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1.

Background

This study was performed to determine the prevalence of ulcers in the gastric squamous and glandular mucosa in Polish pleasure horses.

Study design

Medical records from gastroscopic examinations of 108 pleasure horses of different breeds were reviewed. The study population consisted of two groups; group I (n = 48) with horses that expressed mild clinical signs of gastric ulcer syndrome (EGUS) including poor appetite, slight weight loss or poor body condition, and group II (n = 60) with horses that had no signs of gastrointestinal problems. The age range was 4–10 years, including 5 males, 34 castrated males (geldings) and 69 mares. The prevalence, distribution and severity of gastric ulcers were recorded. Lesions involving the squamous mucosa and the glandular mucosa of the antrum and pylorus were graded and compared between groups.

Results

Significant difference was found in the presence and severity of gastric ulcers between the two groups of horses. The overall prevalence of gastric ulcers in the first group of horses (n = 48) was 59% while in the group of clinically healthy horses (n = 60) the prevalence of gastric lesion was 40% (P = 0.004). Almost 19% of horses from group I had between 6–10 lesions (EGUS score III) and nearly 19% had either >10 localized lesions or very large diffuse lesions (EGUS number score IV). The number of ulcerations in affected horses were significantly lower in group II compared to group I (P = 0.016) as 10% of horses had 6–10 lesions (EGUS number score III) and nearly 14% had either >10 localized lesions or very large diffuse lesions (EGUS number score IV). Gastroscopy revealed that nearly 32% of horses from the second group had an ulceration EGUS score ≥ II.

Discussion and conclusions

This study confirms that gastric ulcerations can be prevalent in apparently clinically normal pleasure horses and a complete gastroscopic examination including the examination of the pylorus is advisable to evaluate this syndrome.  相似文献   

2.

Background

Canine generalized demodicosis associated with hyperadrenocorticism is often problematic and might be intractable. The aim of this study was to report the efficacy of a weekly application of spot-on moxidectin/imidacloprid in dogs with hyperadrenocorticism and secondary generalized demodicosis.

Methods

Dogs with hyperadrenocorticism and secondary generalized demodicosis were included. The condition of hyperadrenocorticism was treated and stabilized with trilostane before and throughout the study period in all dogs.

Results

Average total live adult mite counts before treatment and after four, eight and 12 weeks of spot-on moxidectin/imidacloprid (2.5/10 mg/kg) applications were 20.1 ± 6.3 (range, 13–33), 0.5 ± 0.7 (range, 0–2; 6/11 were negative), 0.2 ± 0.4 (range, 0–1; 9/11 were negative), 0.2 ± 0.4 (range, 0–1; 9/11 were negative) and 0.1 ± 0.3 (range, 0–1; 10/11 were negative) respectively; this difference was significant (P < 0.001). Ten of 11 dogs (90.1%) achieved clinical remission, as demonstrated by the absence of demodectic mites at any life stage at monthly scrapings for eight consecutive weeks, and maintained remission throughout the 12-month follow-up period.

Conclusion

The weekly application of spot-on moxidectin/imidacloprid appeared to be effective and safe against generalized adult onset canine demodicosis associated with hyperadrenocorticism.  相似文献   

3.
Milk progesterone determination in buffaloes post-insemination   总被引:1,自引:0,他引:1  
Milk progesterone levels were studied in 17 buffaloes between post-insemination and 30 days thereafter. Six animals were confirmed pregnant. Seven of 10 animals took greater than 24 days to return to oestrus and the pattern of change of progesterone levels indicated a steady increase from 1 ng/ml on day 2 to 20 ng/ml on day 14 post-insemination, falling subsequently to about 5 ng/ml, 2 days prior to oestrus. In pregnant buffaloes, the milk progesterone levels showed a continuous increase up to 20 days post-insemination but did not decline thereafter. In individual buffaloes returning to oestrus, a cut-off milk progesterone level of greater than 10 ng/ml was considered for pregnancy diagnosis, 20, 22 and 24 days post-insemination. The test was 60, 75 and 75% accurate for detection of pregnancy on days 20, 22 and 24 respectively and 100% for non-pregnancy diagnosis on all three days. Individual animals showed a highly variable oestrous cycle length, which has been suggested as a contributory factor for false pregnancy diagnosis by milk progesterone test in this species. Milk progesterone assay may also identify silent heats, and clinical disorders.  相似文献   

4.

Background

The four Nordic countries: Denmark (DK), Finland (FIN), Norway (NO) and Sweden (SE), all have national databases in which mainly records of treated animals are maintained. Recently, the completeness of locomotor disorder records in these databases has been evaluated using farmers’ recordings as a reference level. The objective of the present study was to see how previous estimates of completeness figures are affected by the criteria determining whether a recording in the database is to be judged correct. These demands included date of diagnosis and disease classification. In contrast with the previous study, a period of time between the date of disease recording in the database and by the farmer was allowed. Further, the calculations were brought to bear on individual locomotor diagnoses instead of a common locomotor disease complex code.

Methods

Randomly selected dairy herds (≥ 15 cows) were invited to participate. During two 2-month periods in 2008 the farmers recorded the diseases they observed on the farm and their recordings constituted a farmer database (FD). These recordings were compared to disease recordings in the National Databases (ND). Earlier calculations of completeness for locomotor complex cases assuming an exact match on date were compared with ±7 day and ±30 day discrepancies calculated in this study.

Results

The farmers in DK, FIN, NO and SE recorded 426, 147, 97 and 193 locomotor disorders, respectively. When a window of ±7 days was allowed there was a relative increase in completeness figures lying in the range of 24–100%. Further increases were minor, or non-existent, when the window was expanded to ±30 days. The same trend was seen for individual diagnoses.

Conclusion

In all four of the Nordic countries a common pattern can be observed: a further increase in completeness occurs when individual locomotor diagnoses recorded by the farmer are permitted to match any locomotor diagnosis recorded in the ND. Completeness increased when both time span and different diagnoses within the locomotor complex were allowed.  相似文献   

5.

Background

The effect of time of fecal sampling on the accuracy of acid-detergent insoluble ash (ADIA) and alkaline-peroxide lignin (APL) for the prediction of fecal output (FO) in cattle was evaluated. Eight ruminally cannulated cows (594 ± 35.5 kg) were allocated randomly to 4 bermudagrass [Cynodon dactylon (L.) Pers.] hay diets markedly different in crude protein concentration (79–164 g/kg) with 2 replicates per diet for 3 periods. Cows were offered hay individually at 20 g DM/kg of body weight daily in equal feedings at 08:00 and 16:00 h for a 10-d adaptation period followed by 5-d of total fecal collection. Fecal grab samples also were taken each day during the fecal collection period at 06:00, 12:00, 18:00, and 24:00 h either directly from the rectum or from freshly voided feces. Samples were composited within cow and time across the 5 d total fecal collection period. Additionally, forage, ort, and fecal samples were analyzed for concentrations of APL and ADIA.

Results

Fecal concentrations of ADIA and APL were not affected by sampling time (P ≥ 0.22), even though diet affected (P < 0.01) fecal ADIA and APL concentrations. There were no diet × sampling time interactions (P ≥ 0.60). Estimates of FO and dry matter digestibility (DMD) from ADIA and APL were not affected (P ≥ 0.16) by sampling time or the diet × sampling time interaction (P ≥ 0.74). Estimates of FO and DMD from markers from different sampling times or all different combinations of sampling time were not different (P ≥ 0.72) from those of total collection among internal markers.

Conclusion

Little variation in concentrations of ADIA and APL in daily fecal excretion across time increases flexibility in fecal grab sampling schedules for predicting FO and DMD.  相似文献   

6.

Background

Calf disease may result in great economic losses. To implement prevention strategies it is important to gain information on management and to point out risk factors. The objective of this internet based survey was to describe calf management practices on registered dairy breeding farms in Austria and to estimate differences in calf disease incidences depending on farm structure and management practices.

Results

A total of 1287 questionnaires were finally analysed (response rate 12.2 %). Herd characteristics and regional distribution of farms indicated that this survey gives a good overview on calf management practices on registered dairy farms in Austria. The median number of cows per farm was 20 (interquartile range 13–30). Significant differences regarding farm characteristics and calf management between small and large farms (≤20 vs >20 cows) were present. Only 2.8 % of farmers tested first colostrum quality by use of a hydrometer. Storing frozen colostrum was more prevalent on large farms (80.8 vs 64.2 %). On 85.1 % of the farms, whole milk, including waste milk, was fed to the calves. Milk replacer and waste milk were more often used on large farms. In accordance with similar studies from other countries, calf diarrhoea was indicated as the most prevalent disease. Multivariable logistic regression analysis revealed that herd size was associated with calf diarrhoea and calf respiratory tract disease, with higher risk of disease on large farms. Furthermore, feeding waste milk to the calves was associated with increasing calf diarrhoea incidence on farm. In the final model with calf respiratory tract disease as outcome, respondents from organic farms reported less often a respiratory tract disease incidence of over 10 % compared with conventional farms [odds ratio (OR) 0.40, 95 % confidence interval (CI) 0.21–0.75] and farmers that housed calves individually or in groups after birth significantly reported more often to have an incidence of respiratory tract disease >10 % compared with farms where all calves were housed individually (OR 2.28, 95 % CI 1.16–4.48).

Conclusion

The results obtained in this study provide an overview on calf management on dairy breeding farms in Austria and may help to further point out areas to be improved on farm.

Electronic supplementary material

The online version of this article (doi:10.1186/s13028-015-0134-y) contains supplementary material, which is available to authorized users.  相似文献   

7.

Background

The aim of the present study was to investigate the efficacy of the Improvac on testosterone concentration in blood serum, sexual behavior and sperm quality in matured AI boars. A total of nine Danish Landrace AI boars were included in the analysis.

Methods

The trial period lasted for 15 weeks and was divided into four periods: Control period: three weeks before vaccination; Period I – four weeks after first vaccination; Period II – four weeks after second vaccination, Period III – four weeks after third vaccination. Blood and sperm samples were collected at weekly intervals. Freshly collected sperm samples were analyzed.

Results

Testosterone concentration correlated with libido (r = 0.531; p < 0.001), volume of ejaculate (r = 0.324; p < 0.001) and the percentage of morphologically normal spermatozoa (r = 0.207; p < 0.05). Testosterone concentration rised significantly (p < 0.05) in 5–6 week of trial, e. i. after the first dose of Improvac and after this peak the level of testosterone further progressively decreased (p < 0.05).

Conclusions

Results from this study indicate that active immunization of sexually matured boars against GnRH has negative impact on testosterone concentration, sexual behavior, volume of ejaculate and total number of normal spermatozoa in ejaculate.  相似文献   

8.

Background

As a member of the Paramyxoviridae group, Newcastle disease virus (NDV) is the key causative agent of Newcastle disease (ND) that attacks chickens, turkeys and other avian birds. Surviving birds showed lower feed utilization, growth performance or egg production, which results in severe economic losses. The purpose of this study was to determine the effect of different doses of NDV immunization on growth performance, plasma variables and immune response of broiler chickens.

Methods

A total of 480 one-day-old Arbor Acres broilers were randomly administrated with 0, 4, 6 or 8 doses of NDV at 12 d and 28 d, respectively. Each group consisted of ten replicates with 12 birds each. Growth performance and organ weight were recorded. Plasma concentration of glucose, total protein, cholesterol, triglycerides and nonesterified fatty acid was determined using commercial kits. The concentration of plasma corticosterone and insulin was measured using commercially available radio immune assay kits. Serum antibody titer and peripheral blood lymphocyte proliferation were also recorded.

Results

The results showed that NDV decreased body weight gain (BWG), and increased Feed:Gain ratio at 1–21 d at all doses (P < 0.05). Plasma insulin concentration was lower in all immunization groups after the first immunization at 12 d (P < 0.01). The rest of the plasma indexes were not affected by NDV immunization, including glucose, total protein, cholesterol, triglycerides, nonesterified fatty acid, heterophil/lymphocyte ratio, as well as the proliferation of peripheral blood lymphocyte (P > 0.05). Compared with the control group, NDV treatment elevated NDV antibody titer at 10 d after the first inoculation (P < 0.05), and at d 5, 9 and 13 after the second inoculation (P < 0.05). Repeated NDV inoculation had no deleterious impacts on body composition at 42 d, and nutrient accretion rates at 8–42 d (P > 0.05).

Conclusions

In conclusion, NDV challenge decreased BWG and feed efficiency in earlier stage of growth. However, NDV treatment at 6 doses down-regulated the Feed:Gain ratio by 6.36 % throughout the whole growing period. These data suggest that appropriate lower doses of NDV inoculation increase feed efficiency of broiler chickens.

Electronic supplementary material

The online version of this article (doi:10.1186/s40104-015-0019-y) contains supplementary material, which is available to authorized users.  相似文献   

9.

Background

The aim of the study was to test the effect of two treatments in cases of acute puerperal metritis (APM) and clinical metritis (CM).

Methods

Cows with APM and CM (n = 40)) were matched according to plasma fibrinogen levels (Fb) into three groups. Two negative control groups D (n = 11) and E (n = 17) were composed of healthy cows. The proportion of animals with APM and CM was similar within the groups. Treatment was started on the 3rd day postpartum (PP). In group A (n = 15), intramuscular (i.m.) administration of ceftiofur was used for five days in combination with flunixin for three days. Group B (n = 15) received i.m. administration of ceftiofur for five days followed by two injections of prostaglandin F2α, with an interval of 8 h, on the 8th day PP. Group C (n = 10) served as a control group with no treatment. The general health status, body temperature (BT) and vaginal discharge were evaluated daily. Endometrial biopsies for bacteriology were taken once a week for seven weeks PP. Blood samples for the analysis of acute phase proteins were collected once a week for six weeks PP. Samples for progesterone analysis were taken twice a week for seven weeks PP. Fertility performance data were recorded.

Results

The area under the curve of BT was higher in group B than in group D cows (P < 0.05). No differences were found for vaginal discharge. There were no differences in bacterial growth, start of ovarian activity or serum amyloid-A or fibrinogen levels among the groups. The haptoglobin concentration was higher in the first and second weeks PP in group B compared with the other groups (P < 0.05). The number of days open was higher in group A than in both groups B and D (P < 0.05). The pregnancy rate after the first two services was higher (P < 0.05) in groups B and D than in groups A and C. The number of services per pregnancy was lower in group B than in group C (P < 0.05).

Conclusions

Regardless of more severe uterine inflammation found in animals from group B, these cows showed the same fertility parameters as healthy animals.  相似文献   

10.

Background

The main objective of this study was to estimate the effect of supplementation with Saccaromyces cerevisiae (SC) (Yea-Sacc® 1026) on milk production, metabolic parameters and the resumption of ovarian activity in early lactation dairy cows.

Methods

The experiment was conducted during 2005/2006 in a commercial tied-house farm with an average of 200 milking Estonian Holstein Friesian cows. The late pregnant multiparous cows (n = 46) were randomly divided into two groups; one group received 10 g yeast culture from two weeks before to 14 weeks after calving. The groups were fed a total mixed ration with silages and concentrates. Milk recording data and blood samples for plasma metabolites were taken. Resumption of luteal activity was determined using milk progesterone (P4) measurements. Uterine bacteriology and ovarian ultrasonography (US) were performed and body condition scores (BCS) and clinical disease occurrences were recorded. For analysis, the statistical software Stata 9.2 and R were used to compute Cox proportional hazard and linear mixed models.

Results

The average milk production per cow did not differ between the groups (32.7 ± 6.4 vs 30.7 ± 5.3 kg/day in the SC and control groups respectively), but the production of milk fat (P < 0.001) and milk protein (P < 0.001) were higher in the SC group. There was no effect of treatment on BCS. The analysis of energy-related metabolites in early lactation showed no significant differences between the groups. In both groups higher levels of β-hydroxybutyrate (BHB) appeared from days 14 to 28 after parturition and the concentration of non-esterfied fatty acid (NEFA) was higher from days 1–7 post partum (PP). According to US and P4 results, all cows in both groups ovulated during the experimental period. The resumption of ovarian activity (first ovulations) and time required for elimination of bacteria from the uterus did not differ between the groups.

Conclusion

Supplementation with SC had an effect on milk protein and fat production, but did not influence the milk yield. No effects on PP metabolic status, bacterial elimination from the uterus nor the resumption of ovarian activity were found.  相似文献   

11.

Background

Ketoprofen is a non-steroidal anti-inflammatory drug which has been widely used for domestic animals. Orally administered racemic ketoprofen has been reported to be absorbed well in pigs, and bioavailability was almost complete. The objectives of this study were to analyze R- and S-ketoprofen concentrations in plasma after oral (PO) and intra muscular (IM) routes of administration, and to assess the relative bioavailability of racemic ketoprofen for both enantiomers between those routes of administration in growing pigs.

Methods

Eleven pigs received racemic ketoprofen at dose rates of 4 mg/kg PO and 3 mg/kg IM in a randomized, crossover design with a 6-day washout period. Enantiomers were separated on a chiral column and their concentrations were determined by liquid chromatography-tandem mass spectrometry. Pharmacokinetic parameters were calculated and relative bioavailability (Frel) was determined for S and R –ketoprofen.

Results

S-ketoprofen was the predominant enantiomer in pig plasma after administration of the racemic mixture via both routes. The mean (± SD) maximum S-ketoprofen concentration in plasma (7.42 mg/L ± 2.35 in PO and 7.32 mg/L ± 0.75 in IM) was more than twice as high as that of R-ketoprofen (2.55 mg/L ± 0.99 in PO and 3.23 mg/L ± 0.70 in IM), and the terminal half-life was three times longer for S-ketoprofen (3.40 h ± 0.91 in PO and 2.89 h ± 0.85 in IM) than R-ketoprofen (1.1 h ± 0.90 in PO and 0.75 h ± 0.48 in IM). The mean (± SD) relative bioavailability (PO compared to IM) was 83 ± 20% and 63 ± 23% for S-ketoprofen and R-ketoprofen, respectively.

Conclusions

Although some minor differences were detected in the ketoprofen enantiomer concentrations in plasma after PO and IM administration, they are probably not relevant in clinical use. Thus, the pharmacological effects of racemic ketoprofen should be comparable after intramuscular and oral routes of administration in growing pigs.  相似文献   

12.

Background

Bovine viral diarrhoea (BVD) is considered eradicated from Denmark. Currently, very few (if any) Danish cattle herds could be infected with BVD virus (BVDV). The Danish antibody blocking enzyme-linked immunosorbent assay (ELISA) has been successfully used during the Danish BVD eradication program, initiated in 1994. During the last decade, the cattle herd size has increased while the prevalence of BVDV has decreased. In this study, we investigated how these changes could affect the performance of the Danish blocking ELISA and of the SVANOVIR®BVDV-Ab indirect ELISA. The latter has successfully been used to eradicate BVD in Sweden.Data (2003–2010) on changes in median herd size and milk production levels, occurrence of viremic animals and bulk milk surveillance were analysed. Additionally, the Danish blocking ELISA and the SVANOVIR ELISA were compared analyzing milk and serum samples. The prevalence of antibody positive milking cows that could be detected by each test was estimated, by diluting positive individual milk samples and making artificial milk pools.

Results

During the study period, the median herd size increased from 74 (2003) to 127 cows (2010), while the prevalence of BVDV infected herds decreased from 0.51 to 0.02 %. The daily milk yield contribution of a single seropositive cow to the entire daily bulk milk was reduced from 1.61 % in 2003 to 0.95 % in 2010 due to the increased herd size. It was observed that antibody levels in bulk milk decreased at national level. Moreover, we found that when testing bulk milk, the SVANOVIR®BVDV-Ab can detect a lower prevalence of seropositive lactating cows, compared to the Danish blocking ELISA (0.78 % vs. 50 %). Values in the SVANOVIR®BVDV-Ab better relate to low concentrations of antibody positive milk (R2 = 94-98 %), than values in the blocking ELISA (R2 = 23–75 %). For sera, the two ELISAs performed equally well.

Conclusions

The SVANOVIR ELISA is recommended for analysis of bulk milk samples in the current Danish situation, since infected dairy herds e.g. due to import of infected cattle can be detected shortly after BVDV introduction, when only few lactating cows have seroconverted. In sera, the two ELISAs can be used interchangeably.  相似文献   

13.

Background

Overwintering (breeding) reindeer (Rangifer tarandus tarandus) are commonly treated with ivermectin against parasitic infestations once yearly in autumn-winter roundups. The only preparations registered to reindeer are those for subcutaneous injection. However, also oral extra-label ivermectin administration is used. Twenty-six, 8-month-old reindeer calves were randomly allocated into three groups. Group 1 (n = 9) received oral ivermectin mixture (Ivomec® vet mixt. 0.8 mg/ml, oral ovine liquid drench formulation), Group 2 (n = 9) oral ivermectin paste (Ivomec® vet 18.7 mg/g equine paste), and Group 3 (n = 8) subcutaneous injection of ivermectin (Ivomec® 10 mg/ml vet inj.), each group at a dose of 200 μg/kg body weight. Blood samples were collected at treatment and at days 1, 2, 3, 6, 9 and 16 post treatment. Plasma concentrations of ivermectin were determined by high-pressure liquid chromatography (HPLC) with fluorescence detection.

Results

The peak plasma concentration (Cmax) was reached by 2 days after each treatment. The Cmax and Area Under Curve (AUC) differed significantly between the groups: Cmax was 30.2 ± 3.9, 14.9 ± 5.7 and 63.1 ± 13.1 ng/ml, and AUC was 2881 ± 462, 1299 ± 342 and 6718 ± 1620 ng*h/ml for groups 1, 2 and 3, respectively (mean ± standard deviation).

Conclusions

The differences in plasma concentrations of ivermectin are concomitant with earlier observed differences in antiparasitic efficacy, which discounts the use of the equine paste in reindeer in favour of the oral ovine liquid drench formulation, or preferably, the reindeer-registered subcutaneous injection formulation.  相似文献   

14.

Background

Intrauterine infusions have been widely used for the treatment of endometritis in the mare. Nevertheless, their consequences on endocrine and endometrial molecular aspects are unknown. We studied the effect of a 1% povidone-iodine solution intrauterine infusion on progesterone levels, endometrial histology and estrogen (ERα) and progesterone (PR) receptor distribution by immunohistochemistry.

Methods

Fourteen healthy mares were used in this study. Estruses were synchronized and seven mares were treated with intrauterine infusions at days 0 and 2 post ovulation of two consecutive estrous cycles. Uterine biopsy samples were taken on days 6 and 15 post ovulation.

Results

The treatment did not induce an inflammatory response indicating endometritis, neither affected the ERα. However, it reduced the percentage of PR positive cells (PPC) on day 6 (deep glandular epithelium, control: 95.7 vs. infused: 61.5, P < 0.05). Treated mares tended to have lower progesterone levels on day 2 (3.9 ng/ml vs. 6.6 ng/ml, P = 0.07), and higher levels on day 15 compared with controls (4.4 ng/ml vs. 1.3 ng/ml, P = 0.07).

Conclusion

a 1% povidone-iodine infusion during days 0 and 2 post ovulation in healthy mares did not induce histological changes indicating endometritis, but altered progesterone concentrations and reduced the expression of endometrial PR at day 6 without affecting the ERα. These changes could reduce embryo survival.  相似文献   

15.

Background

During nutritional stress, reduced intake may reduce the efficacy of anabolic implants. This study was conducted to evaluate basic cellular responses to a growth promotant implant at two intake levels.

Methods

Sixteen crossbred steers (293 ± 19.3 kg) were used to evaluate the impact of anabolic implants in either an adequate or a restricted nutritional state. Steers were trained to individual Calan gates, and then randomly assigned to 1 of 4 treatments in a 2 × 2 factorial arrangement. Treatments consisted of: presence or absence of an anabolic growth implant (Revalor-XS, 200 mg TBA and 40 mg estradiol; IMPLANT or CONTROL) and a moderate energy, pelleted, starting cattle diet fed at either 2.0 × or 1.0 × maintenance energy (NEM) requirements (HIGH or LOW). Serum (d 0, 14, and 28) was used for application to bovine muscle satellite cells. After treatment with the serum (20% of total media) from the trial cattle, the satellite cells were incubated for 72 h. Protein abundance of myosin heavy chain (MHC), phosphorylated extracellular signal-related kinase (phospho-ERK), and phosphorylated mammalian target of rapamycin (phospho-mTOR) were analyzed to determine the effects of implant, intake, and their interaction (applied via the serum).

Results

Intake had no effect on MHC (P = 0.85) but IMPLANT increased (P < 0.01) MHC abundance vs. CONTROL. Implant status, intake status, and the interaction had no effect on the abundance of phospho-ERK (P ≥ 0.23). Implanting increased phospho-mTOR (P < 0.01) but there was no effect (P ≥ 0.51) of intake or intake × implant.

Conclusions

The nearly complete lack of interaction between implant and nutritional status indicates that the signaling molecules measured herein respond to implants and nutritional status independently. Furthermore, results suggest that the muscle hypertrophic effects of anabolic implants may not be mediated by circulating IGF-1.  相似文献   

16.

Background

Reproduction is the single greatest factor limiting beef cattle production. Previous research on beef suckler luteal activity has largely focused on the mechanisms, and duration, of postpartum anoestrus. However, the temporal pattern of luteal activity after resumption of post-partum ovarian activity, and the impact of pattern type on days open (DO) in purebred beef suckler cows, are unknown.

Methods

Progesterone concentration was measured in milk samples taken thrice weekly from 120 lactations, in 87 animals, on 3 farms, over two years. Onset of luteal activity (OLA) was defined as the first day milk progesterone concentration exceeded 3 ng/ml for two successive measurements, or exceeded 5 ng/ml once. It was defined as delayed if it occurred more than 61 days postpartum. A short initial luteal phase consisted of progesterone concentrations which exceeded 3 ng/ml for fewer than 4 sequential measurements. Temporal progesterone patterns were classified as: 1) Normal cyclicity; 2) Cessation of luteal activity; 3) Prolonged luteal activity; 4) Erratic phase: failure to conform to 1, 2 or 3. Data concerning parity, previous calving interval, breeding values, calf birth and 200-d weight were obtained from the Norwegian Beef Cattle Recording System database.

Results

The mean (SD) OLA was 41 d (20). Parity and calf birth weight were inversely correlated with OLA. Delayed OLA occurred in 14.4% of lactations. A short first luteal phase occurred in 61.5% of lactations, but this was unrelated to irregular luteal phase occurrence, pregnancy or DO. Irregular luteal phases occurred in 22% of lactations. The irregularities were: prolonged luteal phase (11%); cessation of luteal activity (5%); erratic luteal activity (6%). Early OLA was associated with prolonged luteal phases. DO was positively correlated with irregular luteal phases and negatively correlated with calf 200-d weight.

Conclusions

This study demonstrates that irregular luteal phases negatively affect reproductive performance in purebred beef suckler cattle. A moderate incidence of irregular luteal phases was seen in the study population. Whilst a positive relationship was seen between OLA and DO, unfavourable associations between early OLA and incidence of irregular luteal phases should be considered when developing breeding programmes.  相似文献   

17.

Background

One of the challenges faced by equine breeders is ensuring delivery of good quality semen doses for artificial insemination when the mare is due to ovulate. Single Layer Centrifugation (SLC) has been shown to select morphologically normal spermatozoa with intact chromatin and good progressive motility from the rest of the ejaculate, and to prolong the life of these selected spermatozoa in vitro. The objective of the present study was a proof of concept, to determine whether fertilizing ability was retained in SLC-selected spermatozoa during prolonged storage.

Findings

Sixteen mares were inseminated with SLC-selected sperm doses that had been cooled and stored at 6°C for 48 h, 72 h or 96 h. Embryos were identified in 11 mares by ultrasound examination 16–18 days after presumed ovulation.

Conclusion

SLC-selected stallion spermatozoa stored for up to 96 h are capable of fertilization.  相似文献   

18.

Background

The prevalence of Toxoplasma gondii in free range chickens is a good indicator of the prevalence of T. gondii oocysts in the environment. The aim of this study was to isolate T. gondii parasites from heart and brain of seropositive free range (FR) chickens.

Findings

Isolation of T. gondii from pooled heart and brain of 41 direct agglutination test (DAT) positive (≥1:40) free range chickens (Gallus domesticus) was carried out by bioassay in mice. T. gondii specific antibodies in mice were assayed by DAT and microscopy was employed for detection and enumeration of brain tissue cysts. Overall, bioassay was positive in 29 (70.7%) chicken samples. T. gondii tissue cysts were isolated from 59% (24/41) of bioassayed chickens: from 2 of 7 chickens with a titer of 1: ≤ 60, 2 of 5 with titer 1: 180, 6 of 8 with titer 1: 540, 10 of 15 with titer 1: 1620, 1 of 2 with titer 1: 6000, 2 of 3 with titer 1:18000, 1 of 1 with titer 1:54000. None of the isolates was pathogenic for mice. Tissue cysts were detected from 61% of seropositive mice (DAT ≥ 1:40). Generally, tissue cyst counts per brain of mouse were low (mean: 132.7 ± 84.4; range: 47–352).

Conclusions

Majority of T. gondii seropositive chickens (Gallus domesticus) in Central. Ethiopia carries the infective parasite. Tissues from the free range chicken might be a source infection for animals and humans.  相似文献   

19.

Background

Fasciola hepatica is a helminth parasite of global importance in livestock, with major economic impact. However information on F. hepatica infections in Irish pasture-based dairy herds is limited. Therefore this study was conducted in order to determine the prevalence, seasonality and management factors associated with F. hepatica. A total of 319 Irish dairy herds were selected for this study. Bulk tank milk (BTM) samples were collected from 290 dairy farms on a quarter year basis, while from a further 29 dairy farms BTM samples were collected on a monthly basis to provide a more detailed pattern of F. hepatica exposure in Irish herds. BTM samples were analysed using a commercially available F. hepatica antibody detection ELISA. Furthermore, within-herd prevalence of F. hepatica was assessed in a subset of these 29 herds (n = 17); both individual serum samples and bulk tank milk samples were collected.

Results

A within-herd prevalence of ≤ 50 % was found for herds with negative bulk tank milk samples. The mean prevalence of the 290 study herds was 75.4 % (Range 52 %–75.1 %), with the highest prevalence being observed in November (75.1 %). The seasonal pattern of F. hepatica shows elevated antibodies as the grazing season progressed, reaching a peak in January. A significant association was found between F. hepatica and age at first calving.

Conclusion

This study demonstrates that F. hepatica is present in a large proportion of Irish dairy herds and provides a basis on which control practices, particularly in adult dairy cows, can be reviewed.  相似文献   

20.

Background

The nutrient composition of corn is variable. To prevent unforeseen reductions in growth performance, grading and analytical methods are used to minimize nutrient variability between calculated and analyzed values. This experiment was carried out to define the sources of variation in the energy content of corn and to develop a practical method to accurately estimate the digestible energy (DE) and metabolisable energy (ME) content of individual corn samples for growing pigs. Twenty samples were taken from each of five provinces in China (Jilin, Hebei, Shandong, Liaoning, and Henan) to obtain a range of quality.

Results

The DE and ME contents of the 100 corn samples were measured in 35.3 ± 1.92 kg growing pigs (six pigs per corn sample). Sixty corn samples were used to build the prediction model; the remaining forty samples were used to test the suitability of these models. The chemical composition of each corn sample was determined, and the results were used to establish prediction equations for DE or ME content from chemical characteristics. The mean DE and ME content of the 100 samples were 4,053 and 3,923 kcal/kg (dry matter basis), respectively. The physical characteristics were determined, as well, and the results indicated that the bulk weight and 1,000-kernel weight were not associated with energy content. The DE and ME values could be accurately predicted from chemical characteristics. The best fit equations were as follows: DE, kcal/kg of DM = 1062.68 + (49.72 × EE) + (0.54 × GE) + (9.11 × starch), with R2 = 0.62, residual standard deviation (RSD) = 48 kcal/kg, and P < 0.01; ME, kcal/kg of dry matter basis (DM) = 671.54 + (0.89 × DE) – (5.57 × NDF) – (191.39 × ash), with R2 = 0.87, RSD = 18 kcal/kg, and P < 0.01.

Conclusion

This experiment confirms the large variation in the energy content of corn, describes the factors that influence this variation, and presents equations based on chemical measurements that may be used to predict the DE and ME content of individual corn samples.  相似文献   

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