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PubMed1987

[Endangered domestic animal breeds in German-speaking countries. IV. Swine and goats].

In contrary to the past in the German speaking countries there are now only eight pig breeds that are kept for meat. There are evident reasons for the reduction to mainly four breeds, especially if one looks to the actual habitudes of the consumer. By a decision of the administration in 1927 there exist only two native goat breeds in West Germany. In Switzerland, goat breeding has always had a great importance. Here there are not only many more goats than in West Germany, but with eight breeds the number of different types is much greater. Four pig breeds and six goat breeds are described. All have only local meaning and importance and all are endangered.

Animal Husbandry↗

PubMed1979

[Dog breeding in the Netherlands (author's transl)].

The present report is a review of the history of dog breeding and of the current status of breeding dogs in the Netherlands. Breeds of dogs were previously subjected to methods of breeding in which survival and reproduction of the animals depended on the usefulness of dogs for various duties. Today, animals of these breeds are mainly kept as pets. Although serious breeders try hard to preserve the original characteristics of the animals, the breeds are nowadays subjected to strong forces of fashion and the pressure of public opinion. A marked increase in interest in special breeds is resulting in a reduction of the pressure of selection and thus in a wide variety of undesirable traits. In the opinion of the present author improvement of knowledge and in the understanding of dogs provides the best weapon to combat these unwanted effects.

Animals↗

PubMed1997

Prevalence and inheritance of and selection for hip dysplasia in seven breeds of dogs in Sweden and benefit: cost analysis of a screening and control program.

OBJECTIVE: To determine the prevalence and changes over time in the prevalence of hip dysplasia; to ascertain whether prevalence or severity of hip dysplasia was associated with sex of the dogs, age at which coxofemoral joint status was evaluated, or ancestral background; to determine the effects of selective breeding; and to conduct an economic evaluation of the hip dysplasia program operated by the Swedish Kennel Club. DESIGN: Analysis of radiographic evaluations of coxofemoral joint conformity. ANIMALS: 83,229 dogs from 7 breeds registered by the Swedish Kennel Club. PROCEDURE: All radiographs were scrutinized by a single radiologist (LA), and coxofemoral joint conformation was classified as normal or dysplastic, with the degree of dysplasia classified as 1,2,3, or 4. RESULTS: Decreasing prevalence of hip dysplasia corresponding to selection of breeding stock and high heritabilities was found. Sex differences were documented in 3 of the breeds. This was interpreted as breed differences in the distribution of genes related to hip dysplasia. Economic analyses showed that costs of screening and registration of coxofemoral joints was less than the value of dogs estimated to have been saved from moderate, severe, or very severe hip dysplasia in 6 of the breeds. CLINICAL IMPLICATIONS: Documented effects of age suggest that all dogs should be screened at the same age, rather than screening a few dogs at an older, more revealing age. In screening and control programs based on an open registry with access to family records, decreasing prevalence of hip dysplasia can be expected, and related to selection of breeding stock.

Age Distribution↗

PubMed1999

Prospecting enhances breeding success of first-time breeders in the great cormorant, Phalacrocorax carbo sinensis.

In many species of colonial seabirds, young birds visit colonies in the years before they start breeding. This prospecting behaviour may allow them to obtain information that could enhance their future breeding success. We examined the reproductive consequences of prospecting behaviour in the colonial great cormorant, and found support for this idea. New breeders that had been prospecting actively in the previous year obtained breeding sites of higher quality (i.e. closer to sites where conspecifics had fledged young in the previous year) and had higher breeding success than those that had been less active. Prospecting occurred mostly late in the breeding season, and coincided with the time when the majority of the eggs had hatched but before the chicks started fledging, that is, when breeding success in the colony reflected habitat suitability. These results are thus consistent with the use of conspecific reproductive performance as a cue for the quality of a breeding habitat as expected from the 'performance-based conspecific attraction hypothesis'. Copyright 1999 The Association for the Study of Animal Behaviour.

Journal Article↗

PubMed2000

Ecological constraints, life history traits and the evolution of cooperative breeding.

The ecological constraints hypothesis is widely accepted as an explanation for the evolution of delayed dispersal in cooperatively breeding birds. Intraspecific studies offer the strongest support. Observational studies have demonstrated a positive association between the severity of ecological constraints and the prevalence of cooperation, and experimental studies in which constraints on independent breeding were relaxed resulted in helpers moving to adopt the vacant breeding opportunities. However, this hypothesis has proved less successful in explaining why cooperative breeding has evolved in some species or lineages but not in others. Comparative studies have failed to identify ecological factors that differ consistently between cooperative and noncooperative species. The life history hypothesis, which emphasizes the role of life history traits in the evolution of cooperative breeding, offers a solution to this difficulty. A recent analysis showed that low adult mortality and low dispersal predisposed certain lineages to show cooperative behaviour, given the right ecological conditions. This represents an important advance, not least by offering an explanation for the patchy phylogenetic distribution of cooperative breeding. We discuss the complementary nature of these two hypotheses and suggest that rather than regarding life history traits as predisposing and ecological factors as facilitating cooperation, they are more likely to act in concert. While acknowledging that different cooperative systems may be a consequence of different selective pressures, we suggest that to identify the key differences between cooperative and noncooperative species, a broad constraints hypothesis that incorporates ecological and life history traits in a single measure of 'turnover of breeding opportunities' may provide the most promising avenue for future comparative studies. Copyright 2000 The Association for the Study of Animal Behaviour.

Journal Article↗

PubMed2001

Ecological factors underlying the adrenocortical response to capture stress in arctic-breeding shorebirds.

Birds breeding in the Arctic must carefully balance survival and reproduction because of the often extreme environmental conditions and the very brief breeding season. Acute elevation of plasma corticosterone is one mechanism that birds apparently use to alter the balance in favor of survival at the expense of reproduction when faced with stressors such as storms, predators, or low food availability. To examine this relationship, we applied a standardized stressor, capture and handling, to four species of shorebirds (Scolopacidae) during their breeding season in the Arctic and measured the increase in corticosterone between 3 min and 30 min after capture (hereafter called the stress response). We tested two hypotheses in an effort to explain the individual variation observed in the stress response. The first hypothesis states that individuals most responsible for parental care have a lower stress response than individuals less responsible for parental care. In species with uniparental care (Pectoral Sandpiper Calidris melanotos, Red Phalarope Phalaropus fulicaria), the caregivers had a lower stress response than the opposite sex, although in the latter species the difference was not significant (P = 0.016 and P = 0.102, respectively). In a species with equal biparental care (Semipalmated Sandpiper C. pusilla), the stress response did not differ between the sexes (P = 0.99, Barrow population). In a species with unequal biparental care (Western Sandpiper C. mauri), the more parental sex (males) had a much lower stress response than the less parental sex (P = 0.002). The second hypothesis states that individuals breeding in the high Arctic have a lower stress response than individuals breeding in the low Arctic. The stress response in a low-Arctic population of Semipalmated Sandpipers (Nome) was higher than that in a high-Arctic population (Barrow, P < 0.05). Individuals at an additional high-Arctic location (Prudhoe Bay) exhibited stress responses most similar to those of the Barrow population (P > 0.05). Taken together, these results provide evidence of a mechanism that birds may use to breed in environments with a brief breeding season and under conditions that might be perceived as stressful, if not for their reduced sensitivity to potential stressors.

Adrenal Cortex↗

PubMed1979

Amino acid sequence differences in pancreatic ribonucleases from water buffalo breeds from Indonesia and Italy.

The amino acid sequences of the pancreatic ribonucleases from river-breed water buffaloes from Italy and swamp-breed water buffaloes from Indonesia differ at three positions. One of the differences involves a replacement of asparagine-34, with covalently attached carbohydrate on all molecules, in the river-breed enzyme by serine in the swamp-breed enzyme. The ribonuclease content of the pancreas differs considerably between breeds and is lower in river buffaloes. A ribonuclease preparation from two swamp buffaloes contained a minor glycosylated component. Preliminary evidence was obtained that the amino acid sequence of this component has factors in common with the main component of the swamp-breed ribonuclease and with the river-breed enzyme.

Amino Acid Sequence↗

PubMed1982

The effect of environmental temperature on sebum composition of tropical and temperate breeds of cattle.

This study compared to effect of environmental temperature on sebum composition in 2 breeds of cattle, British (SH) and Brahman (GB), which differ in their abilities to tolerate heat. By long-term exposure of both breeds to environmental temperatures of 24 C and 32 C and the more heat-tolerant GB breed to 38 C, it was possible to make breed comparisons at (a) different body temperatures, i.e., when all animals were exposed to the same environmental temperature, and (b), at the same body temperature, i.e., when the 2 breeds were exposed to different ambient temperatures. The composition of sebum excreted to saturation level on the skin surface was determined. At the same body temperatures, the amounts of fatty acids in each lipid class were higher in GB than in SH animals except during hyperthermia when the amounts of triglyceride fatty acids were similar in both breeds. The total amounts of individual fatty acids except 14:1, 16:1, 20:0 and 14:OH were higher in both breeds at 32 C than at 24 C. The GB cattle excreted more essential fatty acids (EFA) than the SH cattle at 24 C and at 32 C. There was a significant genotype by environment interaction in the amount of EFA excreted in triglyceride decreased whereas the amount excreted in wax esters increased with rising body temperature.

Animals↗

PubMed1985

The effect of selective breeding on the development of coronary atherosclerosis in WHHL rabbits. An animal model for familial hypercholesterolemia.

To increase the incidence of coronary atherosclerosis in Watanabe heritable hyperlipidemic (WHHL) rabbits, an animal model for familial hypercholesterolemia, selective breeding has been carried out. The results obtained are as follows: The incidence of coronary atherosclerosis before selective breeding was 21.8%, whereas that after the breeding was 58.9% (average values for rabbits between 4 and 12 months old), showing that the incidence of coronary atherosclerosis can be increased by an appropriate breeding technique. With respect to the relationships between parents and offspring, if parents had coronary atherosclerosis, then the incidence of the disease in the offspring was 83.3%; therefore the disease was strongly heritable. The mean total cholesterol (TC) and triglyceride (TG) levels of the colony before selective breeding were 579 +/- 163 mg/dl and 471 +/- 144 mg/dl, respectively, while those after the breeding were 665 +/- 151 mg/dl and 603 +/- 178 mg/dl; serum lipid levels increased in parallel with incidence of coronary atherosclerosis. The earliest development of coronary atherosclerosis in the colony after selective breeding was found in 4-month-old rabbits and the whole colony suffered from the disease at 18 months of age.

Animal Husbandry↗

PubMed1980

Breed-specific dog hypersensitivity in humans.

The contribution of allergenic components of dander and serum from individual dog breeds in human hypersensitivity and the different responses to the various breeds in vivo and in vitro were examined. Differences in IgE antibodies directed against 13 individual dog breed danders and five different breed-specific sera were measured in groups sensitive and nonsensitive to dogs by the radioallergosorbent test (RAST). Cross-reactivity between dander extracts and sera was examined by RAST inhibition. Mean RAST binding to dog danders and sera was 15.9% and 14%, respectively, for the dog-sensitive group versus 0.6% for both danders and sera in the nonsensitive group. The mean difference in binding between groups was statistically different for all dander extracts and sera. The variances in binding were statistically greater for danders than sera in six of eight dog-reactive subjects. RAST binding and intradermal skin tests at a 1:10,000 w/v dilution correlated well (p < 0.05) for seven of nine breed-specific extracts. RAST inhibition studies showed that dog serum proteins were relatively poor inhibitors of dander extracts, and vice versa. Variability of skin test and RAST responses to different dog breed dander extracts support the existence of breed-specific allergens.

Animals↗

PubMed1985

Prefreezing and post-thaw semen characteristics of five ram breeds collected by electroejaculation.

Rams representing five breeds were electroejaculated twice weekly, during a three-week collection period. Ejaculates were evaluated for volume and concentration before freezing and for rate of motility and percentages of motile and abnormal cells both before and after freezing. Interactions between breed and collection period were evident (P<0.05) for semen volume and post-thaw values for rate of motility and percentage motile cells. Breeds differed (P<0.05) in these traits during some periods. In contrast, pre-freezing observations of rate of motility, percentage motile and abnormal cells and post-thaw percentage abnormal cells did not differ (P>0.15) among breeds. Sperm concentration per ejaculate tended to vary (P=0.11) among breeds. Semen characteristics frequently varied across collection periods. Rams within a breed differed (P<0.01) in all semen traits except post-thaw rate of motility and percentage motile cells. Semen was negatively affected by the freezing and thawing procedure. Ram within a breed and ejaculate within ram should be considered when selecting electroejaculated semen for freezing and subsequent use in artificial insemination.

Journal Article↗

PubMed1988

Influence of Synchro-Mate-B and breed composition on estrous response and pregnancy rate in spring- and fall-bred Brahman crossbred beef cows.

Estrous response, pregnancy rate, and the relationship between palpable corpora lutea (CL) and plasma progesterone concentrations were studied during the spring (n = 149) and fall (n = 146) breeding seasons using postpartum, crossbred beef cows consisting of 0-Brahman, 1 4 - Brahman , or 1 2 Brahman breeding. At the start of each breeding season, a jugular blood sample was collected for progesterone analysis; each cow was palpated for the presence of a CL and randomly alloted within breed to a non-treated control or Synchro-Mate-B (SMB) treatment. Fewer (P<0.01) fall than spring bred cows exhibited estrus within the first 21 d of breeding. Within 48 h of implant removal, 84 and 64% (spring and fall, respectively) of synchronized cows exhibited estrus. In both seasons, more SMB than control cows became pregnant by 7 d of breeding. Percentage of Brahman breeding did not influence estrous response or pregnancy rate. On the basis of 292 evaluations, palpation per rectum correctly assessed ovarian status 74% of the time. These data indicate that although season can influence response. SMB can be used effectively to synchronize Brahman crossbred cows. In addition, it was found that there is a close relationship between palpation per rectum and plasma concentrations of progesterone.

Journal Article↗

PubMed1992

A review of the likely causal pathways relating the reduced density of breeding dippers Cinclus cinclus to the acidification of upland streams.

Previous work has shown that the breeding density of a bird characteristic of upland streams, the dipper Cinclus cinclus, is markedly reduced at low pH in both Wales and Scotland. Populations also declined when streams became more acidic. Evidence of causal explanation for these relationships is that: (1) Food quantity is reduced in acidic streams, and important prey, including those rich in calcium, are scarce; (2) Blood chemistry in pre-breeding birds differs between acid and circumneutral streams, with plasma calcium reduced in those breeding at low pH. Skeletal sources of calcium are probably limited; (3) The time spent foraging by pre-breeding birds on acidic streams is markedly increased, even though overall energy costs on acidic and circumneutral streams are similar. Body condition is inferior to birds on circumneutral streams; (4) Egg laying is significantly delayed on acidic streams irrespective of an effect on laying of altitude, and clutch and brood sizes are significantly reduced; (5) Eggs are lighter and shells thinner at low pH; (6) Chick growth is reduced at low pH; (7) Contamination by heavy metals and persistent organochlorines is low in the populations on acidic streams and cannot explain the impaired breeding performance. None of these features can exclude the possibilities that acidic streams either hold populations of poor quality birds, which show the above features, or that acidity affects the breeding ecology of all dippers that attempt to breed at low pH. The qualitative outcome of these two alternatives is identical.

Journal Article↗

PubMed2004

Relationship of abomasal histology and parasite-specific immunoglobulin A with the resistance to Haemonchus contortus infection in three breeds of sheep.

This study was carried out to evaluate the relationship of abomasal inflammatory cells and parasite-specific immunoglobulin A (IgA) in mucus, with the resistance to Haemonchus contortus infection in three breeds of sheep naturally infected with gastrointestinal nematodes. The breeds were the native Santa Ines sheep, and the European Suffolk and Ile de France breeds. Mast cells, eosinophils and globule leucocytes were enumerated in abomasal mucosa. Eosinophils within the sub-mucosa also were counted separately. Histamine concentration was estimated in abomasal tissue samples. Enzyme-linked immunosorbent assay was carried out in mucus samples to determine the level of IgA anti-H. contortus third and fifth instar. There were no significant differences among group means of these variables (P>0.05). The correlation coefficients between fecal egg counts (FEC)xmast cells (r=-0.490; P<0.05) and FECxeosinophils in sub-mucosa (r=-0.714; P<0.01) was significant in the Santa Ines sheep. In the Ile de France group, the correlation coefficients between globule leucocytesxFEC (r=-0.879; P<0.001) and histaminexworm burden (r=-0.833; P<0.01) were also significant. In the Santa Ines and Ile de France sheep, correlation coefficients between IgA anti-L3xworm burden and IgA anti-L3xFEC were negative. In general, inflammatory cells and IgA-parasite-specific in abomasum were inversely associated with H. contortus worm burden and FEC indicating that they may impair parasite development or fecundity in the three breeds of sheep. However, similar mean values of inflammatory cells and IgA were found in the resistant (Santa Ines) and in the susceptible (Suffolk and Ile de France) breeds of sheep. The enumeration of cells by histological assessment does not provide information on their functional activity, which may be different among breeds. Thus, the effect of breed on the functional activity of these and other inflammatory cells is an important area for further study.

Abomasum↗

PubMed2000

Genetic differences in the frequency of the hinge variants of porcine IgA is breed dependent.

The distribution of the IgA(a) and IgA(b) alleles of porcine IgA in over 160 randomly-selected animals revealed an abundance of heterozygotes but only two b/b homozygotes. Since the IgA(b) allotype is a splice site mutant lacking two-thirds of the hinge, this study tests the hypothesis that pigs with this genotype may be at a selective disadvantage while heterozygous individuals may be at some advantage. This hypothesis was tested by collecting data on 374 animals of known breed and often parentage. We show here that when breed was not considered, young animals of known parentage had genotypic frequencies identical to that expected for Mendelian alleles but that a/b heterozygotes were overrepresented in adults. However, when analyzed with regard to breed, a very strong association between breed and the frequency of the IgA(a) and IgA(b) alleles was discovered. Meishan and NIH minipigs were homozygous for IgA while heterozygotes predominated in Berkshire, Chester White, Durocs, Hampshire and Landrace. Animals homozygous for IgA(b) were best represented in the White Cross line. We show here that this very strong breed dependency of IgA allotypy in swine can produce a sample bias that can explain why only two b/b homozygotes (1.3%) were found in the 160 randomly-selected samples since the original samples came from primarily Landrace and Yorkshire animals. The expected frequency of b/b homozygotes in these breeds would be <3%. Thus, the data presented here reject the hypothesis that swine homozygous for a trait that results in loss of two-thirds of the IgA hinge, are selected against and that heterozygotes are positively selected. Rather, the study shows that IgA(a) and IgA(b) appear to be simple, breed-dependent allotypic markers.

Alleles↗

PubMed2001

Ownership pattern and management practices of small ruminants in The Gambia - implications for a breeding programme.

In the framework of a genetic improvement scheme a countrywide survey of small ruminant owners was conducted in The Gambia to obtain information about the ownership pattern, reasons for keeping and especially about breeding and management practices including housing and feeding. The main results were the following: women play a major role in small ruminant production, representing 52% of the owners of sheep, 67% of the owners of goats and 43% of the owners of both sheep and goats. The average number of animals owned is quite low (about six head of sheep and goats each, out of which about three are breeding females). Most of the breeding males are born in their respective flock and there are fewer breeding bucks than breeding rams. However, there are sufficient numbers of breeding males around. Animals are mainly left free to roam around during the dry season, and are either tethered or herded in the rainy season. During night animals are housed or tied under a shelter. Supplementary feeding is not common and vaccination against Pest des Petit Ruminants (PPR) and Pasteurellosis is only partly carried out. Implications for the establishment and structure of a multiplication tier within a three tier breeding scheme, nucleus-->multipliers-->farmers are discussed.

Journal Article↗

PubMed2005

High variability of milk protein genes in Bos indicus cattle breeds of Cameroon and Nigeria and characterization of a new alphas1-casein promoter allele.

The study provides the first comprehensive information on the variability of milk protein genes of Bos indicus and Bos taurus cattle breeds in Cameroon and Nigeria. The investigations indicate a high diversity of milk protein genes for the zebu populations. Of the investigated alleles, 21 out of 29 were observed. The method of single strand conformation polymorphism (SSCP) was a particularly useful technique because it allowed discrimination of alleles, including zebu-specific alleles at the CSN2 (I) and CSN3 (A(I) and H) loci, not separated by protein electrophoretic techniques and also made possible the detection of a further CSN1S1 5' promoter allele (CSNIS1Prom5), which is also zebu-specific. Characterization of CSN1S1Prom5 showed that it was the most variable of all described CSN1S1 promoter alleles. A potential GATA consensus motif is created by mutations in CSN1S1Prom5. Intra-breed diversity measured as mean effective number of alleles was higher in the zebu populations than in the taurine breeds. Of the expected casein haplotypes, 96 out of 320 were present in the studied breeds. 2-C-A-A2-H (CSN1SIProm2-CSN1S1C-CSN1S2A-CSN2A2-CSN3H) and 5-C-A-A2-H were zebu-specific while 1-B-A-A2-B was specific to the taurines. Overall distribution of alleles and haplotypes clearly separated the zebu populations from the taurine breeds. Zebu influence on the taurine breed Namchi was detected through the occurrence of zebu alleles and haplotypes. High variability of milk proteins also means availability of resources for breed development, phylogenetic studies, and conservation and management decisions.

Animals↗

PubMed2000

Structure and genetic relationship among Brazilian naturalized and imported goat breeds.

Fourteen goat populations were studied regarding their genetic relationship and structure. Parameters of genetic diversity (HT, HS and GST) and F statistic (FIS, FIT and FST) were estimated. Undefined breed populations presented high homogeneity, as did imported breed populations. Naturalized breed populations showed high differentiation. The genetic distances separating these 14 goat populations were calculated from gene frequency data for eight blood genetic markers (esterase D, phosphoglucomutase 1, carbonic anhydrase II, peptidase B, amylase, haemoglobin, transferrin, and protein X). Working with the genetic distance matrix of Nei corrected for small samples (DA), we constructed a dendrogram using the unweighted pair group method with arithmetic mean. DA values ranged from 0.0027 to 0.1518. The dendrogram divided the populations into two groups, one consisting of three populations of naturalized breeds, and another including the other populations (imported breeds, undefined breeds and some other naturalized breeds).

Animals↗