An Econometric Estimation of Market Growth for the U.S. Processed Catfish Industry

Inadequate information pertaining to the growth potential of the US. processed catfish industry has been a major factor leading to cyclical periods of excess supply or demand resulting in misal-location of resources and price instability. Better information for industry planners (e.g., producers, processors, government regulatory agencies, and university researchers) on future sales potential would assist in decreasing the misuse of resources. An econometric model of wholesale demand for US. processed catfish was developed to provide estimates of future sales under various scenarios. In addition to the standard variables included in models of demand for food items—price, income, and population—the effects of product life cycle and industry-sponsored generic advertising are quantitatively incorporated. Seasonality of demand and rigidities in marketing and consumer behavior are additional considerations explicitly modeled via monthly dummy variables and a Ner-lovian partial adjustment mechanism, respectively.
Model results indicate the impact of alternative future price scenarios on wholesale processed caffish sales. At the mean real wholesale price of $1.60 (December 1988 dollars) for whole-dressed caffish and a real generic advertising expenditure of one million dollars postulated for 1995, projected aggregate sales are 219.2 million pounds, a 23% increase over 1989 sales. Projected 1995 wholesale sales are very sensitive to price with alternative price postulations of $1.40 and $1.80 resulting in projected sales of 252.3 and 193.6 million processed pounds, respectively. An estimated 7% average increase in wholesale sales of catfish was attributed to the industry-sponsored generic advertising campaign. Model projection estimates and impacts are posed as a quantitative source of information to be used with other information in resource allocation issues faced by industry decision makers.     

Genetic analyses of live-animal ultrasound and abattoir carcass traits in Australian Angus and Hereford cattle

In order to estimate genetic parameters, abattoir carcass data on 1,713 Angus and 1,007 Hereford steers and heifers were combined with yearling live-animal ultrasound measurements on 8,196 Angus and 3,405 Hereford individuals from seedstock herds. Abattoir measures included carcass weight (CWT), percentage of retail beefyield (RBY), near-infrared measured intramuscular fat percentage (CIMF), preslaughter scanned eye muscle area (CEMA), and subcutaneous fat depth at the 12th rib (CRIB) and at the P8 site (CP8). Ultrasound scans on yearling animals included 12th-rib fat depth (SRIB), rump fat depth at the P8 site (SP8), eye muscle area (SEMA), and percentage of intramuscular fat (SIMF). Records on CWT were adjusted to 650-d slaughter age, and the remaining abattoir traits were adjusted to 300-kg CWT. Scan data were analyzed treating records on males and females as different traits. Multivariate analyses were performed on a variety of trait combinations using animal model and REML algorithm. Heritability (h2) estimates for CWT, RBY, CIMF, CP8, CRIB, and CEMA were .31, .68, .43, .44, .28, and .26, respectively, for Angus and .54, .36, .36, .08, .27, .38, respectively, for Hereford. Pooled across sexes, h2 estimates for SIMF, SP8, SRIB, and SEMA were .33, .55, .51, and .42, respectively, for Angus and .20, .31, .18, and .38, respectively, for Hereford. Genetic correlations (r(g)) between the same pair of carcass traits measured at yearling through scanning and directly at the abattoir were moderate to strongly positive, suggesting that selection using yearling ultrasound measurements of seedstock cattle should result in predictable genetic improvement for abattoir carcass characteristics. Estimates of r(g) between the scanned fat measurements and RBY were negative, ranging from -.85 for Angus heifers to -.05 for Hereford heifers. Also, the estimates of r(g) between SEMA and the fat records measured at the abattoir were negative and ranged from -.94 in Hereford heifers to -.02 in Angus heifers.     

A survey of aquaculture production economics and management

Abstract

The literature on production economics and management of fish culture has grown as aquaculture has matured as a commercial industry. Salmon, catfish, shrimp and trout are the focus of this literature survey as a reflection of the volume of research that has been completed on these species and their importance in US production and world trade. In addition, a discussion of low resource production systems is included that is dominated by tilapia and carp culture systems. A brief overview of the principles of aquaculture production economics and management is presented followed by a review of economic studies.     

Book reviews

Public Policy and Agricultural Technology: Adversity Despite Achievement,Edited by Don F. Hadwiger & William P. Browne, 1987. Basingstoke, Macmillan Press, with Policy Studies Organization, ix+126 pp.

A Colour Atlas of Comparative Veterinary Haematology,By C. M. Hawkey & T. B. Dennett, 1989. 192 pp, illustrated. London, Wolfe Medical Publications. £40.00. ISBN 07234 09307.

A Stereotaxic Atlas of the Brain of the Chick (Gallus domesticus), By W. J.Kuenzel & M. Masson, 1988. 166 pp., illustrated. Baltimore, The Johns Hopkins University Press. £44.50. ISBN 0 8018 3700 6.     

C- AND G- BANDING PATTERNS AND CHROMOSOMAL MORPHOLOGY OF SOME BREEDS OF AUSTRALIAN CATTLE

A cytogenetical study using metaphase chromosomes from cultured lymphocytes, was made of 2 Banteng (Bibos banteng) steers and 218 bulls representing 13 purebreeds (Bos taurus type, Bos indicus type and Sanga) and 7 cross-breeds. Studies were made of photographic karyotypes of Giemsa stained and C-banded chromosomes of bulls of each breed and of B-banded chromosomes from 3 breeds of Bos indicus and one cross-breed Australian Friesian Sahiwal) cattle. The relative lengths of chromosomes of Bos taurus and Bos indicus bulls were compared and significant difference in relative lengths of the X chromosomes were noted between these two species. There was a differences in morphology of the Y chromosomes; Sanga, Banteng and Bos taurus type breeds had a small submetacentric Y chromosome, except for the Jersey which had a metacentric Y chromosome. All Bos indicus type bulls had an acrocentric Y chromosome but the Droughtmaster breed had two forms of the Y chromosome (submetacentric and acrocentric). The C-banding patterns of the autosomes and X chromosomes were similar for all breeds while those of the Y chromosomes of Bos indicus type cattle allowed their accurate identification. G-banding patterns of Bos indicus resembled those of Bos taurus and enabled pairing of homologous chromosomes. Centromeres of the autosomes were unstained but those of the sex chromosomes were darkly stained.