Density-Dependent Growth and Survival of Penaeus setiferus and Penaeus vannamei in a Semi-Closed Recirculating System     

A. S. Williams    D. A. Davis  C. R. Arnold 《Journal of the World Aquaculture Society》1996,27(1):107-112

Abstract.— Two growth trials utilizing Penaeus vannamei and Penaeus setiferus were conducted at densities of 28.4, 56.8, 85.2, 113.6, 170.4, 227.3 and 284.1/ m² in an indoor recirculating system. There was an inverse linear relationship between stocking density and growth among both species. The relationship between final weight and stocking density is described by the following linear equation: P. setiferus , Y =−0.00619X ± 4.46, adj. r²= 0.8572;. P. vannamei, Y =−0.00717X ± 7.39, adj. r²= 0.6230. Although the responses in terms of growth depressions were similar, P. setiferus growth was lower than that of P. vannamei . There was an inverse relationship between stocking density and survival for P. setiferus . Survival of P. vannamei was highly variable but was negatively correlated with density. Based on the results of the present study, P. setiferus has a similar tolerance of high density as that of P. vannamei and hence may be suitable for intensive culture systems. However, depressed growth rates of P. setiferus , which do not appear to be due to effects of water quality or density, must be solved if growth rates similar to P. vannamei are to be realized.  相似文献   

Learning capability as a testing method for brain damage caused by O2 deficiency     

P Arnold  E G?pfert  S Richter 《Archiv fuer experimentelle veterinaermedizin》1984,38(6):793-799

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Urinary incontinence in spayed female dogs: frequency and breed disposition     

S Arnold  P Arnold  M Hubler  M Casal  P Rüsch 《Schweizer Archiv für Tierheilkunde》1989,131(5):259-263

A follow up study was performed in 412 spayed bitches in order to determine the incidence of urinary incontinence. The period between the operation being performed and the survey being made varied between 3 and 10 years. 83 animals (20.1%) were incontinent independent of the surgical procedure (ovariectomy versus ovariohysterectomy). The onset of incontinence varied between immediately to 12 years with an average period of 2.9 years after surgery. 57 of these incontinent bitches were treated with ephedrine or estrogen. In 73.7% a good response was achieved with ephedrine and a further 23.7% showed some improvement. Generally ephedrine was more successful than estrogen in the treatment of incontinence. There appears to be a strong connection between body weight and the incidence of incontinence. Of bitches with a body weight of less than 20 kg only 9.3% were incontinent. Whereas in bitches with a body weight of more than 20 kg the incidence was 30.9%. Of the breeds Boxers showed a high incidence of incontinence (65%) while breeds such as German Shepherds (10.6%) or Dachshunds (11.1%) showed a low incidence in relation to the average incidence rate (20.1%).  相似文献   

Geklontes Kalb in Neustadt geboren     

J. Todorov  T. Todorova  U. Zimmermann  W.M. Arnold  C. Leiding  R. Hahn  J. Hahn 《Reproduction in domestic animals》1992,27(5):307-309

Am 27.8.1992 wurde beim Besamungsverein Neustadt (BVN) in Neustadt a.d. Aisch ein geklontes Fleckviehkalb geboren. Die Identität der Abstammung konnte eindeutig gesichert werden. Der erfolgreiche Kerntransfer in einem Versuchsprogramm soll belegen, daβ sich nach der Fusion einer Blastomere aus einem Spenderembryo mit einer in vitro gereiften und enukleierten Empfängeroozyte ein Embryo entwickeln kann, der nach Transfer auf ein Empfängertier zur Geburt eines gesunden Kalbes führt.
Contents: A cloned calf was born in Neustadt ad. Aisch
A cloned "Fleckvieh" calf was born at the Al-Association Neustadt (BVN) in Neustadt a.d. Aisch on August, 27, 1992. The identity of the parentage could be verified undoubtedly. The successful nuclear transfer in an experimental program showed that the fusion of a blastomere from a donor embryo with an in vitro matured and enucleated recipient oocyte led to the development of an embryo, and after transfer to a synchronous recipient to the birth of a healthy calf.  相似文献   

Fracture repair with transfixation pins and fiberglass cast in llamas and small ruminants   总被引：1，自引：0，他引：1  

A J Kaneps  W B Schmotzer  M J Huber  T W Riebold  B J Watrous  J S Arnold 《Journal of the American Veterinary Medical Association》1989,195(9):1257-1261

Transfixation pinning with fiberglass casting is an effective and adaptable method of longbone fracture fixation in llamas and small ruminants. Treatment of fractures in 7 limbs of 4 llamas and 2 small ruminants with this technique are described. Steinmann pins are placed transcortically proximal, and if necessary, distal to the fracture. The pin ends and limb are encased in fiberglass cast material. The cast is strong enough in animals of this size to eliminate the need for external frames or connecting bars. Severely comminuted fractures and fractures near joints are especially suited to fixation with this technique. Complications encountered in these cases included loosening of pins and one delayed union. All fractures healed to permit full use of the limb.  相似文献   

Sterile, purulent meningitis and generalized vasculitis caused by a new drug for prevention of nidation in the dog     

S K?lin  P Arnold  A Hagen  G Lott-Stolz  U Niederhauser  P Rüsch 《Schweizer Archiv für Tierheilkunde》1987,129(7):335-342

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Correlations of stomatal conductance with hydraulic, chemical and environmental variables in five urban tree species     

T. Brendon Johnson  Robert M. Aug  Craig D. Green  Ann J. W. Stodola  Joshua B. Olinick  Arnold M. Saxton 《Scientia Horticulturae》2001,90(3-4):305-320

Recent findings suggest that stomatal conductance (g_s) may be as closely linked to plant chemical variables as to hydraulic variables. To test this in an urban field setting, we examined seasonal g_s in relation to a number of plant and environmental variables in five temperate, deciduous tree species. Stomatal conductance was generally more closely correlated with abscisic acid concentrations in xylem sap than with shoot water potential, shoot osmotic potential, pH of xylem sap or environmental variables. Seasonal g_s was mostly poorly correlated with shoot water potential and osmotic potential. Among environmental variables, PPFD accounted for most variability in g_s. We tested a model, developed previously in maize, that describes regulation of g_s by abscisic acid concentration of xylem sap with leaf water status acting to modify stomatal sensitivity to the abscisic acid signal. This model explained somewhat more variation in g_s than abscisic acid concentrations alone. Response surface models, especially those incorporating environmental variables, were most successful at explaining g_s. Our findings with urban trees are consistent with the theory of regulation of g_s by root-sourced abscisic acid.  相似文献   

Clinical and serological diagnosis of ehrlichiosis in dogs in Switzerland     

G C Winkler  P Arnold  P Deplazes  O Glardon  H Lutz 《Schweizer Archiv für Tierheilkunde》1988,130(7):357-367

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Factors associated with time under quarantine for swine herds in the voluntary phase of the Illinois pseudorabies eradication program     

Arthur M. Siegel  Ronald M. Weigel  Arnold C. Taft 《Preventive veterinary medicine》1993,16(4):295-310

The association of herd characteristics and intervention strategies with time under quarantine was evaluated for 163 farrow-to-finish swine herds enrolled in the voluntary phase (1986–1987) of the pseudorabies virus (PRV) eradication program in the state of Illinois (USA). Vaccination was the intervention strategy used most widely (69% of herds), particularly in larger herds. Depopulation was used primarily when PRV seroprevalence was high, and test-and-removal when seroprevalence was low. Approximately 50% of the herds were released from quarantine within 3 years of developing a herd clean-up plan.

Multiple regression analysis using the Cox proportional hazards model indicated the following. Vaccination had a strong association with a longer time until release from quarantine (P<0.001). This is attributed to the lack of a vaccine differential test during this time, which made diagnosis of natural infection more difficult. Offspring segragation was associated with a longer time under quarantine (all herds: P=0.05; non-vaccinated herds: P=0.004). Delay in implementation of a herd clean-up plan was also associated with longer time under quarantine (all herds: P=0.012; non-vaccinated herds: P<0.001). Herds with higher seroprevalence at the time of agreement to a herd plan required a longer time under quarantine (all herds: P<0.001). This result was apparent for non-vaccinated herds (P=0.001), and thus is not merely a consequence of vaccination. Herds in areas with a high geographic density of quarantined herds required a longer time before release from quarantine (all herds: P=0.003), although this trend was not apparent for non-vaccinated herds (P=0.39). After taking PRV seroprevalence into account, there was no apparent association of time under quarantine with sow herd size (all herds: P=0.057; non-vaccinated herds: P=0.81) or confinement housing (all herds: P=0.19; non-vaccinated herds: P=0.91).  相似文献   

Effect of long- or short-term feeding of alpha-tocopheryl acetate to Holstein and crossbred beef steers on performance, carcass characteristics, and beef color stability.   总被引：1，自引：0，他引：1  

R N Arnold  K K Scheller  S C Arp  S N Williams  D R Buege  D M Schaefer 《Journal of animal science》1992,70(10):3055-3065

Three experiments were conducted to examine the effects of vitamin E supplementation on feedlot cattle. Vitamin E supplementation did not affect feedlot performance or carcass characteristics of cattle fed a high-concentrate diet (P greater than .1). The major finding was the effectiveness of vitamin E in extending the color stability of displayed beef (P less than .01). Color stability during display of longissimus lumborum steaks from cattle supplemented with 300 IU/d for 266 d, 1,140 IU/d for 67 d, or 1,200 IU/d for 38 d was extended by 2.5 to 4.8 d. Gluteus medius steaks had an extended color display life of 1.6 to 3.8 d. The accumulation of lipid oxidation products, but not aerobic microbes, associated with displayed longissimus lumborum was suppressed for muscle from vitamin E-supplemented steers. Taste panelists detected no difference among longissimus lumborum steaks from control and vitamin E-supplemented steers but found (P less than .01) steaks aged for 21 d to be more tender than steaks aged for 7 d. Supplementing cattle with vitamin E should reduce economic losses associated with discolored beef during retail display.  相似文献