterized by progressive weight loss, poor body condition despite plenty of good quality forage available, and death. Annual losses ranged from 1 to 3%. The clinical course of the disease varied from 2 to 10 months after the onset of the first clinical signs. At necropsy, one of the three distinct following patterns of lesions were observed: the pancreas was of normal size and color; small, shrunken, white and markedly and diffusely firm (fibrosis); or slightly enlarged and dark with a shriveled capsular surface. Myriads of leaf-shaped trematodes of the genus Eurytrema were packed inside multiple dilated ducts with thickened, whitish fibrous walls, or the flukes were embedded in the remaining pancreatic parenchyma. Microscopic findings included extensive loss of the pancreatic parenchyma with replacement fibrosis, intralesional flukes and eggs, and ductal hyperplasia. Inflammatory reaction varied from absent to severe with the presence of a granulomatous reaction around the trematode eggs. One affected animal had high plasma amylase concentration (1580U/L) suggesting exocrine pancreatic insufficiency. Glucose blood levels were not significantly increased. We suggest that diffuse and marked fibrosis of the pancreas induced by the presence of large amounts of pancreatic flukes is the cause of the sporadic cases of chronic wasting and death of cattle in this geographic area. 相似文献
13.
The effect of two forage neutral detergent fiber (NDF) levels (6 vs. 9%) and two forage sources (sorghum stover vs. alfalfa hay) on growth performance was evaluated in 20 feedlot lambs (17.45?±?2.75?kg) for a 60-d feeding-period. Final longissimus area and subcutaneous fat were measured by ultrasound. There were no treatment interactions. Lambs receiving sorghum stover had greater gain efficiency ( p?=?.04), estimated dietary net energy (NE; p?=?.04), longissimus area ( p?=?.02) and tended to greater average daily gain (ADG; p?=?.06) than lambs fed alfalfa hay. Lambs receiving 6% forage NDF had greater ADG ( p?=?.03), gain efficiency ( p?=?.03) and tendency toward for dietary NE ( p?=?.06) than those fed 9% forage NDF. Treatments did not influence subcutaneous fat. In conclusion, at equivalent forage NDF level, sorghum stover may be superior to alfalfa hay for feedlot lambs which may depress growth performance at 9% forage NDF in isocaloric diets including a 50:50 blend of whole and ground sorghum grain. 相似文献
14.
High reproductive performance is required for successful management of dairy farms. After calving, especially endometritis is one of the main reasons for reproductive failure. However, subclinical endometritis remains undetected in many cases and causes a high financial loss. To elucidate the cellular processes in the endometrium, the acquisition of the gene expression will provide helpful information. In the literature, numerous cytokines and enzymes were discussed to play important roles in preparing the endometrium for implantation. This review gives an overview about our present understanding of the functions of cyclooxygenases 1 and 2 (COX-1/COX-2), tumor necrosis factor alpha (TNFalpha), the inducible nitric oxide synthase (iNOS), haptoglobin as well as the interleukins 1 and 6 (IL-1/IL-6). Their role is not only to regulate certain physiological processes in the bovine reproductive tract, but to act also as inflammatory mediators in infectious diseases. A better understanding of cellular processes may help to improve identification and treatment of postpartum reproductive failure. 相似文献
15.
IntroductionHypertrophic cardiomyopathy (HCM) has a variable prognosis; left atrial size, presence of clinical signs and left ventricular systolic function have been shown to predict outcomes. Mitral annular plane systolic excursion (MAPSE) and tricuspid annular plane systolic excursion (TAPSE) assess longitudinal ventricular systolic function and are decreased in cats with HCM. The aim of the study was to ascertain whether MAPSE and TAPSE have prognostic value in HCM and if cats with pleural effusion have lower MAPSE and TAPSE than cats with pulmonary oedema.AnimalsOne hundred eighty-four client-owned cats diagnosed with HCM.MethodsThis is a retrospective study. Echocardiography was used to diagnose HCM (end-diastolic left ventricular wall thickness ≥ 6 mm) and to measure MAPSE and TAPSE. Survival information was obtained.ResultsNo multivariable model including MAPSE or TAPSE could be generated in this population. Cats with pleural effusion ± pulmonary oedema had lower MAPSE measured at the interventricular septum (MAPSE IVS) and TAPSE, compared with cats with pulmonary oedema only. MAPSE IVS was the only factor predicting pleural effusion on multivariable regression model.ConclusionsLower MAPSE and TAPSE were not independently associated with outcomes on multivariable analysis. Cats with pleural effusion ± pulmonary oedema had lower TAPSE and MAPSE IVS than cats with pulmonary oedema, and MAPSE IVS was the only predictive factor associated with the development of pleural effusion in this population. 相似文献
16.
This study was carried out to evaluate the blood profile and tissue expression of Anti-Müllerian hormone (AMH) as a biomarker for granulosa-theca cell tumors (GTCTs) in cattle. Five cases with unilateral ovarian GTCTs (GTCT group) were investigated in comparison to other groups of Japanese Black cows, which had either cystic ovarian disease (COD group, n=5), a functional corpus luteum on Days 9 to 11 of the estrous cycle (Day 0=estrus; CL group, n=13) or received superovulation treatment (SOT group, n=13). We used transrectal ultrasonography and measured plasma AMH, estradiol-17β (E(2)), progesterone (P(4)) and testosterone (T) levels. Moreover, GTCT tissues were collected and examined by immunohistochemical staining (IHC) for AMH. In the GTCT group, ultrasound images of GTCTs were variable and not definitive. However, the AMH level in the GTCT group (n=3, 58.1 ± 66.3 ng/ml) was significantly higher than in the COD, CL and SOT groups (0.1 ± 0.1 ng/ml for GTCT vs. COD, P<0.05; 0.2 ± 0.1 and 0.3 ± 0.2 ng/ml, respectively for GTCT vs. CL and SOT, P<0.01). The other hormonal levels in the GTCT group had no significant differences compared with the COD or SOT group. Neoplastic granulosa cells labeled with AMH antibody clearly demonstrated a variety of tissue patterns in all cases by IHC. To the best of our knowledge, this is the first study to investigate the blood profile and IHC of AMH in bovine GTCTs. Our findings indicate that AMH may be a novel biomarker to diagnose GTCTs in cattle. 相似文献
17.
Tropical Animal Health and Production - This study aimed to estimate the genetic parameters of milk (305-day milk yield (MY305)), growth (weaning weight (WW), yearling weight (YW), and weight at... 相似文献
18.
Summary A solid‐phase enzymeimmunoassay (EIA) was developed for progesterone, based on horse radish peroxidase as the enzyme‐label and Dasp ® (sheep anti‐rabbit Ig, covalently linked to cellulose) for separation of antibody‐bound and free hormone. The validity of the assay was substantiated in accordance with criteria for sensitivity, precision, accuracy and specificity; it is simple to perform and can be done in one day. Milk samples were taken on the day of A.I. (day 0) and on day 21 from 60 dairy cows which belonged to an artificial insemination (A.I.)station in the central part of Thailand. Conception rate (C. R.) after first A.I., as diagnosed by the milk‐progesterone test, was 31.7 per cent. Based on rectal exploration on day 84–93 and on ‘non‐return’ at 85 days, C. R. was 20.0 per cent and 23.3 per cent, respectively. All animals except one showed non‐luteal phase progesterone levels at the time of A.I. It is concluded that low C. R. in these cows is not due to inseminations during the luteal phase of the oestrous cycle. 相似文献
19.
The first cases of circovirus infections in pigeons were documented less than 25 years ago. Since then, circovirus infections have been reported on nearly all continents. The specificity of pigeon breeding defies biosecurity principles, which could be the reason for the high prevalence of PiCV infections. PiCV infections in pigeons lead to atrophy of immune system organs and lymphocyte apoptosis. Infected birds could be more susceptible to infections of the respiratory and digestive tract. PiCV has been associated with the young pigeon disease syndrome (YPDS). PiCVs are characterized by high levels of genetic diversity due to frequent point mutations, recombination processes in the PiCV genome and positive selection. Genetic recombinations and positive selection play the key role in the evolution of PiCV. A protocol for culturing PiCV under laboratory conditions has not yet been developed, and traditional vaccines against the infection are not available. Recombinant capsid proteins for detecting anti-PiCV antibodies have been obtained, and these antigens can be used in the production of diagnostic tests and subunit vaccines against PiCV infections. However, YPDS has complex etiology, and it remains unknown whether immunization against PiCV alone will contribute to effective control of YPDS. 相似文献
20.
Oesophageal fistulated steers were used to sample herbage daily during periods of occupation on veld in good and moderate condition. Forage quality was assessed in terms of in vitro dry matter digestibility and digestible crude protein. The quality of herbage ingested remained fairly constant as forage availability declined during periods of occupation, even when swards were grazed very severely. Digestibility declined somewhat from spring through to winter, but digestible crude protein content in the diet was unaffected by time of year. The quality of forage ingested during winter was nevertheless still high, even after a full growing season's rest. It was sufficient for growing steers to gain 0,75 kg livemass per day. Trends were similar on both veld condition types. It was concluded that, in semi‐arid grassveld of the eastern Cape, forage availability is likely to have a greater influence on animal performance than forage quality. 相似文献
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