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991.
The colostomised hens received 15N-labelled wheat. For a period of 8 days the incorporation of the 15N excess (15N') into the albumen, the yolk and the egg-shell was measured. In addition to that, the values for atom-percent of 15N' in the amino acids lysine, histidien and arginine of the albumen and the yolk were ascertained. The egg-shell and the albumen were labelled shortly after the beginning of the experiment. In both fractions the atom-per cent of 15N' rises more quickly than in the yolk. After the withdrawal of the labelled feed the decrease in the yolk was slower than in the egg-shell and the albumen. Concerning the atom-per cent of 15N' there is hardly a difference between the total N and the amino acids. Despite the different supply with amino acids, the relation of histidine 15N' : lysine 15N' : arginine-15N' in the yolk and the albumen remains largely constant. It is 1 : 2 : 3 and corresponds to the quantitative relation of the N content of the three amino acids in the egg protein. The utilisation of 14N and 15N' of the wheat lysin for the egg synthesis amounts to approximately 50%. There are considerable differences between the utilisation of 15N' of the histidine and 15N' of the arginine and the 14N of the two dietary amino acids.  相似文献   
992.
993.
A mature Brangus bull received the recommended dose of chlorpyrifos and became dull and inappetent 3 days later. Clinical findings included weakness, dehydration, rumen stasis, and rumen distention with fluid and gas. Blood cholinesterase activity was 25% of normal. The bull's condition improved after treatment with pralidoxime, antimicrobials, electrolyte solutions, vitamins, and adsorbents. Five weeks later, the bull had gained weight, the blood cholinesterase activity was 70% of normal, and the results of a semen evaluation indicated he was a satisfactory potential breeder.  相似文献   
994.
Avian rotaviruses were isolated from turkeys with enteritis using MA 104 cell line. MA 104 cells were suitable for primary isolation and propagation of avian rotaviruses. Trypsin appeared essential for the enhancement of infectivity and the occurrence of cytopathic effect (CPE). Serum neutralization (SN), electron microscopy (EM), and analysis of genomic RNA were done to identify and confirm the identity of rotaviruses. Electrophoretic migration patterns of genomic RNA from avian rotaviruses were examined, and they were compared with those from mammalian rotaviruses. The migration patterns differed between these groups.  相似文献   
995.
996.
Four subsamples of meat and bone meal (MBM) were heated (150 degrees C) for 0, 1.5, 3 and 5 h and then incorporated into four individual diets (100 g MBM/kg diet). The diets were precision-fed to 10 caecectomised and 10 intact adult cockerels. The apparent amino acid digestibility (ApAAD) and true amino acid digestibility (TAAD) of the diets were determined by analysis of the excreta. The digestibility coefficients measured using caecectomised birds were lower than those determined with intact birds. Coefficients of digestibility were statistically examined by analysis of variance for the effects of bird type (caecectomised or intact), type of calculation (apparent or true) and diet (heat-treatment) with and without accommodation for individual bird variability. If individual bird variability was not considered in the analysis the bird type X diet interactions (P less than 0.01) included glutamic acid, tyrosine and serine. When individual bird variability was included in the analysis, significant (P less than 0.01) bird type X diet interactions occurred for aspartic acid, serine, glutamic acid, leucine, tyrosine and lysine and the precision of the data was markedly improved. Amino acid digestibility using the precision-feeding procedure is affected by the selection of either intact or caecectomised birds.  相似文献   
997.
Data for gestation length, birth weight, calving difficulty (percent assisted) and survival from birth to weaning were analyzed from 4,639 calves by 290 sires of 14 Bos taurus breeds (Hereford, Angus, Jersey, South Devon, Limousin, Simmental, Charolais, Red Poll, Brown Swiss, Gelbvieh, Maine Anjou, Chianina, Pinzgauer and Tarentaise) mated to Hereford and Angus cows. The calves were produced over a 7-yr period in a germ plasm evaluation program. Variance components were estimated for breed of sire (sigma 2b), sire within breed of sire (sigma 2s) and progeny within sire (sigma 2w) random effects. Estimates of sigma 2b and sigma 2s direct genetic variance were similar for gestation length and calf survival. Estimates of sigma 2b genetic variance were greater than for sigma 2s for birth weight and calving difficulty. Estimates of total heritability [h2t = 4(sigma 2b + sigma 2s)/(4 sigma 2b + sigma 2s + sigma 2w)] and within-breed heritability (h2w = 4 sigma 2s/sigma 2s + sigma 2w) indicated that gestation length (h2t = .77, h2w = 64) and birth weight (h2t = .79, h2w = .46) are under a high degree of direct genetic control, calving difficulty (h2t = .42, h2w = .21) is under a moderate degree of direct genetic control and calf survival (h2t = .11, h2w = .07) is under a low degree of direct genetic control. Estimates of genetic correlation for between (rb) - and within-breed (rg) sources of genetic variation were comparable in direction, but tended to be stronger between than within breeds.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
998.
Weight, heartgirth, backfat and body condition of sows was monitored in a commercial, farrow-to-finish unit during 1 yr. Measurements were obtained during the third, ninth and fifteenth week of gestation and the day after weaning. Litter performance and rebreeding rate also were recorded. Body weight and heartgirth increased (P less than .01) over parities because gestational gains were larger than lactational losses. Backfat tended to be lower in later parities. Body weight, heartgirth and backfat, but not condition score, declined from weaning to the third week of the subsequent gestation in both first and second litter sows. Correlations among measures of body condition were low (less than .45), except the overall correlation between body weight and heartgirth. Number of pigs born alive increased and interval to estrus decreased in later parities. There were no significant relationships between changes in body condition and rebreeding performance of sows. These results suggest that changes in body condition typically observed in sows housed in commercial production units may be too subtle to have an effect on reproductive performance.  相似文献   
999.
Prevalence of canine uroliths. Minnesota Urolith Center   总被引:1,自引:0,他引:1  
Uroliths obtained from 839 dogs were evaluated by quantitative methods. Struvite was the most prevalent mineral detected; newberyite, calcium oxalate, calcium phosphate, uric acid, sodium and ammonium urate, cystine, and silica were detected much less frequently. Seven per cent of the uroliths had an identifiable nucleus and one or more surrounding layers of different mineral types. Although uroliths were found in all parts of the urinary tract, the urinary bladder was most common. Uroliths of different composition were encountered in a variety of breeds of both sexes and different ages.  相似文献   
1000.
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