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At least 721 records · Page 40Linked to original sources
PubMed1984

Sire breed effects in matings with Angus cows: I. Fertility, calf survival and performance to 18 months.

Over six calf crops, 524 exposures of Angus cows to three sire breeds resulted in 432 weaned calves for an 82.4% calf crop. Least-squares means for weaning rate by sire breed were 81.8, 80.5 and 83.9% for Angus, Charolais and Holsteins, respectively. Sire breed effect was not significant for calving rate, calf mortality or overall weaning rate, but was significant for all growth traits from birth to 18 mo. Angus-sired calves were smallest at birth, grew at a slower rate and were lightest in weight at all ages. Charolais-sired calves were heaviest at all weigh periods and Holstein-sired calves were intermediate. Holstein-sired calves scored significantly lower for both grade and condition than did Angus- and Charolais-sired calves. Charolais-sired calves had the highest grade. Calving rate tended to be influenced by the effect of cow (P less than .10) and sire breed X year (P less than .001). Calving rate was highest for 3-yr-old and for 6- to 10-yr-old cows and was also 1.5 percentage units higher for crossbred matings. Cow productivity (kg of calf weaned/cow exposed) is a combined measure of fertility, calf survival and weaning weight. Although sire breed did not significantly affect cow productivity (P less than .20), actual values favored cows producing crossbred calves by 14 and 9 kg for Charolais and Holstein crosses, respectively. Likewise, weight differences at 18 mo favored these crosses by 50 and 32 kg for heifers and 72 and 62 kg for steers. Among the two crossbred types, Charolais X Angus heifers were 28 kg heavier (P less than .05) than Holstein X Angus heifers at 18 mo but the 10 kg difference in steers was not significant. The fact that the large sire breeds produced calves with heavier weaning weights without demonstrating significant increases in overall productivity points out the importance of high weaning rates.

Animals↗
PubMed1985

Characterization of breeds of Bos indicus and Bos taurus cattle for maternal and individual traits.

Angus, Boran and Red Poll sires were mated to Ankole, Boran and small East African Zebu (Zebu) females to produce the cows characterized in this study, which produced calves by Friesian, Brown Swiss, Simmental, Boran and Red Poll sires. Individual traits included cow parturition weight, cow weight at weaning, cow mean weight and cow weight change from parturition to weaning; maternal traits included calf crop born percentage, preweaning viability percentage, overall viability percentage, birth weight, weaning weight, weight at 12, 18 and 24 mo and calf weight weaned per cow exposed to breeding (productivity index). Cows by Angus and Red Poll sires significantly exceeded cows by Boran sires (all cows in this comparison had Ankole and Zebu dams) in weaning weight of progeny and in cow weight at parturition and at weaning. Cows by Red Poll sires significantly exceeded cows by Boran sires in birth weight of progeny. Progeny of cows by Boran sires significantly exceeded progeny of cows by Angus and Red Poll sires in 24-mo weight. Cows by Angus and Red Poll sires did not differ (P greater than .05) in any of the traits analyzed. Cows with Ankole and Boran dams significantly exceeded cows with Zebu dams (all cows in this comparison had Angus and Red Poll sires) in progeny weight at birth, 18 mo and 24 mo and in cow weight at parturition and at weaning. Cows with Boran dams significantly exceeded cows with Zebu dams in weaning and 12-mo weight of progeny and significantly exceeded cows with Ankole dams in weaning weight of progeny. The significantly heavier weaning weight and significantly lighter 24-mo weight of the 3/4 Bos taurus progeny of cows with Angus and Red Poll sires relative to the 1/2 Bos taurus progeny of cows with Boran sires suggest that cattle that are 1/2 Bos taurus breed composition have greater general adaptation than cattle with 3/4 Bos taurus breed composition in the postweaning nutritive and climatic environment under which this experiment was conducted. Significantly heavier weights of Angus and Red Poll crossbred cows relative to Boran crossbred cows (all breeds crossed on Ankole and Zebu cows) indicate that the two Bos taurus breeds exceed the Boran (Bos indicus) breed in additive direct genetic effects for size when they have general adaptation to the environment.

Acclimatization↗
PubMed1987

Cow breeding and calf growth performance as affected by pregnancy status the previous year.

A 2-yr study was conducted to compare the subsequent cow breeding and calf performance of cows that were nonpregnant with cows that were pregnant at the time calves were weaned. Cows were Angus (A), Polled Hereford (PH), Santa Gertrudis (SG) straightbreds and crossbreds of these breeds. Nonpregnant cows (G1) were 4- to 9-yr-olds that had a calf the previous year and appeared to be physically sound with no detection (by rectal palpation) of an abnormal reproductive tract due to disease, abnormal growth or calving difficulties. Pregnant cows (G2) were of similar age and breed composition to G1 cows. The 93 G1 and the 193 G2 cows were assigned within age and breed composition to sire breeding groups on pasture in an approximate 1:2 ratio, respectively, per sire. There were six A, three PH and one SG sires. The year prior to G1 cows being nonpregnant, G1 cows calved 11 d later (P less than .01) than G2 cows. Subsequent to their being nonpregnant, G1 cows gained 27 kg more (P less than .001) weight during the breeding period, had 5.4 percentage units more (P less than .29) calves born, had calves 17 d earlier (P less than .001) in the calving period, had calves that gained at a similar rate to weaning and had calves that were 14 kg heavier (P less than .01) at weaning (due to their being 17 d older) compared with G2 cows and calves.

Analysis of Variance↗
PubMed1999

Short communication: lack of breed differences in responses of bovine spermatozoa to heat shock.

An experiment was conducted to test whether the magnitude of effects of heat shock on spermatozoal function were less for thermotolerant breeds (Brahman and other breeds with Brahman influence) than for breeds that evolved in northern Europe (Angus and Holstein). Frozen spermatozoa were thawed, purified by Percoll gradient centrifugation and incubated at 38.5, 41, or 42 degrees C for 4 h. Sperm motility was then analyzed with a Hamilton Thorn Motility Analyzer. Heat shock reduced the percentage of sperm that were motile, mean track speed, and mean path velocity. There were no significant breed x temperature interactions for these traits. The mean frequency of tail beat tended to be reduced by heat shock in bulls of Brahman-influenced breeds and, to a lesser extent, in Brahman bulls, but it was not affected by heat shock in Angus or Holstein bulls. For no traits were there significant temperature x bull within breed interactions. Overall, results indicate that 1) heat shock reduces motility of bovine spermatozoa and 2) genetic effects are unlikely to be an important determinant of the function of ejaculated sperm following heat shock.

Animals↗
PubMed1992

Effect of feed allowance during rearing and breeding on female broiler breeders. 2. Ovarian morphology and production.

The influence of feed allowance during rearing (4 to 18 wk) and breeding (18 to 62 wk) on ovarian morphology and egg production was examined. During rearing, beginning at 4 wk of age, 400 Indian River pullets that had been full-fed from 1 day of age either continued to be full-fed (F, n = 200) or were feed restricted (R, n = 200), following commercial practice. At 18 wk of age, 100 birds (within +15% of the mean BW) in each of F and R rearing groups were further assigned to be full-fed (n = 50) or feed restricted (n = 50) during breeding. Thus, based on feed allowance during rearing and breeding, four treatment groups were formed (FF, FR, RF, and RR). Feed restriction during rearing significantly delayed oviduct development and age at sexual maturity (age at first egg). Compared with feed restriction during both rearing and breeding (RR), ad libitum feeding beginning at 18 wk of age (RF) significantly increased the weight of the ovary and the number of large follicles at sexual maturity but did not significantly affect the age at sexual maturity. Feed restriction during rearing, breeding, or both significantly reduced the incidence of erratic ovipositions, defective eggs, and multiple ovulations. The incidence of erratic ovipositions was positively correlated (r = .692, P less than or equal to .001) with the laying of soft-shelled and shell-less eggs and negatively correlated (r = -.508, P less than or equal to .001) with the production of settable eggs to 62 wk of age. Compared with ad libitum feeding, controlled feeding during breeding significantly improved both settable and total egg production. Among the four feeding regimens, Treatment RR resulted in the highest fertility and hatchability.

Aging↗
PubMed1998

[Comparative analysis of Ayrshire and Black Pied cattle breeds by histocompatibility markers].

Distribution of BoLA-A antigens and BoLA-DRB3 alleles was studied by means of the microlymphocytotoxic test (BoLA-A) and the PCR-RFLP method (BoLA-DRB3) using restriction endonucleases RSAI, HaeIII, and XhoII in Ayrshire (n = 127) and Black Pied (n = 129) cattle breeds. Comparative analysis of profiles for class I antigens revealed significant differences in the frequencies of antigens W2, W6, W10, W31, W44, W15, and W19 (P > 99%). The studied breeds also differ in the spectrum of BoLA-DRB3 alleles and distribution of their frequencies. Heterogeneous allele frequency profile was detected in Ayrshire cattle: five of 18 detected alleles (DRB3.2*7, *8, *10, *24, and *28) accounted for 77%. Allele DRB3.2*7 (37.6%), which is classed with rare alleles in Black Pied cattle is the most common in Ayrshire cattle. The observed heterozygosity level in the combined sample of Black Pied breed (0.836) is higher than in Ayrshire breed (0.070). In both breeds, the heterozygosity level was studied in the groups of healthy and ill with persistent lymphocytosis (caused by bovine leukemia virus) animals and in the group of virus carriers in Ayrshire breed. In ill animals, a decrease in the observed heterozygosity level was detected, as compared to healthy animals and the expected heterozygosity level. The observed heterozygosity level exceeds the expected one in virus carriers. The detected features of the heterozygosity level in the studied groups allow the heterozygosity level for locus BoLA-DRB3 to be considered a nonspecific factor of resistance to leukemia and are heterozygous animals to have higher resistance to bovine leukemia. The presence of a larger proportion of highly productive animals (the annual productivity of more than 7000 kg) in the group of ill Ayrshire cattle animals, as compared to healthy animals to established. To increase resistance to bovine leukemia, the obtained data indicate the importance of the control of heterozygosity level and genetic diversity for gene BoLA-DRB3 in cattle herds.

Alleles↗
PubMed2000

The effects of breed and level of nutrition on whole-body and muscle protein metabolism in pure-bred Aberdeen angus and Charolais beef steers.

Eighteen pure-bred steers (live weight 350 kg) from each of two breeds, Aberdeen Angus (AA) and Charolais (CH), were split into three equal groups (six animals each) and offered three planes of nutrition during a 20-week period. The same ration formulation was offered to all animals with amounts adjusted at 3-week intervals to give predicted average weight gains of either 1.0 kg/d (M/M group) or 1.4 kg/d (H/H group). The remaining group (M/H) were offered the same amount of ration as the M/M group until 10 weeks before slaughter when the ration was increased to H. Data on animal performance, carcass characteristics and fibre-type composition in skeletal muscle are presented elsewhere (Maltin et al. 2000; Sinclair et al. 2000). On three occasions (17, 10 and 2 weeks before slaughter) the animals were transferred to metabolism stalls for 1 week, during which total urine collection for quantification of Ntau-methylhistidine (Ntau-MeH) elimination was performed for 4 d. On the last day, animals were infused for 11 h with [2H5]phenylalanine with frequent blood sampling (to allow determination of whole-body phenylalanine flux) followed by biopsies from m. longissimus lumborum and m. vastus lateralis to determine the fractional synthesis rate of mixed muscle protein. For both breeds, the absolute amount of Ntau-MeH eliminated increased with animal age or weight (P < 0.001) and was significantly greater for CH steers, at all intake comparisons, than for AA (P < 0.001). Estimates of fractional muscle breakdown rate (FBR; calculated from Ntau-MeH elimination and based on skeletal muscle as a fixed fraction of live weight) showed an age (or weight) decline for M/M and H/H groups of both breeds (P < 0.001). FBR was greater for the H/H group (P = 0.044). The M/H group also showed a lower FBR for the first two measurement periods (both at M intake) but increased when intake was raised to H. When allowance was made for differences in lean content (calculated from fat scores and eye muscle area in carcasses at the end of period 3), there were significant differences in muscle FBR with intake (P = 0.012) but not between breed. Whole-body protein flux (WBPF; g/d) based on plasma phenylalanine kinetics increased with age or weight (P < 0.001) and was similar between breeds. The WBPF was lower for M/M compared with H/H (P < 0.001) based on either total or per kg live weight0.75. Muscle protein fractional synthesis rate (FSR) declined with age for both breeds and tended to be higher at H/H compared with M intakes (intake x period effects, P < 0.05). Changing intake from M to H caused a significant increase (P < 0.001) in FSR. The FSR values for AA were significantly greater than for CH at comparable ages (P = 0. 044). Although FSR and FBR responded to nutrition, these changes in protein metabolism were not reflected in differences in meat eating quality (Sinclair et al. 2000).

Age Factors↗
PubMed1996

Identifying yield-optimizing environments for two cowpea breeding lines by manipulating photoperiod and harvest scenario.

Photoperiod and harvest scenario of cowpea (Vigna unguiculata L. Walp) canopies were manipulated to optimize productivity for use in future controlled ecological life-support systems. Productivity was measured by edible yield rate (EYR:g m-2 day-1), shoot harvest index (SHI: g edible biomass [g total shoot dry weight]), and yield-efficiency rate (YER:g edible biomass m-2 day-1 per[g nonedible shoot dry weight]). Breeding lines 'IT84S-2246' (S-2246) and "IT82D-889' (D-889) were grown in a greenhouse under 8-, 12-, or 24-h photoperiods. S-2246 was short-day and D-889 was day-neutral for flowering. Under each photoperiod, cowpeas were harvested either for leaves only, seeds only, or leaves plus seeds (mixed harvest). Photoperiod did not affect EYR of either breeding line for any harvest scenario tested. Averaged over both breeding lines, seed harvest gave the highest EYR at 6.7 g m-2 day-1. The highest SHI (65%) and YER (94 mg m-2 day-1 g-1) were achieved for leaf-only harvest of D-889 under an 8-h photoperiod. For leaf-only harvest of S-2246, both SHI and YER increased with increasing photoperiod, but declined for seed-only and mixed harvests. However, photoperiod had no effect on SHI or YER for D-889 for any harvest scenario. A second experiment utilized the short-day cowpea breeding line 'IT89KD-288' (D-288) and the day-neutral breeding line 'IT87D-941-1' (D-941) to compare yield parameters using photoperiod extension under differing lamp types. This experiment confirmed the photoperiod responses of D-889 and S-2246 to a mixed-harvest scenario and indicated that daylength extension with higher irradiance from high pressure sodium lamps further suppressed EYR, SHI, and YER of the short-day breeding line D-288.

Agriculture↗
PubMed2002

[Research on genetic variation of heart fatty acid-binding protein gene in ten pig breeds].

The genetic variation of heart fatty acid-binding protein (H-FABP) gene in 561 pigs including Duroc, Landrace, Large Yorkshire, Nanchang white pig, Erhualian, Meishan, Yushan black pig, Leping spotted pig, Jinhua black head-hind pig and Shanggao black head-hind pig were detected by PCR-RFLP with Hinf I, Hae III and Msp I. The results showed as follows: (1) Nanchang white pig presented only HH genotype while other breeds varied at the Hinf I-RFLP site; (2) The exotic breeds including Duroc, Landrace, Large Yorkshire and the native breed Nanchang white pig were proved to be polymorphic while the five Chinese local breeds presented no variation at the Hae III-RFLP site; (3) Among the tested breeds only Duroc presented variation at the Msp I-RFLP site. It is noted that all the Chinese local breeds present as AADD--genotypes.

Animals↗
PubMed1975

Histochemical studies on the mucosubstances in the ovotestis of a hermaphrodite land pulmonate Semperula maculata in seasonal breeding-aestivation cycle.

With a view to augment the cytochemical localization characterization and, probable functional significance of mucosubstances in the ovotestis in the reproductive physiology of land pulmonates, the mucosubstances were investigated in the ovotestis of a land snail, Semperula maculata (Stylommatophora) in the seasonal breeding-aestivation cycle. Widely accepted, recent and well-established histochemical techniques were emoloyed. The results showed that the cells in the germinal epithelium of the follicular wall, were endowed with a capacity of synthesis of neutral muco-substances. They also contained glycogen. The nurse cells contained neutral mucosubstances and glycogen in them, while maturing ovum contained hyaluronic acid and protein. Among all the male germ cell stages, only matured sperms showed sialoglycoprotein in their heads and glycogen in the tails. The seasonal variations in the mucosubstances showed that the synthesis of the mucosubstances in the male germ cells of the ovotestis was initiated at the end of the breeding season and attained a maximum in the post-breeding season. Most strikingly the presence of the sperm in the follicular cavity was a permanent feature throughout the seasonal breeding-aestivation cycle of the snails. The synthesis of the mucosubstances in the ovum and the nurse cells was initiated somewhat earlier in the post-breeding season and attained a peak prior to the active breeding season. The importance of the mucosubstances synthesised by the different cells of the ovotestis, is discussed with reference to the reproductive physiology of the snails.

Animals↗
PubMed2005

Genetic variation of Polish endangered Biłgoraj horses and two common horse breeds in microsatellite loci.

Genetic variation of endangered Biłgoraj horses and two common Polish horse breeds was compared with the use of 12 microsatellite loci (AHT4, AHT5, ASB2, HMS2, HMS3, HMS6, HMS7, HTG4, HTG6, HTG7, HTG10, VHL20). Lower allelic diversity was detected in all investigated populations in comparison to other studies. Large differences in the frequencies of microsatellite alleles between Biłgoraj horses and two other horse breeds were discovered. In all polymorphic loci all investigated breeds were in the Hardy-Weinberg equilibrium. Mean Fis values and the results of a test for the presence of a recent bottleneck were non-significant in all studied populations. Comparable values of observed and expected gene diversity indicate no substantial loss of genetic variation in the Biłgoraj population and two other breeds. The lowest variability observed in the investigated group of Thoroughbred horses was confirmed. About 10% of genetic variation are explained by differences between breeds. Values of pairwise Fst and two measures of genetic distance demonstrated that Biłgoraj horses are distantly related to both common horse breeds.

Animals↗
PubMed1992

[Genetic differentiation between breeds of horses by polymorphic blood protein loci].

The estimation of genetic differentiation between 27 horses breeds originated in USSR, based on serum proteins polymorphism (loci Tf, Al, Es) is shown. Genetical variability among aborigine breeds is higher then among cultural ones. The erosion of gene pool of Przewalski's Horse is explained by special history of this population and a few horses in analyzing group. Genetic distances reflect the directions and intensity of breeding. High genetical distances between Przewalski's Horse, Shetland Pony and other horses obtained could be explained by overcoming the "bottle neck" of selections in breeding process. Results of investigation shown that 9 aborigine breeds of USSR are clustered in a special group, differed from foreign horse breeds, because their gene pool was quite unique.

Animals↗
PubMed2006

[Genetic diversity of mitochondrial DNA D-loop sequences in cattle breeds in Guizhou].

The complete mitochondrial D-loop sequences, 910 bp in length, in 82 individual cattle from 4 breeds in Guizhou province were analyzed. The results revealed 31 mitochondrial haplotypes, 65 polymorphic sites, covering 7.14% of the entire length of the sequence. Among these polymorphic sites, there were 62 transitions, 2 transversions and 1 coexistent site of transition and transversion. The nucleotide diversity (pi value) and haplotype diversity (H) estimated from mtDNA D-loop region in 4 cattle breeds in Guizhou varied from 2.16%-2.61% and 0.695-0.909, respectively, showing that abundant mitochondrial genetic diversity exists in Guizhou cattle breeds. The Neighbor-Joining molecular phylogenetic tree of mtDNA D-loop of 4 Guizhou cattle breeds was constructed according to the 31 haplotypes. The NJ tree indicated that the origin of cattle breeds was from Bos taurus and Bos indicus which had nearly the same influence on cattle breeds in Guizhou. The feasibility of applying nucleotide diversity (pi value) to the evaluation of bovine genetic differentiation was discussed.

Animals↗
PubMed2006

[Molecular characteristic marker method of 27 breeds of common Umbelliferae Chinese herb medicinal plants by sequencing rDNA].

OBJECTIVE: To probe a molecular marker method of accrediting fingerprinting of 27 kinds of common Umbelliferae Chinese herb medicinal plants by sequencing rDNA. METHOD: The rDNA sequences of the 27 breeds of common Umbelliferae Chinese herb medicinal plants were amplified, and were digested by restriction endonuclease, and were seperated via polypropylene electrophoresis, at last 6 breeds of them were sequenced. RESULTS: The rDNA sequence fragment we gained concluded ITS1, ITS2, 5.8S complete sequence and 18S, 26S part sequence. On the electrophoresis map of PCR products digested by restriction endonuclease MSP I, 27 breeds appeared 16 kinds of characteristic map, 11 of them differ from others; and PCR products digested by restriction endonuclease HaeIII, there appeared 5 kinds of characteristic map among 27 breeds, 3 of them differ from others. The sequenced result of 6 breeds showed genes whose length extented from 652bp to 656bp were acquired. These sequences of 3 breeds which showed the same electrophoresis map after digested by restriction endonuclease HaeIII exhibited great similarity according to similar phylogenetic tree constructed on rDNA sequence. CONCLUSION: The rDNA sequence character is effective molecular marker for classifying the different Umbellerae Chinese herb medicinal plants. And the method of sequencing rDNA surpassed that of restriction fragment long polymorphism (RFLP).

Angelica sinensis↗
PubMed1978

Problems of bovine leucosis control and prophylaxis in industrial breeding conditions.

Industrial cattle-breeding in Bulgaria is characterized by large cattle-breeding complexes holding 500, 1,000 or 2,000 dairy cows; farms specialized in rearing calves for breeding purposes, and calves fattening units holding 2,000, 5,000 or 10,000 animals. A specific technology has been introduced for management purposes. This high concentration and specialization creates specific organisational problems for antiepizootic control measures. Bovine leucosis has been brought from abroad by imported breedings animals. A complex system for leucosis prophylaxis and control is obligatorily implemented. It is supervized and financed by the state. Particular care is taken of ensuring protective measures for import breeding animals. The infected farms are put under strict quarantine. The animals which show a positive reaction during complex diagnostic tests are slaughtered and the meat is used after heat-processing. The milk is heat-processed too and sent for further utilization. Calves born in infected farms are not fit for breeding purposes but for fattening only.

Animals↗
PubMed1989

Mosquito breeding in rice fields and its role in malaria transmission in Mandla district, M.P.

A study of the breeding of mosquitoes in the rice field agro-ecosystem was carried out in Mandla district during 1987 and 1988. Results revealed that mosquito breeding commences in July and ends in October. Mosquito breeding in rice fields is inversely proportional to the distance from village. A. culicifacies breeds in rice fields up to a plant height of 20 cm and then gradually declines and becomes scarce, and is taken over by A. theobaldi and A. splendidus. A. fluviatilis breeds in irrigation channels almost throughout the rice growing season. There were a large number of other mosquito breeding sites which increased enormously with the onset of rains. The precise role of rice fields in maintaining high malaria transmission could not be established but the rice field agro-ecosystem contributed significant vector populations.

Adult↗
PubMed1989

Breed differences in plasma calcium, phosphorus and magnesium concentrations of Merino, Dohne Merino and S.A. Mutton Merino sheep with relation to the bent-leg syndrome.

Plasma calcium, phosphorus and magnesium concentrations were determined in ewes and their single and twin lambs from birth for 120 days in Merino, Dohne Merino and South African Mutton Merino sheep. Mineral concentrations as well as the plasma calcium: phosphorus ratio were compared between breeds. Throughout the experimental period, plasma calcium and phosphorus concentrations were higher in both single and twin lambs than in the ewes of all 3 breeds. No breed differences in plasma calcium concentrations were found. Animals of the S.A. Mutton Merino breed had significantly higher (P less than 0.05) plasma phosphorus concentrations than the other 2 breeds. The plasma Ca:P ratio in the Merino and Dohne Merino ram lambs was approximately 1.1:1 and in the S.A. Mutton Merino 0.9:1. This converse plasma Ca:P ratio found in both the S.A. Mutton Merino ewes and lambs is believed to result in an induced plasma ionised calcium deficiency which leads to improper calcification of bone. This is believed to be a contributing factor in the bent-leg syndrome. No difference was recorded in body mass between ram lambs suffering from the bent-leg syndrome and unaffected ram lambs. Plasma magnesium concentrations were not affected by breed or age of the animals.

Animals↗
PubMed1987

Clinical chemistry reference values in two breeds of swine and their changes during percutaneous exposure to soman.

Clinical chemistry reference values in blood from 48 nonfasting Chester White/Yorkshire and 48 Hanford Miniature swine were determined. Subsequently, 40 animals of each breed were restrained in a cloth sling and fasted for 24 hours while exposed percutaneously to pinacolyl methylphosphonofluoridate (soman). The range of dosages for the Hanford Miniature swine was 2.0 to 15.8 mg/kg, and for the Chester White/Yorkshire swine, the range was 4.0 to 25.0 mg/kg. Sham-exposed groups, consisting of 8 animals of each breed, were treated in an identical manner, except no anticholinesterase agent was administered. Samples of blood were drawn at 1, 7, 14, and 28 days after soman or sham exposure. In the sham-exposed groups, significant changes from the reference values were observed as a result of the 24-hour restraint. In both breeds, skeletal muscle enzyme activities were increased, plasma cholinesterase activity (ChEPL) was decreased, calcium concentration was decreased, and phosphorus concentration was increased. Percutaneous exposure to soman resulted in decreases of ChEPL and erythrocyte cholinesterase activities (ChERBC). The ChEPL recovered more quickly than the ChERBC in both breeds. Even in asymptomatic swine, the decrease of ChERBC was greater than 60% after 24 hours. In the swine of each breed given the largest dosage, hyperglycemia was apparent in blood samples taken at the onset of apnea, especially when the animal survived for greater than 2 hours. We conclude that both breeds of swine, on the basis of dispersion in clinical chemistry reference values, were equally suited for this type of dermatotoxicity study. The sling method of restraint, however, caused some undesirable changes in biochemical values.

Animals↗