Search

Fisheries management must trade off biological conciseness with institutional and practical constraints, which may preclude separate management of all genetic stock units but should ensure long-term survival of such components in each area. The technique described here, while unable to explicitly identify genetic differences, is applicable to other species and would be particularly valuable for preliminary studies where limited resources preclude the use of expensive and analytically more complex techniques such as morphometric and meristic or electrophoretic analyses which are more suitable for that task. The method developed in this study involves the application of discriminant function and canonical variates analysis to information on size and age structure of Pacific herring (Clupea harengus pallasi) from samples representing the seven major migratory populations and other spawning aggregations in six geographical regions of coastal British Columbia. Results of the analysis quantify the separation of stocks of herring between geographical regions, and at a finer spatial scale, within all regions. Generally, one or more migratory stocks occurred together with minor stocks in each geographical region.

Genetic stock identification (GSI) studies usually assume that electrophoretic data from different laboratories are accurate, precise, and comparable. We compared the genetic scores from replicate (identical) collections of pink salmon (Oncorhynchus gorbuscha) tissues that were analyzed in a "blind" manner by three different laboratories; scores at 15 genetic systems (18 loci) were compared for 1248 fish. The scores from laboratories A and B consistently agreed. Their average discrepancy rate across all loci was 0.21%, which was approximately 18 times lower than the discrepancy rate of laboratory C (3.86%). Laboratory C also reported data with higher numbers of discrepancies (P

Relative growth rates of different genetic groups of common carp were tested simultaneously in cages stocked with a given genetic group (separate cages), and in cages stocked communally with samples of different genetic groups. The results of three tests are described. A clear association between relative growth of different progenies, in communal and separate testing, was found in one of these tests. The other two tests did not generate significant associations between relative growth in communal and separate cages, presumably as a result of an insufficient number of tested groups or of replications of separate cages. We suggest that, in cages, results from the convenient method of communal testing may serve as reliable predictors for relative growth of different genetic groups in separate testing. This should be confirmed in further, similar investigations. Previous tests in communally and separately stocked ponds generated a similar conclusion. On the other hand, genotype-environment interactions have been demonstrated when the same genetic groups were tested simultaneously in communal ponds and cages. This means that relative pond performance is not a reliable predictor for performance in cages, or vice versa. Cage culture is presently under consideration as a commercial production method for common carp. The investigations described here indicate that performance testing for choice of genetic stock for cage operations needs to be carried out in cages and not in ponds. Large scale production in cages is carried out, or planned, with several fish species. Genetic testing for these operations is carried out largely in communal cages. The methodology of this testing method been investigated only in common carp, by simultaneous testing of the same genetic groups in communal and separate cages.

Pallets of stocks derived from the North Central Randombred White Leghorn population without selection (C) or selected (S) on family performance when kept with beaks intact in multiple-hen cages were compared. Pullets had intact, one-fourth, or one-half of the beak removed (IN, 1/4R, and 1/2R, respectively). No stock differences were detected for behavior traits or other measures during the rearing period. However, beak-trimmed pullets were more inactive and feeding behavior was depressed in 1/2R pullets 1 wk after beak trimming. At 16 wk, 1/4R pullets' beaks had regrown but 1/2R pullets' beaks continued to be shorter than IN pullets' beaks. No differences in fearfulness were found between genetic stocks or among beak length treatments early in the laying period. Deaths from beak-inflicted injuries accumulated steadily from 18 wk until the study was ended at 40 wk. Cannibalistic deaths occurred less frequently in S as compared with C pullets within each beak treatment. As the amount of beak removal increased, beak-inflicted mortality decreased. The S pullets had earlier sexual maturity, lighter egg weights, and greater hen-housed egg production and egg mass than C pullets, and 1/2R pullets had greater egg production than 1/4R and IN pullets. Genetic stock by age and beak treatment by age interactions were present for hen-housed production and egg mass, and the interactions appeared to result primarily from increased mortality from cannibalistic pecking with increased age.

Stocks of northern largemouth bass Micropterus salmoides salmoides, Florida largemouth bass M. s. floridanus, and both reciprocal F1 hybrids were produced in Champaign, Illinois, with natural spawning techniques. The genetic composition of each of these stocks was confirmed electrophoretically. Overwinter survival of northern largemouth bass in central Illinois was significantly greater than that of Florida largemouth bass; the two reciprocal F1 hybrids had intermediate survival. The absolute survival rate of all stocks decreased as the severity of the winter increased; however, the effects were most dramatic for the Florida subspecies. The northern largemouth bass also exhibited-greater second- and third-year growth than the Florida largemouth bass; again, the reciprocal F1 hybrids were intermediate. Results of this study indicate the potential negative effects that may arise when Florida largemouth bass or hybrids between it and the northern subspecies are introduced into waters of the USA and ...

Genetic Analysis of Juvenile Chinook Salmon for inclusion in 'Ecology of Juvenile Salmonids in Shallow Tidal Freshwater Habitats in the Vicinity of the Sandy River Delta, lower Columbia River, 2007. Final report submitted to the Bonneville Power Administration, Contract DE-AC05-76RLO1830.' Genotypic data were collected for 108 Chinook salmon and used in the genetic stock identification analysis. Results of the mixture analysis are presented in Table 1. Percentage estimates for four genetic stock groups (West Cascade Tributary Fall, Willamette River Spring, Deschutes River Fall, and Upper Columbia River Summer/Fall) ranged from 11% to 43%, all with non-zero lower 95% confidence intervals. Small contributions were also estimated for the West Cascade Tributary Spring (3%) and Snake River Fall (6%) stock groups. Results of individual fish probability assignments were summed by collection date (Figure 1) and site (Figure 2). Assignment probabilities for the most likely stock group for each individual ranged from 0.51 to 1.00 with approximately 60% of the assignments greater than 0.90 (data not shown). Nearly all of the low probability assignments were fish with assignments split between the Deschutes River Fall and Upper Columbia River Summer/Fall groups.

Book description: Economics, Ethics, and Environmental Policy: Contested Choices offers a comprehensive analysis of the ethical problems associated with basing environmental policy on economic analysis, and ways to overcome these problems.

The genes involved in the putrescine formation by Morganella morganii were investigated because putrescine is an indicator of food process deterioration. We report here on the existence of a new gene for ornithine decarboxylase (ODC) in M. morganii. The sequenced 5,311-bp DNA region showed the presence of four complete and one partial open reading frame. Putative functions have been assigned to several gene products by sequence comparison with the proteins included in the databases. The third open reading frame (speC) encoded a 722-amino acid protein showing 70.9% identity to the M. morganii ODC previously characterized (SpeF). The speC gene has been expressed in Escherichia coli, resulting in ODC activity. The presence of a functional promoter (PspeC) located upstream of speC has been demonstrated. Quantitative real-time reverse transcription PCR assay was used to quantify expression of both M. morganii ODC-encoding genes, speC and speF, under different growth conditions. This assay allows us to identify SpeF as the inducible M. morganii ODC, since it was highly expressed in the presence of ornithine., This work was supported by grants AGL2005-00470 (Comisión Interministerial de Ciencia y Tecnología), FUN-C-FOOD Consolider 25506 (Ministerio de Educación), RM03-002 (Instituto Nacional de Investigación Agraria y Alimentaría), and S- 0505/AGR/000153 (Comunidad de Madrid). We thank the E. coli Genetic Stock Center for provide the E. coli HT414 (CGSC 6856) strain. The technical assistance of M. V. Santamaría is greatly appreciated. J.M. Landete is a recipient of a postdoctoral fellowship from the Ministerio de Educación.

This chapter describes some of the key steps taken during the development of the international agriculture research effort over the last century and presents an overview of the various players involved. The role and niche of foundations, the private sector, and national programs are discussed in the context of accessing and using genomics resources. A description of the Generation Challenge Programme (GCP) is presented as a detailed case study of an international initiative aiming to develop and utilize genomics resources to enable plant breeders in the developing world to produce better crop varieties for resource-poor farmers. The challenges faced by the international programs, and the GCP in particular, to positively impact crop productivity in marginal environments are discussed.

As maternal mammals entered the evolutionary scene, the unique responses of nursing conjoined with maternal care, audiovocal communication for maintaining mother–offspring contact, and play behavior became staples of the mammalian behavioral repertoire. The consideration of neuroeconomics and neural areas devoted to adaptive choices suggests that another unique aspect, that is, contextually appropriate efficient problem solving is also linked to the onset of maternal mammalian behavior. Thus, the earliest explorations of economic theories may have been conducted in the brains of these early mammals. This chapter provides convincing evidence that the maternal mammal offers unique opportunities to explore the dynamic mechanisms underlying altered response strategies in specific situations. As the female becomes pregnant, her “genetic stock” increases, which alters the ultimate consequences of her responses. Accordingly, adaptive responses have been observed in females with maternal experience. Although researchers have yet to investigate the effect of maternal experience on specific parietal areas such as the lateral intraparietal area implicated in primate decision making (i.e., the neuroeconomics of choice), it would be interesting to investigate this area in parous animals. Additionally, further investigations of enhanced neural networks accompanying each full maternal experience in the form of neural growth factors, morphological differences, increased synapses, more complex networking of dendritic and/or axonal processes, or even more elaborate scaffolding of glial cells will help to explain the cumulative benefits of each maternal experience. As the gains and costs of mammalian response options are continually calculated, at some point the costs outweigh the gains of providing nurturing responses toward the offspring—learning more about these parenting response thresholds will also offer insights into the neuroeconomics of the parental brain.

The effects of movable roosts, relationship of cage mates (siblings versus nonsiblings), and genetic stock on measures of behavior, production, and physical condition were investigated. Sibling and nonsibling pairs of hens derived from two male parental stocks (designated MPS1 and MPS2) were randomly assigned to two cage batteries (384 hens total). The batteries were identical except that the cages of one had individual wood roosts, which were automatically raised at night and lowered the next morning. The laying phase comprised 13 28-day periods. On the first 4 days of Periods 1, 3, 5, 7, 9, and 11, video recordings were made of 8 cages per day. Video-recorded data for Period 5 were discarded, however, because equipment failure caused an unplanned photoperiod ratio. Direct visual observations were carried out in Period 13. Egg production and feed consumption were recorded in each period. Feather scores were determined in Periods 3, 6, 9, and 12, and in Periods 6 and 13, hens were weighed and the number of lesions to the feet counted. Overall, roosts appeared to improve well-being. Resting occurred more in cages with roosts, feathering was better initially, body weights were slightly higher, and foot lesions were were fewer. Egg production was not affected except that egg cracks were more frequent in roosts cages. Relationship of cage mates had relatively little influence. However, in conventional cages, nonsiblings manifested more bobbing behavior, and in MPS1, nonsiblings had higher feed consumed per dozen eggs. Hens of MPS1 performed more head flicking, drinking, physical displacement, aggression, and cage wall climbing than MPS2 hens. They also had higher egg production, weaker egg shells, poorer feathering, and more lesions to the feet. The genetic stock differences suggest that hens of MPS1 experienced poorer well-being. None of the treatments significantly affected mortality.

Two experiments were conducted to compare the effects of cage and floor rearing of White Leghorn pullets on their subsequent behavior as late stage adolescents and adults when kept in multiple-hen cages. In Experiment 1, behavioral data were obtained on adolescent pullets and hens of a randombred experimental stock kept 7 per cage at 332 cm2 per bird. Cage-reared pullets stood, preened, moved, fed, and pecked inedible objects more but crouched less than floor-reared pullets during Days 1 to 3 posthousing. However, differences were not found for those traits at 30 and 57 wk of age. In Experiment 2, floor- and cage-reared layers of two commercial stocks, kept 4 per cage at 348 and 464 cm2 per bird, were used to obtain behavioral data at 33 and 60 wk of age. At those ages, the only rearing environment effect found was more pecking of inedible objects by cage-reared pullets than by floor-reared pullets. Interactions of rearing environment with genetic stock, density, and age were generally absent.

Spawning lake whitefish in Lake Winnipeg from Dauphin River–Lake St. Martin, Traverse Bay, Berens River–Poplar River–Big Black River and Grand Rapids and in Little Playgreen Lake are accorded subpopulation status based on morphometric measurements, meristic counts, and differences in frequencies of alleles at the muscle glycerol-3-phosphate dehydrogenase (g-3-pdh-b) locus. The frequency of the g-3-pdh-b-3 allele in samples from Dauphin River–Lake St. Martin was 0.77 compared with 0.46 for whitefish from the remainder of Lake Winnipeg and Little Playgreen Lake. Two loci for isocitrate dehydrogenase and one lactate dehydrogenase locus are also polymorphic in these fish but no significant allele frequency differences were found at these loci among the samples of spawners compared above. Hatchery-reared lake whitefish, obtained from stock in Clearwater Lake and William Lake and planted as fry or eyed eggs in Lake Winnipeg at Dauphin River and Grand Rapids, do not appear to have made a detectable genetic contribution to the local whitefish stocks, based on differences in g-3-pdh-b and idh Bβ allele frequencies among parent stock and spawners captured near the release sites.

Four experiments were conducted to compare productivity, nervousness, feather condition, and livability of cage- and floor-reared White Leghorn layers when kept as adults in several environments. In Experiment 1, productivity and livability data were obtained on layers of an experimental stock kept 7 per cage at 332 cm2 per bird. Age at first egg of cage-reared birds was 5.3 days younger than that of floor-reared birds. In Experiments 2 and 3, layers of three experimental stocks were kept 6 per cage at 387 cm2 per bird (Experiment 2) or 20 per floor pen at 1,800 cm2 per bird (Experiment 3). In general rearing environment effects and interactions of rearing environments with genetic stock and ages were absent for productivity traits and mortality of hens kept in either cages or floor pens. Floor- and cage-reared layers of three commercial stocks, kept 4 per cage at 348,464, and 580 cm2 per bird, were compared in Experiment 4. Cage-reared hens had better feather coverage than floor-reared ones at 57 to 60 wk of age. Rearing environment by genetic stock or by density interactions were generally absent. A negative correlation (r = −.4) was found between nervousness score and feather score. It was concluded that pullets reared in either cages or floor pens should be able to adapt equally well to multiple-bird cages or low-density floor pens as adults.

Measures of the utility of loci in genetic stock identification problems are usually not based on the method of maximum likelihood, which is the actual statistical procedure used to estimate stock contributions. We present a general procedure, derived from the likelihood method, for assessing the utility of baseline data. The method depends on the curvatures of potential likelihood surfaces and can be used prior to mixture sampling. We also develop a real time implementation of a curvature measure and apply it to simulated mixture samples. The error in likelihood estimation depends on the amount of variation in genotype frequencies between reference samples as well as the location of the center of that variation. The curvature measure accounts appropriately for both factors and, in addition, is able to quantify the synergistic interaction of multiple loci. The curvature approach and simulation results are also applied to the problem of sampling allocation.

A true breeding mutant having free corolla lobes, designated as polypetalous mutant was obtained in sesame (Sesamum indicum Linn.), after irradiating seeds of cv N62-32 with 1·6 kr fast neutrons. The inheritance pattern indicated that the polypetalous corolla is monogenic recessive to the gamopetalous corolla characteristic of sesame and the family Pedaliaceae. After crossing to another induced mutant having gamopetalous corolla with a band of pink coloured dots, a genetic stock with two recessive markers was isolated.

The relative costs and benefits of genetic stock collections and germ plasm collections are discussed. The status of national and international collections is compared with the needs of plant breeders and geneticists. There is an international need for germ plasm systems that emphasize the use and employment of materials rather than acquisition and storage. For base collections to function, they must provide for regeneration, characterization, documentation, and evaluation of their materials. The quality of a germ plasm system should be judged on the basis of the quality of the materials available to scientists. Adequate quantities of high-quality seed that are of known provenience, spanning the range of known genetic diversity, promptly delivered, and well described constitute the minimum that should be expected. All too often such minimal requirements are not met.

Seven countries participated in the 3-year programme (1986–1988) of the Willow Breeding Activity, Task 2 of the International Energy Agency's Bioenergy Agreement. The objectives of the activity were to facilitate the development of superior, high yielding willow clones for energy plantations by (a) exchange of genetic stock, (b) exchange of information on breeding studies, and (c) joint actions. The results of this cooperative activity are discussed accordingly. Significant achievements are in (a) enrichment of the genetic stock, especially of North American willow species; (b) evaluation and stimulation of genetic studies and breeding programmes; and (c) joint actions on disease surveys, clonal identification problems, joint testing methods and willow feedstock qualities for energy conversion. The development of high yielding stock (30 odt/ha per year or more) seems to be within reach.

Removal of half of the upper and less of the lower beak of pullet chicks at 4 weeks of age resulted in less pecking at feed, fewer non-agonistic pecks of all kinds, less moving and preening, and more inactive standing and crouching during the following 3 weeks. Escape and avoidance behavior did not differ for 8–9-week-old, intact-beak and trimmed-beak pullets. Body weights, used as indirect indicators of feed intake, were initially suppressed following beak treatment, but trimmed-beak pullets were only marginally lighter by 27 weeks of age. Beak length measures taken 3 months after beak trimming indicated that regrowth had not occurred. Beak trimming was highly beneficial in reducing beak-inflicted feather loss and mortality from cannibalistic pecking in two of three commercial genetic stocks. Pullets of the third stock suffered no greater feather loss when their beaks were left intact than when they were trimmed, and mortality from cannibalistic pecking was essentially absent in this stock, regardless of beak treatment. These results indicate that either no beak trimming or less severe beak trimming is a practical possibility for poultry producers, as soon as appropriate genetic stocks are identified.

To date, only a few studies have reported successful manipulations of Peromyscus embryogenesis or reproductive biology. Together with the Peromyscus Genetic Stock Center (http://stkctr.biol.sc.edu), we are characterizing the salient differences needed to develop this system. A primary goal has been to optimize oocyte/early embryo retrieval.

Eugenics, the attempt to influence human breeding in the collective to ‘better’ human genetic stock, was popular between 1890 and 1938 in both the United States and Europe. Latent and subtle elements of eugenic thinking still persist in genetic screening and testing, and in genetic-marker profiles of criminal suspects in forensic science. Keywords: eugenics; human betterment; genetic screening

A newly developed DNA microarray was applied to identify mitochondrial (mt) DNA haplotypes of more than 2200 chum salmon in the Bering Sea and North Pacific Ocean in September 2002 and also 2003, when the majority of maturing fish were migrating toward their natal river. The distribution of haplotypes occurring in Asian and North American fish in the surveyed area was similar in the 2 years. A conditional maximum likelihood method for estimation of stock compositions indicated that the Japanese stocks were distributed mainly in the north central Bering Sea, whereas the Russian stocks were mainly in the western Bering Sea. The North American stocks were abundant in the North Pacific Ocean around the Aleutian Islands. These results indicate that the Asian and North American stocks of chum salmon are nonrandomly distributed in the Bering Sea and the North Pacific Ocean, and further the oligonuleotide DNA microarray developed by us has a high potential for identification of stocks among mixed ocean aggregates of high-seas chum salmon.

Publisher Summary Fisheries, water diversions, and other environmental shifts have the potential to result in significant loss of specific fish stocks, necessitating careful management wherever possible. Impacts often affect complex mixtures of different stocks, however, making effective management critically dependent on precise methods for stock identification. This is particularly important in contexts involving threatened and endangered species because conservation measures require focused targeting in order to achieve and monitor rebuilding goals. As a result, the application of genetic and statistical methods toward stock identification has continued to develop and improve in the past few decades, largely in response to a number of new challenges. These fall into three primary areas: continued interest in sustaining harvest and economic yield despite extreme variability and changes in habitat availability, ocean productivity, stock strengths, and effectiveness of fishing technologies; increasing interaction between farmed and hatchery-reared fish with their counterparts from wild populations;the increasing number of endangered or threatened species cases needing special attention for protection and rebuilding. Cases are selected to span major regions around the Northern Pacific Rim but also for their unique contributions to the field of genetic stock identification (GSI).

Atmospheric ammonia inhibits broiler performance. Quantified effects are based on older genetic stock with a BW of 2000 g at 7 wk. In contrast, modern genetic stock reaches 3200 g at 7 wk of age. To assess the impact on present day broilers, 2 trials were conducted exposing male broilers to graded levels (0, 25, 50, and 75 ppm) of aerial ammonia from 0 to 4 wk of age. Sixty, 1-d-old chicks were placed in environmentally controlled chambers, weighed weekly as a group, and processed with yield determined at 7 wk of age. Final BW was significantly depressed by 6 and 9% for the 50 and 75 ppm concentrations of ammonia as compared with 0 ppm. Also, mortality was significantly greater at the 75 ppm ammonia concentration, 13.9% compared with 5.8% for the 0 ppm treatment. Percentage yield of deboned meat per bird decreased slightly with increasing exposure to ammonia but was not statistically significant. Although current genetic stock reaches growout weights that are approximately 60% greater than those 2 decades ago, the relative quantified effects of ammonia exposure were similar. Additionally, statistical analysis of the results provided a simple equation, presented herein, for predicting the decline in BW of male broilers after exposure to ammonia.

A conference on ``Aquaria Fish Models of Human Disease'' was held September 20–23, 2000, at Southwest Texas State University, San Marcos, Texas, USA. The meeting was sponsored by the National Cancer Institute (National Institutes of Health), the Roy and Joan Mitte Foundation, and Southwest Texas State University, home of the Xiphophorus Genetic Stock Center. In conjunction with the meeting, the conference organizers asked several participants to describe those components of their research programs that provide services and information to other researchers. This article summarizes their responses.

At least 19 single recessive gene yellow leaf mutants and one duplicate recessive gene mutant have been described in soybean. This study was conducted to associate a yellow leaf mutant, y10, with a specific soybean chromosome by using primary trisomics (2n = 41). Seven soybean primary trisomics were hybridized as female parent with genetic stock strain, T161, carrying y10. F(1) disomic and primary trisomic plants were identified cytologically. One disomic (control) and all primary trisomic plants were allowed to self-pollinate and F(2) populations were classified for green versus yellow leaf mutant. The F(2) population of Triplo 3 segregated in a 17:1 ratio, while a disomic (3:1) ratio was observed with Triplo 8-, 17-, 18-, and 20-derived F(2) populations, suggesting that the y10 locus is on chromosome 3. The y10 locus was examined with four simple sequence repeat (SSR) markers (Satt584, Sat_033, Satt387, and Satt022) from molecular linkage group (MLG) N and y10 was found linked with Satt022. Therefore we confirmed the association of MLG N with chromosome 3. The possible association of y10 with Triplo 16 and Triplo 19 are discussed.

The spectacular increase in broiler consumption from the 1930s to now is almost a straight line. Improvements in nutrition information, better genetic stock that considers consumers' preferences, good nutritional values, industrial innovations, and the Chicken of Tomorrow Contest have all contributed to providing a lot of healthy chicken to the consumers.

Belugas ( Delphinapterus leucas ) harvested from communities on the eastern Hudson Bay (EHB) arc, Sanikiluaq on the Belcher Islands, northwestern Quebec, Hudson Strait, neighboring areas of Hudson Bay, and the St. Lawrence were characterized by differences in the mitochondrial DNA (mtDNA) d-loop sequence and in 15 nuclear microsatellite loci. Results supported the hypothesis that communities outside the EHB arc hunt some EHB belugas, which were strongly differentiated from all neighboring sample populations by mtDNA haplotypes and weakly differentiated by microsatellite data. Belugas genetically most similar to those sampled in EHB comprised 19% of the harvest in Hudson Strait and Ungava, 15% in northwestern Quebec, 9% in western and northern Hudson Bay, 8% in Sanikiluaq, and 5% in Kimmirut (though many were possibly not belugas from EHB, but uncommon genotypes in other stocks). Within EHB, belugas from the Nastapoka River (1984-95) and elsewhere on the EHB arc (1993-97) were very similar. Using simple probabilistic calculations to assign individuals to their most likely sample population, we estimated that 15% of belugas hunted in EHB could be from northern or western Hudson Bay and 3% from Sanikiluaq. St. Lawrence River belugas were strongly differentiated from all other sample populations by both haplotypes and microsatellites. Stocks in Arctic populations were identified by different proportions of alleles and by genetic consistency over several years. Belugas from Sanikiluaq, Kimmirut, and EHB may represent three separate stocks, while large genetic diversities in northern Quebec, northern Hudson Bay, and Arviat confirm that mixtures of stocks were harvested in these areas.

With the world human population touching roughly 7 billion by the turn of the century, malnutrition and undernutrition are increasing alarmingly along with food shortages Animal products such as milk, meat and eggs can provide supplementary food of high nutritive value. Hence, intensification of animal production is important. This has been achieved in the developed world (North America and Europe) through several biotechnological innovations such as use of improved genetic stock, better livestock management, improvement in the nutritive value of animal feed and feed conversion efficiency (Orskov, 1993; Perry, 1995). However, in many developing and underdeveloped countries of Asia, inadequate supply of good quality feed is the main factor hindering the intensification of animal production (Ibrahim & Schiere, 1987). According to Devendra (1988), many of the feed resources in South Asia include non-conventional feed resources, crop residues and agro-industrial by-products and are currently designated as wastes.

The numerous accessions stored in gene banks are in many respects a haphazard sample of both the man-made variation found in breeding lines, landraces and genetic stocks, and of the natural variation found in the related wild species. The main reason for the discrepancy between the stored and the actual variation is the fact that the material is only rarely sampled with any clear objective in mind other than simple storage of actual or potential breeding material. Rarely, if ever, has sampling been done according to a predefined strategy and with a specific scientific purpose in mind. This makes the strategies for screening germplasm widely different from the strategies used in more traditional projects (1). Hence, finding only a few accessions carrying resistance genes may be worth the effort almost irrespective of how many accessions have to be screened (to find 23 accessions of cultivated rice (Oryza sativa) resistant to the striped stem borer (Chilo suppressalis) it was necessary to screen 22 920 accessions (2)). The purposes for screening germplasm may be varied, however, just as may be the size, structure, and content of the collections to be screened. For example, a gene bank manager may, for purely economic reasons, screen a collection in order to eliminate duplicates, or in order to assess the level of diversity, whereas a breeder may wish to screen for useful agronomic traits. The choice of the most appropriate methodology is the subject of several considerations, most importantly, the actual problem at hand and the available time and money. A helpful and indispensable invention for accessing very large collections is the core collection (see below), which is being developed for many major crops.

Few would disagree that immunization to prevent infectious diseases has significantly impacted the economics of livestock and poultry production globally. Unfortunately, even with these successes, there is a need to extend the impact of such vaccination programs since economic losses continue to plaque producers and in some instances limit the areas of livestock production or reduce the economic return to producers by limiting the export of genetic stock. To increase animal productivity, infectious diseases have been the primary targets for vaccination, although more recently, ectoparasites are also becoming a target for immunization.

Chickens from three genetic stocks known to differ in growth potential consumed ad libitum either a single (control) diet or a choice of two diets that differed in protein and energy. Formulation of the choice diets was such that when mixed in specific proportions they provided single diets that decreased in protein and increased in energy over the experimental period. When comparisons of feeding regimens were made at a common age, body weights and feed efficiencies for all stocks were enhanced in chicks fed a single diet. When comparisons were made at a common body weight for controls, chickens fed the single diet were about 15% heavier than those given a dietary choice. For feed efficiency, however, the pattern remained for the faster growing stock whereas there was no difference between feeding regimens for the slower growing stock. Chicks provided a choice of diets had heavier abdominal fat pads and lighter breasts relative to body weight than those fed a single diet. With choice feeding, there were stock by diet interactions for dietary preferences through the first 9 d after hatch. Early on, the interactions resulted from the faster growing stocks exhibiting a greater preference for the diet higher in protein and lower in energy than the slower growing stock. By Day 5, however, the interaction occurred because stocks exhibited either no dietary preference or preferred the diet that was lower in protein and higher in energy. Regardless of genetic stock, at 9 d of age and thereafter there was a clear preference for the diet lower in protein and higher in energy than the diet higher in protein and lower in energy. These data for feed intake were consistent with behavioral observations that showed a preponderance of chicks eating from the feeder containing the diet lower in protein and higher in energy. Compared to a single diet, under choice feeding, energy utilization was negatively influenced more in the faster than slower growing stocks. Protein and sulfur amino acid utilization was not affected by feeding regimen in faster growing stocks, but was enhanced under choice feeding in the slower growing stock. Although lysine utilization was enhanced by choice feeding in all stocks, the effect was greater in the slower than in the faster growing ones. These data demonstrate that although broiler diets are formulated to enhance growth and overall feed efficiency, chicks that are provided a dietary choice of protein and energy do not eat to maximize growth or feed efficiency.

This final report of the 3-year study summarizes activities and results for 1993. Study objectives were to: (1) determine the source of losses (or accounting errors) for adult chinook salmon between Ice Harbor Dam (IHR) and Lower Granite Dam (LGR), and upstream of LGR in the Snake River; (2) identify spawning locations upstream of LGR for calibration of aerial redd surveys, redd habitat mapping, carcass recovery for genetic stock profile analysis, and correction of estimated adult/redd ratios; and (3) estimate passage and migration times at Snake River. 200 fall chinook salmon were radio tagged and tracked with aerial, fixed-site, and ground mobile tracking. Fish were released upstream of IHR at Charbonneau Park (CHAR). 190 of the fish were tracked or relocated away from CHAR. 59 fish descended to below IHR without crossing Lower Monumental Dam (LMO). Another 128 salmon passed upstream of LMO without falling back at IHR. Only 80 salmon passed Little Goose Dam (LGO) without falling back at a downstream dam; 66 of these fish passed LGR. Many fish that fell back reascended the dams. A total of 72 salmon released at CHAR passed upstream of LGR, including fish that had fallen back and reascended a dam. Overmore » 80 percent of the salmon that entered Lyons Ferry Hatchery each year had reached LGO before descending to the hatchery. Extensive wandering was documented between LMO and upstream of LGR before salmon entered Lyons Ferry Hatchery or the Tucannon River. In 1993, 41 salmon were found to be of hatchery origin when recovered. These fish entered Lyons Ferry Hatchery with similar movements to unmarked salmon. Each year a few salmon have remained near the hatchery without entering, which suggests the hatchery may have inadequate attraction flows. Fall chinook passed lower Snake River dams in 2-5 days each on average. Median travel times through LMO and LGO were 1.0-1.3 days each, which was slower than for spring chinook or steelhead in 1993. 5 refs., 21 figs., 20 tabs.« less

SummaryThe switch from keeping laying hens in a floor or free range system into a cage system led to a considerable change in the way that breeding and selection took place. In the past 40–50 years up to the present date, the increase in genetic improvement of the egg laying trait was substantial. However, cage-adapted populations of laying hens seem to have lost some of their abilities to an adequate performance when returned to the old floor\free range systems. The strong concentration of all parts of the poultry production has meant that less than 10 international breeding companies supply most hens for laying purposes in the world and they have very little interest in developing genetic material for the West-European region where there are marked consumer preferences for eggs produced in non-cage systems. A particular Danish line, of White Leghorn origin named “The Skalborg hen” seems to have survived during an era of cage production system and they seems to have a production potential at farm level.

A selected line of White Leghorns that has shown improved survivability and productivity and reduced feather loss in multiple-hen cages was evaluated for hematological and adrenal responses under both stressed and unstressed conditions. It was hypothesized that hens selected for adaptation to multiple-bird cages would react less intensely to stressors. Three lines of chickens (selected, control, and commercial) were housed in either single-hen (1 hen) or multiple-hen cages (12 hens, social competition) at 16.7 or 17.1 wk of age. They were subsequently subjected to cold exposure at 33 wk of age and heat exposure at 44 wk of age. Genetic stock as a main effect, and the interaction of genetic stock with either a cold or heated environment or with cage size, had no effect on plasma levels of cholesterol and corticosterone. At the time of transfer to laying cages, the selected line of pullets, as indicated by a decrease in packed cell volume, appeared to adapt more quickly to the new waterer system of multiple-hen cages than did the control and commercial lines. At 33 wk of age, the control and commercial lines in multiple-hen cages experienced heterophilia and increased heterophil to lymphocyte ratios, whereas the selected line did not, when compared with these same lines in single-hen cages. This leucocytic response could be interpreted to mean that the selected line of chickens adapted better to social competition than either the control or commercial lines; however, a similar leucocytic response was not observed at 18 or 44 wk of age. In conclusion, the physiological characterization of the selected line of Leghorns showed evidence of improved adaptation to multiple-hen cages when compared to the other stocks. In some cases, the selected line responded less intensely to stress; however, trends were not always consistent.