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PubMed1990

Seasonal cycles in the blood plasma concentration of FSH, inhibin and testosterone, and testicular size in rams of wild, feral and domesticated breeds of sheep.

Seasonal cycles in testicular activity in rams were monitored in groups of wild (mouflon), feral (Soay) and domesticated breeds of sheep (Shetland, Blackface, Herdwick, Norfolk, Wiltshire, Portland and Merino) living outdoors near Edinburgh (56 degrees N). The changes in the blood plasma concentrations of FSH, inhibin and testosterone, and the diameter of the testis were measured every half calendar month from 1 to 3 years of age. There were significant differences between breeds in the magnitude and timing of the seasonal reproductive cycle. In the mouflon rams, the seasonal changes were very pronounced with a 6-15-fold increase in the plasma concentrations of FSH, inhibin and testosterone from summer to autumn, and a late peak in testicular diameter in October. In the Soay rams and most of the domesticated breeds, the seasonal increase in the reproductive hormones occurred 1-2 months earlier with the peak in testicular size in September or October. In the two southern breeds (Portland and Merino), the early onset of testicular activity was more extreme with the seasonal maximum in August. In cross-bred rams, produced by mating Soay ewes (highly seasonal breed) with Portland or Merino rams (less seasonal breeds), there was a seasonal reproductive cycle that was intermediate compared to that of the parents. A comparison between all 11 breeds showed a significant correlation between the timing of the seasonal cycle in plasma FSH concentration and testicular diameter (time of peak FSH vs testis, r = 0.95). The overall results in the rams are consistent with a primary role of FSH in dictating the seasonal cycle in testicular size and the secretion of inhibin. The earlier seasonal onset in the testicular cycle in the southern breeds of domesticated sheep, and the differences from the wild type, are taken to represent the effects of genetic selection for a longer mating season.

Animals↗
PubMedDate not supplied

Breed risk of pyometra in insured dogs in Sweden.

An animal insurance database containing data on over 200,000 dogs was used to study the occurrence of pyometra with respect to breed and age during 1995 and 1996 in Swedish bitches <10 years of age. A total of 1,803 females in 1995 and 1,754 females in 1996 had claims submitted because of pyometra. Thirty breeds with at least 800 bitches insured each year were studied using univariate and multivariate methods. The crude 12-month risk of pyometra for females <10 years of age was 2.0% (95% confidence interval = 1.9-2.1%) in 1995 and 1.9% (1.8-2.0%) in 1996. The occurrence of pyometra differed with age, breed, and geographic location. The risk of developing pyometra was increased (identified using multivariate models) in rough Collies, Rottweilers, Cavalier King Charles Spaniels, Golden Retrievers, Bernese Mountain Dogs, and English Cocker Spaniels compared with baseline (all other breeds, including mixed breed dogs). Breeds with a low risk of developing the disease were Drevers, German Shepherd Dogs, Miniature Dachshunds, Dachshunds (normal size), and Swedish Hounds. Survival rates indicate that on average 23-24% of the bitches in the databases will have experienced pyometra by 10 years of age. In the studied breeds, this proportion ranged between 10 and 54%. Pyometra is a clinically relevant problem in intact bitches, and differences related to breed and age should be taken into account in studies of this disease.

Age Factors↗
PubMed2000

Breeds of dogs involved in fatal human attacks in the United States between 1979 and 1998.

OBJECTIVE: To summarize breeds of dogs involved in fatal human attacks during a 20-year period and to assess policy implications. ANIMALS: Dogs for which breed was reported involved in attacks on humans between 1979 and 1998 that resulted in human dog bite-related fatalities (DBRF). PROCEDURE: Data for human DBRF identified previously for the period of 1979 through 1996 were combined with human DBRF newly identified for 1997 and 1998. Human DBRF were identified by searching news accounts and by use of The Humane Society of the United States' registry databank. RESULTS: During 1997 and 1998, at least 27 people died of dog bite attacks (18 in 1997 and 9 in 1998). At least 25 breeds of dogs have been involved in 238 human DBRF during the past 20 years. Pit bull-type dogs and Rottweilers were involved in more than half of these deaths. Of 227 reports with relevant data, 55 (24%) human deaths involved unrestrained dogs off their owners' property, 133 (58%) involved unrestrained dogs on their owners' property, 38 (17%) involved restrained dogs on their owners' property, and 1 (< 1%) involved a restrained dog off its owner's property. CONCLUSIONS: Although fatal attacks on humans appear to be a breed-specific problem (pit bull-type dogs and Rottweilers), other breeds may bite and cause fatalities at higher rates. Because of difficulties inherent in determining a dog's breed with certainty, enforcement of breed-specific ordinances raises constitutional and practical issues. Fatal attacks represent a small proportion of dog bite injuries to humans and, therefore, should not be the primary factor driving public policy concerning dangerous dogs. Many practical alternatives to breed-specific ordinances exist and hold promise for prevention of dog bites.

Animals↗
PubMed2004

Comparison of two radiographic techniques for evaluation of hip joint laxity in 10 breeds of dogs.

OBJECTIVE: To evaluate hip joint laxity in 10 breeds of dogs via 2 radiographic techniques. ANIMALS: 500 clinically normal dogs. DESIGN: Prospective study. PROCEDURE: Radiographs obtained via routine hip joint evaluations performed in sedated dogs of 10 popular breeds were randomly selected from a database. Measurements of distraction index (DI) and hip-extended index (HEI) on 1 hip joint radiograph randomly chosen from each dog were made. RESULTS: Mean age of dogs was 20.7 months. Mean HEI was 0.17 (range, 0.0 to 0.72) and mean DI was 0.44 (range, 0.07 to 0.96). Borzois had uniformly tight hip joints as judged by use of both methods and were considered the gold standard by which hip joint laxity was judged (all Borzois had DI < or = 0.32). Overall, DI was significantly greater than HEI. Within each breed, mean DI was always greater than mean HEI. Significant differences were detected among breeds for HEI; however, compared with DI, the magnitude of differences among breeds was less. CONCLUSIONS AND CLINICAL RELEVANCE: Distraction radiography detected the greatest range and magnitude of passive hip laxity in the 10 breeds of dogs. The difference in values between breeds known to have high prevalence of canine hip dysplasia and those in Borzois was greater for DI than for HEI. Breeds must be evaluated individually because of inherent differences in hip joint laxity.

Animals↗
PubMed1993

Reproductive and maternal performance of rotational three-breed, and inter se crossbred cows in Florida.

Reproductive, calf growth, and cow weight data were collected during a 16-yr period in southern Florida. Data included 1,767 calves at weaning from purebred, F1, backcross, F2, and three-breed crossbred cows of the Angus (A), Brahman (B), and Charolais (C) breeds. The purebred cows primarily produced purebred calves, the F1 and F2 Cows produced inter se crossbred calves, and the backcross cows produced 3/8:5/8 calves. The 1/2 C:1/4 A:1/4 B three-breed crossbred cows were mated to A series, whereas three-breed crossbred dams with breed compositions of 1/2 B:1/4 A:1/4 C, and 1/2 A:1/4 B:1/4 C were mated to C and B sires, respectively. For analysis of additive breed and heterosis effects, pregnancy rate and cow weight were considered to be traits of the dam alone. The A additive breed effect increased (P < .05) pregnancy rate but reduced (P < .001) cow weight. The effects of AB, AC, and BC heterozygosity all increased pregnancy rate, but the advantage was greater for the crosses that involved B. Both AB and BC heterozygosity increased (P < .001) cow weight, whereas AC did not. The additive direct effect of B and C increased birth weight (BWT) and weaning weight (WWT). The additive maternal effect of B reduced BWT. The direct effect of AB heterozygosity increased BWT and WWT, and that of BC increased only WWT (P < .001). A comparable pattern was observed for maternal heterosis on weight traits. A much smaller effect of AC maternal heterosis on WWT was found. Pregnancy rates of F1, backcross, and three-breed dams were similar.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2006

Effects of breed, sex, and halothane genotype on fatty acid composition of pork longissimus muscle.

The objective of this study was to estimate the effects of breed, sex, and halothane genotype on fatty acid composition and several fatty acid indices of lipid extracted from porcine LM. Purebred Yorkshire (n = 436), Duroc (n = 353), Hampshire (n = 218), Spotted (n = 187), Chester White (n = 173), Poland China (n = 124), Berkshire (n = 256), and Landrace (n = 187) pigs (n = 1,934; 1,128 barrows and 806 gilts) from 1991, 1992, 1994, and 2001 National Barrow Show Sire Progeny Tests were used. Pigs were classified as the HAL-1843 normal (NN) genotype (n = 1,718) or the HAL-1843 carrier (Nn) genotype (n = 216). For statistical analysis, a mixed model was used that included fixed effects of breed, sex, halothane genotype, test, slaughter date, interaction of breed x sex, and random effects of sire and dam within breed. Breed significantly affected the concentration of individual fatty acids, total lipid content, and the values of several fatty acid indices of LM. Duroc pigs had the greatest (P < 0.01) content of total SFA. Total MUFA concentration in Poland China pigs was greater (P < 0.05) than in all other breeds except the Spotted (P > 0.05). The concentrations of total PUFA were greater (P < 0.01) in Hampshire, Landrace, and Yorkshire pigs compared with those of other breeds. Significant sex differences for individual fatty acids were detected. Compared with gilts, barrows had greater (P < 0.01) concentrations of SFA and MUFA but lower (P < 0.01) total PUFA. Halothane genotype was a significant source of variation for the percentages of some fatty acids. Pigs with the carrier (Nn) genotype had lower concentrations of SFA (P < 0.05) and MUFA (P < 0.01) but a greater concentration of PUFA (P < 0.01) compared with NN pigs. There were significant negative correlations between total lipid content and individual PUFA and significant positive correlations between lipid concentration and most individual SFA and MUFA. In conclusion, the results suggest that breed and sex are important sources of variation for fatty acid composition of LM.

Anesthetics, Inhalation↗
PubMed1982

Puberty in beef bulls: acrosome morphology and semen quality in bulls of different breeds.

Semen characteristics were evaluated every 2 wk from 7 through 13 mo of age in 31 beef bulls representing six breed groups (Hereford, Angus, Hereford x Angus crossbreeds, Angus x Hereford crossbreds, Red Poll and Brown Swiss). Breeds differed in age at puberty, defined as the age at which an ejaculate was first obtained that contained a minimum of 50 x 10(6) total spermatozoa with at least 10% progressive motility (Hereford, 326 +/- 9 d; Angus, 295 +/- 4 d; Hereford x Angus, 300 +/- 8 d; Angus x Hereford, 296 +/- 9 d; Red Poll, 283 +/- 9 d and Brown Swiss, 264 +/- 9 d). Significant breed differences also were observed in concentration of spermatozoa, progressive motility, seminal protein concentration, abnormal spermatozoa and acrosomal morphology. Considerable variation was observed for the majority of pubertal traits among the 31 bulls, indicating that differences in stage of pubertal development existed among and within breeds of beef bulls between 7 and 13 mo of age. However, adjustment of data to age at puberty negated breed differences (P greater than .10), indicating that the pubertal patterns of change occurring in each semen characteristic were similar for the breeds evaluated. Concentration of spermatozoa, progressive motility, seminal protein concentration, percentage spermatozoa with normal head and tail morphology and percentage spermatozoa with normal acrosomal morphology increased (P less than .01) from puberty through 16 wk after puberty in all bulls and all breds. During the first 6 wk after puberty, rapid increases (P less than .01) were observed in percentage spermatozoa exhibiting normal head morphology (excluding acrosomes) and progressive motility, and a rapid decrease (P less than .01) was observed in percentage spermatozoa with proximal cytoplasmic droplets, with values at +6 wk approaching those reported for mature bulls. Percentage spermatozoa with normal acrosomal morphology and concentration of spermatozoa improved more slowly and had not reached mature levels by 16 wk after puberty. Because age at puberty varied by 62 d among breeds and 88 d among bulls and important characteristics of semen quality improved slowly after puberty, careful evaluation of the stage of pubertal development in individual bulls is recommended before selecting young bulls for natural breeding or artificial insemination. Additional investigations are needed to define the patterns of pubertal development through sexual maturity in beef bulls and to establish relationships to fertility.

Acrosome↗
PubMed1983

Nutrient requirements to maintain weight of mature, nonlactating, nonpregnant cows of four diverse breed types.

Four breed types with 12 cows/breed-type (Hereford x Angus, AHx; Charolais and Angus and Charolais x Hereford, Cx; Jersey x Angus, Jersey x Hereford, Jx and Simmental x Angus, Simmental x Hereford, Sx) were used to estimate nutrient requirements for zero daily weight change. Four nonpregnant, nonlactating cows of each breed type were assigned to one of three feeding levels [90 kcal metabolizable energy (ME).kg body wt (kg)-.75 . d-1, 150 kcal ME.kg-.75.d-1 and ad libitum] for a 140 d feeding period. The feeding trial was: Period 1 (d 0 to 70) and Period 2 (d 70 to 140). Effect of breed type, feeding level and the two-way interaction upon weight, weight change and feed intake data were initially analyzed. Two-factor interactions tended not to be significant for weight and weight change. The main effects of breed type and feeding level tended to be significant for weight and weight change in each of the periods. On d 0, the Sx (570 +/- 13 kg) and Cx (578 +/- 14 kg) were heavier (P less than .05) than the AHx (527 +/- 13 kg) all of which were heavier than the Jx (458 +/- 14 kg). Under the two restricted diets, the breed type ranking for dry matter intake corresponded to the ranking for initial body weight. However, at the ad libitum feeding level, the Cx tended to consume less dry matter than the other breed types. Measures of weight change were evaluated to test the effect of breed type and dry matter intake. The effect of breed type was significant only for daily weight change (kg/d) during Period 2. The linear and(or) quadratic effects of dry matter intake (2.53 Mcal ME/kg dry matter) on measures of weight change were significant in all periods. During Period 1, the pooled dry matter intake estimate for zero daily weight change and zero metabolic weight change were 8.1 kg/d and 75.3 g.kg-.75.d-1, respectively. For AHx, Cx, Jx and Sx during Period 2, daily dry matter intake for zero weight gain was 4.2, 5.3, 4.2 and 5.5 kg/d, respectively. A pooled estimate of 43.9 g . kg-.75 . d-1 was obtained for dry matter intake relative to metabolic size in Period 2.

Animals↗
PubMed1985

Interval to first postweaning estrus and causes for leaving the breeding herd in Large White, Landrace, Yorkshire and Chester White females after three parities.

Three hundred and five Large White (LW, 93), Landrace (L, 92), Yorkshire (Y, 69) and Chester White (CW, 51) gilts produced at the Roman L. Hruska U.S. Meat Animal Research Center over 3 yr with 15 to 41 gilts per breed group per year were housed in total confinement and mated to farrow at 1 yr of age. After 28 to 30 d lactation, piglets were weaned and all females were observed for estrus daily for 30 d. During the year that each gilt initially farrowed, she was mated to produce a second and third litter if she returned to estrus within 30 d after piglet removal. Interval from weaning (d 0) to estrus and reason for leaving the breeding herd were recorded for each animal. Interval from weaning to estrus was influenced by breed (P less than .01), parity (P less than .01) and interaction between breed and parity (P less than .01). Intervals from weaning to estrus, in first parity females which exhibited estrus, were 7.8, 6.6, 9.3 and 14.0 d for the LW, L, Y and CW breeds. Intervals for all females after the second litter were 6.8, 4.9, 8.0 and 9.1 d, and after the third litter 6.4, 5.2, 8.3 and 10.1 d for the LW, L, Y and CW breeds. Breed, parity and year (P less than .01) affected the number of females not exhibiting estrus. Percentages of females not exhibiting estrus were 6.5, 18.7, 37.7 and 23.5 for the LW, L, Y and CW breeds and 16.1, 2.3 and 2.0 for sows after the first, second and third parities.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

Economic evaluation of alternative crossbreeding systems involving four breeds of swine. I. The simulation model.

A static, deterministic computer model, programmed in Microsoft Basic for IBM PC and Apple Macintosh computers, was developed to calculate production efficiency (cost per kg of product) for nine alternative types of crossbreeding system involving four breeds of swine. The model simulates efficiencies for four purebred and 60 alternative two-, three- and four-breed rotation, rotaterminal, backcross and static cross systems. Crossbreeding systems were defined as including all purebred, crossbred and commercial matings necessary to maintain a total of 10,000 farrowings. Driving variables for the model are mean conception rate at first service and for an 8-wk breeding season, litter size born, preweaning survival rate, postweaning average daily gain, feed-to-gain ratio and carcass backfat. Predictions are computed using breed direct genetic and maternal effects for the four breeds, plus individual, maternal and paternal specific heterosis values, input by the user. Inputs required to calculate the number of females farrowing in each sub-system include the proportion of males and females replaced each breeding cycle in purebred and crossbred populations, the proportion of male and female offspring in seedstock herds that become breeding animals, and the number of females per boar. Inputs required to calculate the efficiency of terminal production (cost-to-product ratio) for each sub-system include breeding herd feed intake, gilt development costs, feed costs and labor and overhead costs. Crossbreeding system efficiency is calculated as the weighted average of sub-system cost-to-product ratio values, weighting by the number of females farrowing in each sub-system.

Animal Husbandry↗
PubMed1987

Reproductive performance of Suffolk and Suffolk-cross ewes and ewe lambs exposed to vasectomized rams before breeding.

Multiparous Suffolk and Suffolk-cross ewes were randomly allotted to treatments within breed and year to measure effects of ram exposure, during transition from anestrus to breeding activity, on reproductive performance. Treatments were: 1) ewes joined with two mature vasectomized Rambouillet rams for 15 d before breeding (DC), 2) ewes maintained across a net wire fence from two vasectomized rams for 15 d before breeding (FC) and 3) ewes maintained approximately 400 m away from rams (NC). At the end of the 15 d, all ewes were placed in one pasture and mated to three fertile Suffolk rams during a 34-d breeding season. A total of 96 Suffolk and 177 Suffolk-cross ewes was utilized during the 3-yr experiment. A greater (P less than .05) prebreeding ovulation percentage was observed in DC and FC than in NC ewes. Mating and lambing occurred approximately 6 d earlier for DC or FC ewes than for NC ewes. A similarly designed experiment was conducted using Suffolk and Suffolk-cross ewe lambs allotted to treatments within breed and year to measure effects of ram exposure during the natural breeding season, but prior to breeding. Treatment differences were not detected (P greater than .05) for date of first observed estrus, date of lambing, percentage of ewes lambing in the first 17 d of the lambing season, number of lambs born per ewe lamb exposed or number of lambs born per ewe lamb giving birth.

Anestrus↗
PubMed2002

Is crossbreeding the answer to questions of dairy breed utilization?

The current interest in crossbreeding in the commercial dairy industry, even though it is quite limited, raises questions of breed utilization. Fewer than 5% of US dairy cattle are other than purebred or grade Holsteins. The large advantage of Holsteins for additive genetic merit for lactation milk yield is apparently responsible for this trend. Why, then, this interest in crossbreeding? The economic importance of traits such as reproduction, health, and survival in dairy production systems is likely the basis for the interest in crossbreeding, even though these traits are secondary to milk yield. Several US studies and a Canadian study confirmed that while several crossbred groups were equivalent to Holsteins for lactation milk yield, none were superior. Two crossbred groups in the Canadian study had lifetime yields, milk value, and net returns equivalent to Holsteins. In the New Zealand study, Friesian-Jersey reciprocal crossbreds were predicted to exceed Friesians in first-lactation fat yield. Crossbred performance is dictated by a combination of additive and nonadditive genetic effects. Evidence exists for direct. maternal, heterosis, and cytoplasmic maternal effects. Heterosis of 15 to 20% for lifetime traits was found in two studies. Results from previous crossbreeding studies have something to recommend for inclusion of Holstein, Ayrshire, Brown Swiss, and Jersey breeds in a crossbreeding scheme. However, multiple-generation lifetime performance on an array of purebreds and crossbreds under US condition does not exist. Full unique identification of individual animals, including breed composition, would permit the use of DHIA data to estimate additive and nonadditive genetic parameters for the traits recorded therein. Survival data from birth and health data would need to be fully recorded to provide complete data on lifetime performance. Self-propagation of crossbred replacements is mandatory if any crossbreeding system is to be successful. Based on current empirical data, a two-breed rotational crossing system appears to be the most viable system to maximize economic merit. The theoretical advantages of a three-breed rotational crossing system are clear, but the data to recommend the third breed and this system in practice are limited. Full-scale long-term breeding experiments or analysis of field data paired with a comprehensive modeling of alternative breed utilization strategies for US conditions are recommended.

Animals↗
PubMed1995

Comparative yolk cholesterol content in four Spanish breeds of hens, an F2 cross, and a White Leghorn population.

Yolk cholesterol content (milligrams per gram of yolk and milligrams per egg) was studied in eggs of four Spanish breeds of hens (Castellana, Buff Prat, Vasca, and Villafranquina), an F2 from a cross between Castellana and Buff Prat (C x BP-F2), and a White Leghorn population. Birds were tested at 30 wk of age. There were differences among breeds (P < .001), cholesterol concentration being significantly lower in the C x BP-F2 (13.14 +/- .26 mg/g yolk) than in the other breeds. Villafranquina and Buff Prat showed significantly lower cholesterol (14.54 +/- .26 and 14.56 +/- .26 mg/g yolk, respectively) than the White Leghorn (16.30 +/- .26 mg/g yolk). Eggs from the Vasca breed contained significantly more cholesterol (19.09 +/- .26 mg/g yolk) than did eggs laid by the other breeds, whereas no differences were found between Leghorn and Castellana. A negative heterosis percentage of -13% was found in the C x BP-F2 when compared with the parental breed means. The reduction in cholesterol concentration per egg observed in the C x BP-F2 (220.49 mg per egg) was not related to breed differences in egg weight or to the proportion of yolk per egg. Eggs from the Vasca breed, with the lightest yolk and smallest yolk: albumen ratio (P < .05), contained the highest amount of cholesterol (304.29 mg per egg). Eggs from the White Leghorn containing the second highest amount of cholesterol (275.63 mg per egg). Thus, the variation in cholesterol content per egg was not attributable to differences in the proportion of yolk.

Albumins↗
PubMed1998

Genetic analysis of three South African horse breeds.

Genetic variability at 7 blood-group and 10 biochemical genetic loci was examined in 3 South African horse breeds, the Nooitgedacht, Boerperd and Basuto Pony. Observed heterozygosity for these breeds was intermediate for domestic horses, with the highest heterozygosity in the Boerperd and the lowest in the Basuto Pony. The 3 breeds show greater genetic similarity to each other than to other domestic horse breeds. Compared to other breeds, the South African breeds show greater genetic similarity to breeds such as the Thoroughbred, Holstein, Trakehner and Hanovarian and also to North American breeds such as the Saddlebred, Standardbred and Morgan Horse.

Alleles↗
PubMed2003

Polymorphism of E. coli F18 receptor gene in different pig breeds.

The genetic variation of E. coli F18 receptor(ECF18R) loci in 867 pigs including Large Yorkshire, Landrace, Duroc, Ningxiang pig, Shaziling pig and Daweizi pig was detected by PCR-RFLP with Hin6 I. The results showed as follows: The three exotic breeds including Large Yorkshire, Landrace and Duroc were proved to be polymorphic at the Hin6 I-RFLP site. The average susceptibility genotype frequency of AG and GG in the exotic breeds was 0.94, G allelic frequency was 0.76. The C-->A mutation frequency at M307 site was very low in exotic breeds. The resistance genotype frequency of AA was 0.06. But the three native breeds including Ningxiang pig, Shaziling pig and Daweizi pig presented only GG genotype and no variation at the Hin6 I-RFLP site. The chi 2 value of ECF18R genotype distribution at the Hin6I-RFLP site in different pigs indicated that ECF18R genotype distribution of every exotic pig breed had significant or highly significant differences with three native pig breeds'. The ECF18R genotype distribution of three native pig breeds was the same completely. The others had no difference except that Landrace ECF18R genotype distribution had significant differences with Duroc's in the exotic breeds of pig.

Alleles↗
PubMed1989

Blastocyst development on days 10 or 14 after consumption of zearalenone by sows on days 7 to 10 after breeding.

Sixteen primiparous sows were bred and fed either a control ration (n = 8) or a diet containing purified zearalenone (n = 8; 1 mg/kg of body weight) from days 7 to 10 after breeding. On day 7 after breeding, the jugular vein of each sow was cannulated and blood was collected at 20-minute intervals for 4 hours before feeding and 4 hours after feeding. On day 10 after breeding, blood samples were collected from 4 control sows and 4 zearalenone-fed sows at 20-minute intervals for 4 hours before collection of blastocysts. A similar blood sampling schedule was followed for the remaining 4 control and 4 zearalenone sows on day 14 after breeding. On day 10 after breeding, spherical blastocysts were recovered from all control sows and from 3 of 4 zearalenone-treated sows. Average diameter of blastocysts from zearalenone-treated sows were similar to that of control sows. On day 14 after breeding, blastocysts were recovered from all control sows and 3 of 4 zearalenone-treated sows. Blastocysts from the control sows were filamentous, whereas blastocysts from zearalenone-treated sows were fragmented and contained foci of necrosis. Incidence of luteinizing hormone (LH) secretory spikes per sow was less (P less than 0.01) in zearalenone-treated sows (0.25 +/- 0.25/4 h) than control sows (1.75 +/- 0.25/4 h) on day 10 after breeding. Incidence of follicle-stimulating hormone (FSH) secretory spikes was similar (P = 0.45) among treatments on days 7, 10, and 14 after breeding.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1995

[Genetic structure of various native and commercial breeds of cattle (Bos taurus) from Eurasia].

On the basis of polymorphism of genes, controlling seven blood and four milk proteins, genetic structure and main variation parameters were analyzed in 27 breeds of cattle, 11 of which were native. Difference in allele frequencies of blood proteins were detected in the Jersey (island form) and Yakut (geographically isolated form) breeds; in milk proteins, the Yaroslavl' breed differed from the other breeds. Native breeds generally had a more specialized genetic structure than commercial breeds. They had a greater deficit of heterozygotes, which is probably related to the small number of individuals in this breed group and their high homozygosity. An analysis of inter- and intrapopulation diversity showed differences in groups of commercial and native breeds that depended on the intensity of selection in populations.

Animal Husbandry↗
PubMed1994

Characterization of Zebu cattle breeds in Tanzania using random amplified polymorphic DNA markers.

A total of 141 short primers, of arbitrary nucleotide sequence, were used singly in polymerase chain reactions to amplify DNA fingerprints in pools of DNA representing three Zebu cattle breeds. Two primers, which discriminated between the breed-specific DNA pools were used further to amplify individual pool components in order to establish band frequencies of the amplified fingerprints. One of the primers (ILO 1127) amplified a RAPD fingerprint in 61% of TSZ animals but less than 6% in the other breeds, while another primer (ILO 1065) revealed a DNA sequence common to 89% of the Boran animals and less than 30% in the other two breeds. Bandsharing and mean average percentage difference calculated within and between the three breeds using RAPD fingerprint data showed a higher degree of homogeneity within than across the breeds and indicated measurable divergence between the three breeds. It is concluded that RAPD polymorphisms are useful as genetic markers for cattle breed differentiation.

Animals↗