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101.
This investigation evaluated the efficacy of a bacterin in reducing the prevalence of staphylococcal mastitis and somatic cell counts (SCC) in a dairy goat herd. Does were vaccinated or left as controls, and the levels of mastitis and SCC monitored over 18 months. Staphylococcus caprae (42.5%), S. xylosus (15.1%), and S. simulans (10.0%) were the predominant causes of intramammary infections (IMI). The infection rate was 1.64 IMI/doe among vaccinates, which tended to be lower (P < 0.12) than controls (2.67 IMI/doe). The spontaneous cure rate of IMI after immunization was 1.28 cures/doe in vaccinates, which was higher than controls (0.6 cures/doe; P < 0.043). Average SCC of milk samples from vaccinates tended to be lower than that of controls (1274 × 103/ml vs. 1529 × 103/ml, respectively) (P < 0.10). Results support the continued study of mastitis vaccines for use in managing staphylococcal mastitis and SCC in dairy goats.  相似文献   
102.
Fifty-one dogs (27 diabetic dogs, four that had recovered from diabetes and 20 healthy control dogs) were given 0.5 or 1.0 mg glucagon intravenously. Blood samples were taken before the injection and 10 and 20 minutes after it. Samples were analysed to determine C-peptide, insulin and glucose concentrations, and one sample from each dog was analysed for fructosamine. The median (interquartile range) concentrations of C-peptide in the samples taken at 10 minutes were 0.5 (0.3 to 0.8) nmol/l in the control dogs, 0.1 (0 to 0.2) nmol/l in the diabetic dogs, and 0.3 (0.2 to 0.4) nmol/l in the dogs that had recovered from diabetes. Seven of the 51 dogs showed mild adverse reactions after the injection of glucagon.  相似文献   
103.
Colloid goitre was diagnosed in adult camels in the Kordofan region of the Sudan. The disease is characterized by gross enlargement of the thyroid, histopathological follicular changes, reproductive disorders, low concentrations of circulating thyroid hormones (T3, T4) and normocytic normochromic anaemia. The possible cause of the condition is discussed and iodine supplementation is recommended.  相似文献   
104.
A 4th of 667 cattle examined at a Wisconsin abattoir had teat papillomas. Excised teat papillomas were sorted by gross morphologic characteristics into 3 groups: (i) atypical filiform, (ii) atypical flat, and (iii) typical fibropapilloma. Bovine papilloma virus capsid antigen was detected in thin-section slides of the 3 groups of teat papillomas by peroxidase-antiperoxidase assay. The bovine papilloma virus involved with the atypical papillomas could not be characterized by molecular hybridization, because enough pure virus could not be harvested. Homogenates of the 3 groups of teat papillomas were inoculated on 2 ponies and 4 calves. Typical fibropapillomas were produced on the 4 calves, and fibromas, on the 2 ponies. Atypical papillomas were produced only in 2 heifers.  相似文献   
105.
Disease prevalence in turkeys was estimated by totaling the flock size of necropsy cases submitted to the University of Georgia in 1986 for each disease reported and comparing it with the population at risk. Fowl cholera was the most prevalent disease in both commercial tom flocks (18.0%) and breeder hen flocks (14.7%). Prevalence of colibacillosis was 15.9% in commercial tom flocks, and prevalence of aspergillosis was 8.5% in commercial tom and 4.9% in breeder hen flocks.  相似文献   
106.
A histidine (HIS)-deficient, feather meal-corn-dried whey basal diet (19% protein and 3,200 Kcal ME/kg), supplemented with lysine, methionine and tryptophan, was employed to determine the HIS requirement of the growing pig between 10 and 20 kg live weight. Using a chick bioavailability growth assay, the HIS-deficient basal diet was found to contain .19% bioavailable HIS. A preliminary pig study established that the HIS-deficient basal diet was capable of supporting good growth of pigs when supplemented with sufficient L-HIS.HCl.H2O. In the second pig experiment, crossbred pigs with an average initial weight of 10 kg were kept in individual metabolism crates and were fed to appetite in two feedings the HIS-deficient basal diet supplemented with 0, .06, .12 or .18% L-HIS. Rate and efficiency of weight gain increased linearly between 0 and .12% supplemental HIS, but the highest supplemental level of HIS did not improve performance further. Plasma HIS increased, whereas plasma urea-N remained unchanged, as the level of dietary HIS increased. The third pig experiment employed narrower increments of .06, .09 or .12% supplemental HIS, and a linear response in both gain and feed efficiency occurred. Viewing all experiments together, the bioavailable HIS requirement of the 10- to 20-kg pig was .31% of the diet. Assuming an 85% bioavailability of HIS in commercial diets based on corn and soybean meal, the total HIS level needed in practice would be .36%.  相似文献   
107.
The identification of QTL related to production traits that are relevant for the pig industry has been mostly performed by using divergent crosses. The main objective of the current study was to investigate whether these growth, fatness, and meat quality QTL, previously described in diverse experimental populations, were segregating in a Landrace commercial population selected for litter size, backfat thickness, and growth performance. We have found QTL for carcass weight (posterior P > 0.75), cutlet weight (posterior P > 0.99), weight of ham (posterior P > 0.75), shoulders weight (posterior probability > 0.99), and shear firm-ness (posterior P > 0.99) on pig Chromosome 2. Moreover, QTL with posterior P > 0.75 for fat thickness between the 3rd and 4th ribs (Chromosome 7), rib weights (Chromosome 8), backfat thickness (Chromosomes 8, 9, and 10), and b Minolta color component (Chromosome 7) were identified. These results indicate that commercial purebred populations retain a significant amount of genetic variation, even for traits that have been selected for many generations.  相似文献   
108.
109.
The aim of this study was to estimate genetic parameters for BW of Angus cattle up to 5 yr of age and to discuss options for including mature weight (MW) in their genetic evaluation. Data were obtained from the American Angus Association. Only records from herds with at least 500 animals and with >10% of animals with BW at ≥ 2 yr of age were considered. Traits were weaning weight (WW, n = 81,525), yearling weight (YW, n = 62,721), and BW measured from 2 to 5 yr of age (MW2, n = 15,927; MW3, n = 12,404; MW4, n = 9,805; MW5, n = 7,546). Genetic parameters were estimated using an AIREML algorithm with a multiple-trait animal model. Fixed effects were contemporary group and departure of the actual age from standard age (205, 365, 730, 1,095, 1,460, and 1,825 d of age for WW, YW, MW2, MW3, MW4, and MW5, respectively). Random effects were animal direct additive genetic, maternal additive genetic, maternal permanent environment, and residual. Estimates of direct genetic variances (kg(2)) were 298 ± 71.8, 563 ± 15.1, 925 ± 52.1, 1,221 ± 65.8, 1,406 ± 80.4, and 1,402 ± 66.9; maternal genetic variances were 167 ± 4.8, 153 ± 6.1, 123 ± 9.1, 136 ± 12.25, 167 ± 18.0, and 110 ± 14.0; maternal permanent environment variances were 124 ± 2.9, 120 ± 4.3, 61 ± 7.5, 69 ± 11.9, 103 ± 15.9, and 134 ± 35.2; and residual variances were 258 ± 3.8, 608 ± 8.6, 829 ± 34.2, 1,016 ± 38.8, 1,017 ± 52.1, and 1,202 ± 63.22 for WW, YW, MW2, MW3, MW4, and MW5, respectively. The direct genetic correlation between WW and YW was 0.84 ± 0.14 and between WW and MW ranged from 0.66 ± 0.06 (WW and MW4) to 0.72 ± 0.11 (WW and MW2). Direct genetic correlations ranged from 0.77 ± 0.08 (YW and MW5) to 0.85 ± 0.07 (YW and MW2) between YW and MW, and they were ≥ 0.95 among MW2, MW3, MW4, and MW5. Maternal genetic correlations between WW and YW and MW ranged from 0.52 ± 0.05 (WW and MW4) to 0.95 ± 0.07 (WW and YW), and among MW they ranged from 0.54 ± 0.14 (MW4 and MW5) to 0.94 ± 0.07 (MW2 and MW3). Genetic correlations suggest that a genetic evaluation for MW may be MW2-based and that including BW from older ages could be accomplished by adjusting records to the scale of MW2.  相似文献   
110.
The aim of this study was to assess the effects of 2 different phytogenic products on performance, ileal nutrient digestibility, and composition of the intestinal microbiota. The 2 phytogenic products contained different essential oil mixtures (EOM) characterized by either menthol (Mentha arvensis; EOM-M) or cinnamon aldehyde (Cinnamomum aromaticum; EOM-C) as main constituents. Three treatments consisted of control diet without EOM addition and diets supplemented with EOM-M or EOM-C. Reproducibility of the effects was examined in 4 trials with a total of 300 male castrated and female piglets weaned at 25 d of age. The number of pens per treatment in trials I through III were 7, 9, and 9, respectively, for research station conditions, and 10 in trial IV for simulated farm conditions. In research station conditions, the experimental unit consisted of flat deck pens with 2 piglets per pen, whereas it consisted of floor pens with straw bedding with 5 piglets per pen in farm conditions. The feed additives had no effect on feed intake or BW gain. Improvements (P < 0.05) in G:F were observed for EOM-M supplemented diets in 2 of 4 trials as well as for the combined data of all trials. These improvements were associated with greater (P<0.05) apparent ileal digestibility of CP and of most AA. The effect of EOM-C on these response criteria was intermediate between control and EOM-M. Real-time PCR analysis of the gastrointestinal contents for 7 bacterial groups (Lactobacillus spp., Enterococcus spp., Clostridium coccoides and Clostridium leptum cluster, Escherichia spp., and Escherichia coli toxin estII) indicated no effect of treatments on the gastrointestinal microbiota. It was concluded that EOM-M consistently improved feed efficiency in weaned piglets, and it was associated with improved ileal protein and AA digestibility. In general, however, the effectiveness of EOM as feed additives differs considerably depending on the constituents.  相似文献   
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