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PubMed2006

The effects of selective breeding against scrapie susceptibility on the genetic variability of the Latxa Black-Faced sheep breed.

Breeding sheep populations for scrapie resistance could result in a loss of genetic variability. In this study, the effect on genetic variability of selection for increasing the ARR allele frequency was estimated in the Latxa breed. Two sources of information were used, pedigree and genetic polymorphisms (fifteen microsatellites). The results based on the genealogical information were conditioned by a low pedigree completeness level that revealed the interest of also using the information provided by the molecular markers. The overall results suggest that no great negative effect on genetic variability can be expected in the short time in the population analysed by selection of only ARR/ARR males. The estimated average relationship of ARR/ARR males with reproductive females was similar to that of all available males whatever its genotype: 0.010 vs. 0.012 for a genealogical relationship and 0.257 vs. 0.296 for molecular coancestry, respectively. However, selection of only ARR/ARR males implied important losses in founder animals (87 percent) and low frequency alleles (30 percent) in the ram population. The evaluation of mild selection strategies against scrapie susceptibility based on the use of some ARR heterozygous males was difficult because the genetic relationships estimated among animals differed when pedigree or molecular information was used, and the use of more molecular markers should be evaluated.

Alleles↗
PubMed1993

Contribution of breed, cow weight, and milk yield to the preweaning, feedlot, and carcass traits of calves in three beef breeding systems.

Data were obtained from 1980 to 1987 on animals belonging to one of three breeding systems: Hereford, small rotation, and large rotation. Differences among Angus-, Gelbvieh-, Pinzgauer-, and Tarentaise-sired calves within the small rotation system were generally not detected as significant for the preweaning traits of gestation length, calving ease, birth weight, gain to weaning, or creep feed intake with the exception of a longer gestation length for Gelbvieh-sired calves. Similarly, differences for feedlot gain, days on feed, feedlot intake, and the carcass characteristics of carcass weight and marbling, and lean, fat, and bone percentages were generally nonsignificant. Gelbvieh- and Pinzgauer-sired calves had higher growth rate, market weight, and longissimus muscle area than Angus- or Tarentaise-sired calves with a corresponding tendency for increased feed intake. Differences among Charolais-, Maine Anjou-, and Simmental-sired calves within the large rotation were not significant for any of the traits studied. Increased cow weight was positively associated with birth weight, significantly so for the small rotation. No patterns of association with cow weight were found for other preweaning traits. Increased milk yield was positively, but not always significantly, associated with gestation length and all weights and was negatively associated with creep intake. Neither cow weight nor milk yield showed any consistent association with feedlot or market traits, although increased milk yield was shown to be associated with higher daily gains for Hereford and small rotation and with higher carcass and market weights for Hereford. In general, associations of traits of calves with weight and milk yield of their dams were not detected as being different among breeding systems; except the effect of increased milk yield on gain to weaning was greater in Hereford than in large rotation cows.

Adipose Tissue↗
PubMed1998

Influence of production circumstances and economic evaluation criteria on economic comparison of breeds and breed crosses.

The ranking of genotypes (i.e., breeds and breed crosses) for economic performance depends on the production circumstances of the herd and the criteria for economic evaluation. In this study, the effects of evaluation criteria and production circumstance are quantified using data from the literature on six genotypes. The economic evaluation criteria measured at herd level included lifetime profit and lifetime profit expressed per day of calving interval, per day of productive lifetime, per day of total herd life, per unit of milk, and per unit of feed energy. Four production circumstances were studied; these circumstances included constraints on the output of milk and on herd use of concentrates, roughages, and both concentrates and roughages. Profit was determined based on the sale of milk, calves, cull cows, and heifers and the expenses incurred for concentrates and roughages, animal deaths, milking time, interest, and other inputs. Results indicate that production circumstances and evaluation criteria largely influence the ranking of genotypes and, therefore, the outcome of economic comparisons. The genotype that ranks the best under a certain criteria and circumstance ranks differently when these situations are altered. In economic comparisons of genotypes aimed at offering recommendations for implementation in smallholder dairy production systems in the tropics, the choice of the evaluation criteria should be determined by the limitation or constraint that characterizes the area where the genotypes are to produce or are currently producing. For example, for situations in which feed availability is limiting, genotypes should be ranked on total profit per unit of feed energy.

Animal Feed↗
PubMed2001

Out-of-season breeding of milk goats--the effect of light treatment, melatonin and breed.

The purpose of this study was to evaluate the effectivity of melatonin in addition to light treatment (exposure to 2 hours of light during the night = a long-day photoperiod) to modify the breeding season of Saanen and cross-bred milk goats and to compare the difference between the breeds. Twenty-two Saanen and 22 cross-bred does were randomly divided into 3 treatment groups. Group 1 (controls) received no treatment, Group 2 received light treatment for 37 days and Group 3 received light treatment plus melatonin implants after the light treatment. After a further 35 days the 3 groups were brought together and a billy goat that had also been exposed to the extra light at night, had received a melatonin implant and had been isolated from the does during the treatment period, was introduced to the does for natural mating. Ultrasound scanning was used to diagnose pregnancy and all the pregnant goats kidded. Significantly more Saanen does compared to cross-bred does (P = 0.018) became pregnant and kidded after natural mating, when the group that received melatonin as well as light treatment was compared to the group that received light treatment only. Compared to light treatment only, the addition of melatonin to light treatment improved (P = 0.0028) conception after natural mating, in both the Saanen and the cross-bred does.

Animals↗
PubMed1976

Progress report on the Charles River Breeding Laboratories' free-ranging rhesus monkey breeding colony on Key Lois, Florida.

The nucleus of a breeding colony of free-ranging rhesus monkeys (Macaca mulatta) free from tuberculosis, herpes-B virus, shigellosis, and salmonellosis has been established on Key Lois, Florida, USA. Standardized procedures for trapping, quarantine, and shipping from the wild in India to the island have been established. The monkeys seem to have adapted well to the Florida Keys' climate. Reproduction has proceeded according to expectations, and social groups have been formed with continual restructuring as each new group is placed on the island. The isolation of Key Lois from other inhabited keys by the open sea affords good isolation and has discouraged intrusion by unwanted visitors. The operational costs of this island breeding program are encouraging. It is projected that by 1976 or 1977, monkeys should be available from this colony at a lower price than for animals bred in indoor facilities; and their availability will be in excess of animals trapped in the forest and subjected to a conventional conditioning and quarantine period.

Animal Feed↗
PubMed1989

[Variations in the concentrations of the immunoglobulins IgG1, IgG2, IgM and IgA in sheep. 1. Changes in the blood serum and in the milk of sheep of different breeds and cross-breeds during lactation].

A total of 103 ewes from the breeds Black mutt., Texel, Finn. L., Heidschnucke and the crossbreeds Texel x Finn. L. and Black. mutt. x Finn. L. was studied. Blood samples were drawn at days 1, 7, 21 and 42 and milk samples at the 4th, 12th, 24th and 72nd hour after the onset of lactation and subsequently on days 7, 21 and 42. The concentrations of the immunoglobulins IgG1, IgG2, IgM and IgA were assayed in serum and milk. The following results were obtained: 1. The total immunoglobulin contents in the serum was not significantly different between breeds. 2. All ewes showed a rise in serum immunoglobulin concentrations by about one third over the first six weeks of lactation. Between 50-60% of this increase were on the account of IgG1. 3. The serum concentration of IgG1 and IgG1 rose as of the third day, those of IgM as of day 21 after lambing. 4. The rise in serum immunoglobulin concentration continued after the weaning of the lambs. 5. The ratio of IgG1 to IgG1 in ewe serum was 2:1. 6. The immunoglobulin concentration in milk dropped sharply on the first day of lactation, followed by a continuous, more gradual decrease over the entire course of lactation. A terminal rise, as observed in sows, could not be detected. 7. The ratio of IgG1:IgG2 : IgM : IgA in the whey changed from 85 : 1 : 12 : 2 on day one to 70 : 7 : 12 : 11 on the last day of lactation. 8. While characteristic trends in immunoglobulin patterns in the sera of ewes over the course of lactation are clearly discernible, it is not possible to denote "normal" values.

Animals↗
PubMed2001

Growth curve analyses are best suited to examine the relation between developmental pathways and selective breeding: comment on Hofer, Shair, Masmela, & Brunelli, "Developmental effects of selective breeding for an infantile trait: the rat pup ultrasonic isolation call".

Hofer, Brunelli, Shair, & Masmela (2001) provide valuable information about the effects of selective breeding on rat-pup behaviors and physiology. Although the design and statistical analytic techniques employed are typical of those used to evaluate behavioral development in animals, I offer several suggestions about how to evaluate the influence of selective breeding on developmental pathways using modern statistical techniques. As Hofer et al. demonstrate, the development of rat behavior and physiology can be an excellent model for examining the relation between selection and development.

Age Factors↗
PubMed1992

Hormonal responses to removal of a breeding male in the cooperatively breeding white-browed sparrow weaver, Plocepasser mahali.

The white-browed sparrow weaver (Plocepasser mahali) is a cooperatively breeding Ploceid finch that lives in groups of up to 11 individuals. Each group consists of a dominant breeding male and female and a varying number of nonreproductive birds that help feed young and defend the group territory. Experimental removal of the dominant male resulted in attempts by other males to take over the group. Removal of a subordinate, nonbreeding male, as a control, resulted in no change of status among group members. During takeover, there was a transitory increase in plasma levels of luteinizing hormone in the new dominant male, but no change in testosterone levels. As reported in previous investigations, dominant males tended to have higher levels of testosterone than females or subordinate males, but this was not related to the heightened aggression of the takeover. Plasma levels of luteinizing hormone, testosterone, and corticosterone did not differ between the other status groups. The possibility that luteinizing hormone, or a hitherto unidentified androgen, may regulate aggression in the white-browed sparrow weaver is discussed.

Aggression↗
PubMed1991

Comparative gene frequencies between the Canchim breed of Brazil beef cattle and their foundation breeds.

1. Four hundred and seventy-five animals of the Canchim breed from EMBRAPA-UEPAE de Sao Carlos were analyzed by starch gel electrophoresis. 2. Albumin, amylase, transferrins, carbonic anhydrase, hemoglobin and nucleoside phosphorylase gene frequencies were compared with the same frequencies in the foundation breeds, Charolais and Indubrazil. 3. Theoretical values obtained considering the 5/8 European, 3/8 Zebu admixture are near the means calculated from our results and data from literature.

Amylases↗
PubMed2000

Analysis of diversity and genetic relationships between four Chinese indigenous pig breeds and one Australian commercial pig breed.

The genetic diversities and relationships of four Chinese indigenous pig breeds and one Australian commercial pig breed have been evaluated using 27 microsatellites recommended by the International Society of Animal Genetics (ISAG) and the Food and Agriculture Organization (FAO). The allele frequencies, effective numbers of alleles and the polymorphic information content have been calculated. Nei's standard genetic distances have been used to construct a UPGMA dendrogram, which has been evaluated by the Bootstrap test. The utility of microsatellites for evaluating genetic diversity of pigs is discussed.

Alleles↗
PubMed1986

Preweaning breed-of-sire comparisons involving the Senepol breed of cattle.

Preweaning data collected at two locations (Kentucky, Louisiana) were utilized to evaluate breed-of-sire comparisons involving the Senepol breed of cattle. For the Kentucky study, calves sired by Senepol bulls were 1.3 kg heavier (P less than .05) at birth than calves sired by Hereford bulls; however, weaning weights were similar for the two sire groups. For the Louisiana study, calves sired by Longhorn bulls were 5.3 kg lighter (P less than .01) at birth, 20 kg lighter (P less than .01) at weaning and had weaning condition scores .5 unit less (P less than .01) than the average of calves sired by Red Poll and Senepol bulls. Also, heifers exposed to Longhorn bulls weaned 23 kg less (P less than .01) calf per heifer exposed than the average of heifers exposed to Red Poll and Senepol bulls. Calves sired by Red Poll bulls were 1.2 kg heavier (P less than .01) at birth and 12 kg heavier (P less than .01) at weaning than those sired by Senepol bulls; however, the Senepol-sired calves received higher (P less than .01) condition scores at weaning. Heifers exposed to Red Poll bulls weaned 20 kg more (P less than .05) calf per heifer exposed than did heifers exposed to Senepol bulls.

Animals↗
PubMed1988

Effects of ram preexposure and ram breed on fertility of ewes in summer breeding.

Suffolk x Rambouillet ewes were used in two consecutive years to test the ability of Dorset and Suffolk yearling rams to stimulate ovulation and estrus in early summer (late June and July) breeding. After spring weaning about June 1, ewes were randomly divided into three groups and for 2 wk either were isolated from rams or were preexposed to either yearling Dorset or Suffolk rams by penning of rams in proximity to ewes. Ewes then were rerandomized into two groups for joining with either yearling Dorset or Suffolk rams fitted with marking harnesses. Serum progesterone profiles and crayon marks were used as indicators of ovulation and estrus. Overall lambing rate was not different among preexposure treatments for the 2 yr. However, early lambing rate (in the first 14 d of lambing season) was significantly affected by preexposure group (24% for Dorset vs 9% for Suffolk and 10% for isolation), especially in the 2nd yr (31% for Dorset vs 8% for both Suffolk and isolation). Ewes preexposed to Dorsets also lambed 10 d earlier (P less than .05) than ewes preexposed to Suffolks in yr 2, but the groups did not differ in yr 1. Ewes exposed to Dorset rams for breeding had higher overall lambing rates than ewes bred to Suffolks (75% vs 54%), especially in the 1st yr (77% vs 48%). Lambs sired by Dorset rams were born 6 d earlier in yr 1 (P less than .05) but only 1 d earlier in yr 2. Data from both years indicate that Dorsets are superior to Suffolks in ability to sire lambs in fall lambing systems.

Animals↗
PubMedDate not supplied

Testicular capillary blood flow in the impubertal lamb and the ram during the breeding and non-breeding seasons.

The testicular capillary blood flow was measured by the 133Xenon clearance technique in the Ile-de-France lambs and rams in Spring and Autumn. Anaesthetized animals were maintained in the supine position and 133Xe was injected into the testicle through the scrotal skin. In the adult, the blood-flow (ml/min./100 g) depended upon the season: 8.3 +/- 1.0 vs 12.7 +/- 0.7 in May and October (P less than 0.001). In the impubertal lamb (50 days old) regardless of the period of the year, the blood flow was the same as in the adult in the breeding season (11.4 +/- 1.2 vs 12.7 +/- 0.7). In prepubertal lambs (120 days old) the rapid increase in testicular weight was not correlated with an increase in the blood flow (9.4 +/- 0.7).

Animals↗
PubMedDate not supplied

Cause of death in dogs according to breed: a necropsy survey of five breeds.

The final necropsy diagnoses, obtained between 1985 and 1999, were compared among 1,206 golden retrievers, boxers, German shepherd dogs, Labrador retrievers, and rottweilers. A significantly larger proportion of boxers and golden retrievers died of neoplastic disease than the other three breeds. The ages at death were not significantly different among golden retrievers, German shepherd dogs, and Labrador retrievers. However, rottweilers and boxers died at a younger age from both neoplastic and nonneoplastic diseases. Although boxers were already known to be at a higher risk for neoplasia, a similar index of suspicion for neoplasia should now be used for golden retrievers.

Animals↗
PubMed1992

[The problem of breeding for spots in rabbits. 2. Further results on the variation of characteristics in fattening and breeding animals].

The mode of inheritance of spotting in both breeds (ES and DRS) is compatible with incompletely dominant resp. intermediate segregation, though a broad variability of spotted areas exists, indicating the influence of minor genes or other ontogenetic factors. Additional findings support the conclusion, that there is a very distinct predisposition of homozygous KK animals to develop megacolon with growing age. This also has consequences for the relative organ weight of the heart and of the adrenals in this genotype. Sporadically encountered accessory adrenal cortical tissue however did not exhibit genotypic preferences.

Adrenal Glands↗
PubMed1989

[Study of the possibility of breeding serologically negative animals from a breeding farm infected with serotype 2 Actinobacillus pleuropneumoniae].

Two sanitation trials showed that it was possible to rear serologically negative animals from pigs on a breeding farm infected with Actinobacillus pleuropneumoniae serotype 2. This was achieved by the medication of sows and piglets during the farrowing-house period and by isolating the piglets from the infected stock of pigs immediately after weaning. Medication of the sows consisted in administering sulphamethoxazole-trimethoprim in the drinking water for a period from five days before to eight days after farrowing. The piglets were treated by injections of sulphadoxine-trimethoprim on days 3, 10, 17 and 24.

Actinobacillus Infections↗
PubMed1994

[Breeding, advice and ecopathology. A didactic approach to situations involving breeding diagnosis in swine production].

Innovation, quality, variety and flexibility of production require simultaneously an improvement of professional skills and an increase in cooperation. However, this cooperation should not be reduced to a mere data exchange, but must extend to a co-construction of new representations and new action schemes. In this way, health advising integrates production and knowledge apprenticeship, which we studied using a didactic approach (from the knowledge point of view). In this article, we will establish that animal ecopathology, by the standardization of the breeding description through diagnostic activity, has contributed to the strengthening of the cooperation between the breeder and the practicien.

Animal Husbandry↗
PubMed1976

[Changes in the blood picture during puerperium of Czech white-breed sows under large-scale breeding conditions].

A dynamics of the changes of the red and while blood cell count during puerperium (1st-27th day post partum) was studied in 293 sows of the Czech White breed kept in typical large-scale production conditions. An average count of erythrocytes amounted to 5 513 000 +/- 385 514. In the course of puerperium their count slightly decreased in comparison with the value obtained on the first day p. p. (on the 10th day p. p. the decrease was even highly statistically significant - P less than 0.01). An average amount of hemoglobin was 12.48 +/- 1.22 g per 100 ml of blood; in the course of the nearly whole of puerperium it was slightly higher than on the first day p. p. (in the third week on the threshold of the statistical significance up to the statistical significance - P less than 0.10-0.05-0.01). The value of hematocrit did not fluctuate (average = 38.65 +/- 3.89%), sedimentation slowed down, especially from the end of the second week p. p. The protein of the blood plasma amounted, on an average, to 7.71 +/- 0.84 g per 100 ml; the protein content raised during puerperium in comparison to the 1st day .p. An average count of leukocytes during puerperium was in comparison to the 1st day p.p. An average count of leukocytes during puerperium 12 755 +/- 1529, and it slightly increased in relation to the 1st day p. p. The percentage of neutrophile granulocytes and lymphocytes did not change very much; it reached 46%: 45%. The character of the sow blood during puerperium fluctuated all the time between neutrophile and lymphocytic type with a slight tendency to the prevalence of neutrophile granulocytes. Nevertheless, the proportion of neutrophile granulocytes with rodlike nuclei decreased, and on the other hand, the proportion of neutrophile granulocytes with segmented nuclei increased (a nucleus shift to the right). Original values and ratio of the first day p. p. (T = 6.91%: Seg = 41.13%) changed in the average value of T = 1.93%: Seg = 43.96% during the whole puerperium.

Animal Husbandry↗