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Albatross populations in peril: a population trajectory for black-browed albatrosses at south Georgia.

Simulation modeling was used to reconstruct Black-browed Albatross (Diomedea melanophris) population trends. Close approximations to observed data were accomplished by annually varying survival rates, reproductive success, and probabilities of returning to breed given success in previous years. The temporal shift in annual values coincided with the start of longline fishing at South Georgia and potential changes in krill abundance. We used 23 years of demographic data from long-term studies of a breeding colony of this species at Bird Island, South Georgia, to validate our model. When we used annual parameter estimates for survival, reproductive success, and probabilities of returning to breed given success in previous years, our model trajectory closely followed the observed changes in breeding population size over time. Population growth rate was below replacement (lambda < 1) in most years and was most sensitive to changes in adult survival. This supports the recent IUCN uplisting of this species from "Vulnerable" to "Endangered." Comparison of pre-1988 and post-1988 demography (before and after the inception of a longline fishery in the breeding area) reveals a decrease in lambda from 0.963 to 0.910. A life table response experiment (LTRE) showed that this decline in lambda was caused mostly by declines in survival of adults. If 1988-1998 demographic rates are maintained, the model predicts a 98% chance of a population of fewer than 25 pairs within 78 years. For this population to recover to a status under which it could be "delisted," a 10% increase in survival of all age classes would be needed.

Animals↗

[Levels of toxic elements--Cd, Pb, Hg, Cr, Cu, Zn--in the blood and placenta of cows during parturition and in newborn calves].

It was demonstrated that mother's blood and the blood of new-born calves were contaminated by toxic elements in exposed and non-exposed area. The average Cd and Zn levels differed at high statistical significance (P less than 0.01) in the mothers blood from non-exposed regions in comparison with the average Cd and Zn levels from exposed region. The average residues of toxic elements in breeding cows placenta from the exposed and non-exposed regions were not statistically different. The average Zn content in new-born calves from non-exposed regions differ highly statistically significantly in comparison with the average Zn content in the blood of new-born calves from heifers of the exposed region. The transplacental ratio (TPx) of a toxic element in cow placenta during parturition was expressed from the average ratio of toxic element content in mother's blood: toxic element content in placenta: the toxic element content in blood of newborn calf, while the content of toxic element in mother's blood during parturition was expressed by a value equal to one. TPx in parturition period was expressed by mathematical formula TPx = 1 : Xp : Xk, where Xp = toxic element content in placenta, Xk = content of the toxic element in blood of new-born calf. TPPb, Hg, Cr, Cu, Zn values were not statistically different between the groups of breeding cows from exposed and non-exposed regions. TPCd in the group comprising 14 first-calves from the exposed region (TPCd = 1:0.89:2.59 in comparison with TPCd of six cows from non-exposed region, where TPCd = 1:0.29: 0.70;, differed statistically highly significantly (P less than .01). High statistical differences (P, less than 01) TPCd between these groups were explicitly affected highly statistically significantly (P less than .01) by different average Cd content in the blood of fourteen first-calves, compared with the average Cd content in blood of six cows from non-exposed region, in which the Cd value in blood during parturition was higher by 10(-1).

Animals↗

Distribution of plasma lipids and glucose in two breeds of rabbit.

This study was undertaken to determine the frequency distribution of plasma lipid and glucose values in New Zealand White and Dutch-Belted rabbits. The results indicate that the levels of glucose, phospholipid and triglyceride were similar in the two breeds in contrast to cholesterol levels which were higher and more variable in the New Zealand White rabbit. These results are consistent with the higher incidence of spontaneous aortic lesions and more varied response to dietary cholesterol in the New Zealand White rabbit. Identification of rabbits having higher than normal fasting cholesterol levels may be valuable in the design of studies of within strain differences in cholesterol metabolism. The study also provides a useful baseline using current methods for glucose and lipid levels in the two breeds of rabbit.

Animals↗

Semen quality in dogs and the influence of a short-interval second ejaculation.

Semen quality was examined in each of 65 known fertile dogs. Values were found to be similar to those previously published, although an apparent breed influence was demonstrated, with German shepherd dogs producing ejaculates of larger volume and greater total spermatozoal output than other breeds. A second ejaculate was collected from each dog with a mean interval of 63 min. The second samples had significantly lower values for the volume of the second fraction, the spermatozoal concentration and the total spermatozoal output. There were no differences for the percentage motility or the percentage of morphologically normal live spermatozoa. While there was no increase in semen quality of the second ejaculate, the technique may be useful since it results in the collection of approximately 70% more spermatozoa than a single ejaculate. These spermatozoa also had normal motility and morphology and could, therefore, be used for insemination or cryopreservation.

Animals↗

[Breeding of a biotype of Myzus persicae sulzer on a synthetic medium. V- Influence of oxalic and gentisic acids on the nutritive value of a synthetic medium].

Studies on the survival, fecundity, and food consumption by M. persicae reared on synthetic diets, have indicated: --gentisic and oxalic acids have a deleterious effect as most important as their dose is high. --succinic acid reduces, at least for the used concentrations, the deleterious effect of the oxalic acid, but not that of the gentisic acid. --gentisic acid is quickly decreasing food consumption. --the deleterious effect of oxalic and gentisic acids is not decreasing with time. The results are discussed in regard with the plant-aphid relations.

Animal Nutritional Physiological Phenomena↗

Fasting energy metabolism of the Yucatan miniature pig.

The fasting metabolic rates (FMR) of Yucatan miniature swine were determined using an open-circuit indirect respiration calorimeter. Mature nulliparous females had a mean FMR of 93 kcal/kg BW.75 and did not change significantly during the estrous cycle. This value is comparable to that observed in mature domestic swine. The calculated metabolizable energy requirement for maintenance for the Yucatan sow is 116 kcal/kg BW.75. Growing Yucatan boars had FMR of 127, 119 and 101 kcal/kg BW.75 at 15, 21 and 38 weeks of age, respectively, and were similar to values for comparably aged domestic swine. The calculated estimate for the metabolizable energy requirement for maintenance for Yucatan boars ranged from 158 kcal at 15 weeks of age to 126 kcal/kg BW.75 for 38 week old animals. Based on the similarity between the FMR of the Yucatan miniature swine in the present study and values published for standard size commercial hogs, it is concluded that the metabolic rates of these breeds of pig are similar. It is suggested that the daily energy needs of the Yucatan miniature pig may be met using values published for production livestock having similar physiological condition when adjusted for the smaller body size of the Yucatan breed.

Animals↗

Normative auditory brainstem response data for hearing threshold and neuro-otological diagnosis in the dog.

There is growing interest in the application of auditory brainstem response (ABR) audiometry for hearing assessment in dogs. The technique is far from standardised, however, resulting in large discrepancies between studies. This study aimed to obtain normative data, under clearly defined conditions, for two breeds of significantly different size; head size being a potential factor determining ABR latency values. The subjects, 20 dalmatians and 20 Jack Russell terriers, were sedated prior to ABR testing, and subcutaneous scalp electrodes used to detect the evoked potential elicited by a click stimulus presented via insert earphones. The mean ABR thresholds for the two breeds, 0 and -5 decibels re normal hearing level (dB nHL), respectively, were very similar to those for humans. The latency values of the main ABR waves and the interval between them were statistically significantly smaller for the smaller breed, but there was no correlation with head size within either breed. The results provide a baseline to assist with confirmation of hearing impairment and neuro-otological diagnosis in the dog.

Animals↗

Yearling trait comparisons among inbred lines and selected noninbred and randomly bred control groups of Rambouillet, Targhee and Columbia ewes.

Inbreeding with concurrent selection was used to develop 26 Rambouillet, 20 Targhee and 10 Columbia inbred lines of sheep. Inbreeding coefficients averaged 30, 29 and 30% for the three breeds, respectively, at the conclusion of the study. A selected noninbred control group and a randomly bred unselected control group were maintained for each breed. Yearling traits were evaluated for 545 Rambouillet, 572 Targhee and 411 Columbia yearling ewes, each belonging to one of the inbred lines or control groups. In each breed, the selected controls were generally of greatest overall merit, the unselected controls intermediate and the inbred lines of least merit. Only a few yearling traits of only a few inbred lines were superior (P less than .05) to those of their appropriate selected control groups. Selection within inbred lines was generally ineffective in offsetting inbreeding depression. However, single trait selection for traits of high heritability, notably yearling weight, clean fleece weight and staple length, appeared to compensate for inbreeding effects on those traits. Deleterious consequences of inbreeding were particularly apparent in yearling weight, average daily gain, type and condition scores, grease and clean fleece weights and index of overall merit. Inbreeding also resulted in fewer neck folds among inbreds of all three breeds. Correlations between the rankings of inbred lines at weaning and yearling ages were high for traits of higher heritability. Superiority of the selected controls in most traits was of about the same magnitude at weaning and yearling ages. In no case did the final overall merit (index value) of an inbred line of any of the three breeds significantly exceed the overall merit of its respective selected control group.

Age Factors↗

[Relation of lactose levels in milk and indicators of mammary gland health in the first third of lactation].

A total of 662 bucket milk samples from cows of two breed groups were examined: red and white breed = Bohemian Pied cattle with different genetic proportions of Ayrshire and Red Holstein improvement breeds; black and white breed = Black and White Lowland breed and different degree of absorptive crossing with a genetic proportion of the Holstein breed. Samples of daily milk yields were taken in the first three months of lactation once a month within a year. A possibility of using lactose content as an auxiliary indicator for detection of the mammary gland secretion disorders in the initial lactation stage was evaluated. The average values of the different indicators and their variability are summarized in Tab. I showing also the significance in a statistical model of included effects. Lactose content (L) was 4.88 +/- 0.20%, chloride content (Cl-) 113.7 +/- 22.4 mg/100 ml, somatic cell (SC) count 474 +/- 805 thousand/ml, SC count log corresponds to the geometrical mean of 234 thousand/ml, titratable acidity (SH) 7.34 +/- 0.83 x 2.5 mmol/l, chloride-lactose ratio (ClL) 2.27 +/- 0.51, conductivity (gamma) 442.4 +/- 34.5 mS/m and mastitis test (MT-NK) 0.72 +/- 1.18. The efficiency of the used statistical model was highest for Cl- content (Tab. I, R2 = 0.41), and it was lowest for SC counts (R2 = 0.07), while it increased to the twofold value (R2 = 0.15) after logarithmic transformation of SC counts. The breed group exerted a significant effect on Cl-, SC, log SC, SH, ClL, gamma and MT-NK (Tab. I). The breed group of red and white cows (Tab. II) had higher component contents and better indicators of the udder health state (Cl-, SC, log SC, ClL, gamma and MT-NK). The month of lactation influenced significantly SC, log SC, SH and gamma (Tab. I). A decrease in SC counts with the accruing month of lactation was observed (Tab. II), the trend of gamma and SH was opposite. The effect of lactation number was found to be significant for L, SC, log SC, SH, ClL, gamma and MT-NK (Tab. I). A tendency of a gradual decrease with the lactation number was observed in these indicators: L, SH, proteins and solids-non-fat (Fig. 1), while Cl-, gamma and ClL showed an opposite tendency. The year season influenced significantly L, log SC, SH, ClL, gamma and MT-NK (Tab. I, Fig. 2).(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

A quantitative genetic model of reciprocal altruism: a condition for kin or group selection to prevail.

A condition is derived for reciprocal altruism to evolve by kin or group selection. It is assumed that many additively acting genes of small effect and the environment determine the probability that an individual is a reciprocal altruist, as opposed to being unconditionally selfish. The particular form of reciprocal altruism considered is TIT FOR TAT, a strategy that involves being altruistic on the first encounter with another individual and doing whatever the other did on the previous encounter in subsequent encounters with the same individual. Encounters are restricted to individuals of the same generation belonging to the same kin or breeding group, but first encounters occur at random within that group. The number of individuals with which an individual interacts is assumed to be the same within any kin or breeding group. There are 1 + i expected encounters between two interacting individuals. On any encounter, it is assumed that an individual who behaves altruistically suffers a cost in personal fitness proportional to c while improving his partner's fitness by the same proportion of b. Then, the condition for kin or group selection to prevail is [Formula: see text] if group size is sufficiently large and the group mean and the within-group genotypic variance of the trait value (i.e., the probability of being a TIT-FOR-TAT strategist) are uncorrelated. Here, C, Vb, and Tb are the population mean, between-group variance, and between-group third central moment of the trait value and r is the correlation between the additive genotypic values of interacting kin or of individuals within the same breeding group. The right-hand side of the above inequality is monotone decreasing in C if we hold Tb/Vb constant, and kin and group selection become superfluous beyond a certain threshold value of C. The effect of finite group size is also considered in a kin-selection model.

Altruism↗

Frequency and distribution of alleles of canine MHC-II DLA-DQB1, DLA-DQA1 and DLA-DRB1 in 25 representative American Kennel Club breeds.

The frequency and distribution of dog leucocyte antigens (DLA) class II -DQA1, -DQB1 and -DRB1 alleles were determined for 25 American Kennel Club (AKC) registered dog breeds, representing 360 dogs from each of the seven major performance categories. Six to twenty-eight (average n=11) dogs were studied per group, with the exception of the Akita dog (n=94). All dogs were unrelated with no common grandparents based on AKC pedigree records (F-value <0.125). DLA class II allelic diversity was broad across breeds; 31/61 published DLA-DRB1 alleles, 11/18 published DLA-DQA1 alleles and 31/47 published DLA-DQB1 alleles were found among the 25 breeds. However, allelic diversity was severely limited within a breed. Seventeen of the DLA-DRB1 alleles were each found in only a single breed, and only seven alleles were shared by seven or more breeds. DLA-DRB1*00101 and DLA-DRB1*01501 were shared by 16 and 19 breeds, respectively. DLA-DQA1*00101 and DLA-DQA1*00601 alleles were shared by many breeds. The Rough Collie (DLA-DQA1*00901), English Setter (DLA-DQA1*00101) and Scottish Terrier (DLA-DQA1*00101) were monoallelic for DLA-DQA1. Eleven DLA-DQB1 alleles were each found only in a single breed and only seven alleles were shared by six or more breeds. DLA-DQB1*00201 and DLA-DQB1*02301 were shared by 17 and 18 breeds, respectively. Forty per cent of dogs typed were homozygous at DLA-DRB1, 52% at DLA-DQA1 and 44% at DLA-DQB1. Nine new DLA class II alleles were identified; three for DRB1 and six for DQB1. Comparison of our study of North American purebred dogs to previous European DLA surveys showed a similar use of common alleles consistent with known founder effects. However, more alleles were detected in European breeds, compared to their North American descendents, indicating that additional DLA class II diversity was lost when European breeds were established in North America.

Alleles↗

Microsatellite-based diversity analysis and genetic relationships of three Indian sheep breeds.

The genetic structure of three Indian sheep breeds from two different geographical locations (Nali, Chokla from north-western arid and semi-arid region; Garole from eastern saline marshy region) of India was investigated by means of 11 ovine-specific microsatellite markers as proposed in FAOs MoDAD programme. Microsatellite analysis revealed high allelic and gene diversity in all the three breeds. Nali sheep showed higher mean number of alleles and gene diversity (6.27 and 0.65) than Chokla (5.63 and 0.64) and Garole (5.63 and 0.59). High within population inbreeding estimates observed in the three breeds (FIS, Chokla = 0.286, Nali = 0.284, Garole = 0.227) reflected deficit of heterozygotes. The overall estimates for F-statistics were significantly (p < 0.05) different from zero. High values of FST (0.183) across all the loci revealed substantial degree of breed differentiation. Based on pair wise FST and Nm between different breeds, Nali and Chokla (FST = 6.62% and Nm = 4.80) were observed to be the closest followed by Garole and Nali (FST = 20.9% and Nm = 1.80), and Garole and Chokla (FST = 21.4% and Nm = 1.71). In addition, genetic distance estimates, phylogeny analysis and individual assignment test used to evaluate interbreed genetic proximity and population structure also revealed substantial genetic differentiation between Garole and the other two Rajasthani (Nali and Chokla) sheep. This divergent status of Garole sheep indicated genetic uniqueness of this breed suggesting higher priority for its conservation.

Animals↗

Uterine secretion from mares with post-breeding endometritis alters sperm motion characteristics in vitro.

Uterine secretion was collected from five normal mares during estrus by the use of a tampon. In subsequent estrus cycles, mares were inseminated with 1 x 10(9) spermatozoa from a stallion of known fertility, and uterine secretion was collected randomly at 6, 12, and 24 hours after insemination. All mares had negative endometrial cytology before insemination. At the time of uterine secretion sampling, semen was collected from two stallions and extended with Kenney's extender to a concentration of 50 x 10(6) spermatozoa/mL. Extended semen was diluted 2:1 with uterine secretion; semen extender; and centrifuged uterine secretion (noncellular). Samples were kept at room temperature and sperm motion characteristics (corrected motility (CMOT), progressively motile spermatozoa (PMS), and mean path velocity (MPV) were evaluated using a computer-assisted semen analyzer every 40 minutes for a total of 4 hours. Sperm motion characteristics of spermatozoa were significantly better when incubated in semen extender compared to uterine secretion (P < 0.05). The CMOT and PMS were significantly better in uterine secretion collected before, compared to after AI with the lowest values observed in samples collected at 12 hours after breeding (P < 0.05). Sperm motion characteristics of spermatozoa incubated in centrifuged uterine secretion was only slightly suppressed compared to spermatozoa incubated in semen extender, suggesting that the altered motion characteristics were mostly due to the presence of polymorphonuclear neutrophils (PMNs) in the samples. It was concluded from this study that spermatozoa can survive in inflamed uterine secretion, but that sperm motion characteristics in vitro are altered.

Animals↗

Genetic influences on reproduction of female red deer (Cervus elaphus) (2) seasonal and genetic effects on the superovulatory response to exogenous FSH.

This study evaluated the influences of seasons and genotype on the superovulatory response to a standardised oFSH regimen in red deer (Cervus elaphus scoticus) and its hybrids with either wapiti (C.e. nelsoni) or Père David's (PD) deer (Elaphurus davidianus). Adult red deer (n=9), F(1) hybrid wapiti x red deer (n=6), and maternal backcross hybrid PD x red deer (i.e., 14 PD hybrid; n=9) were kept together in the presence of a vasectomised stag for 13 months. At 6 weekly intervals, all hinds received a standardised treatment regimen used routinely to induce a superovulatory response in red deer hinds, with 10 consecutive treatments spanning an entire year. This involved synchronisation with intravaginal progesterone devices and delivery of multiple injections of oFSH (equivalent to 72 units NIH-FSH-S(1)). Laparoscopy to assess ovarian response was performed 6-7 days after the removal of the devices. Both season and genotype had significant effects on ovulation rate (OR) and total follicular stimulation (TFS) (P<0.05). For all the three genotypes, ovarian responses were highest from March to November (breeding season) and lowest in the period from December to January, inclusive. Mean OR for red deer hinds ranged from 3.7 to 1.8 during the breeding season, with no observable trend. All red deer hinds were anovulatory during December and January. A similar pattern occurred for 14 PD hybrids, although mean OR during the breeding seasons were twofold lower than for the red deer. For F(1) wapiti hybrids, the first two treatments in March and April resulted in the highest mean OR observed (15.6 and 11.7, respectively). Thereafter, mean values ranged between 6.3 and 4.7 for the remainder of the breeding season. Furthermore, mean OR of 3.0 and 0.5 were recorded in December and January, respectively. For the red deer and F(1) wapiti hybrids, between-hind variation in OR was not randomly distributed across the treatment dates, indicating that the individuals varied significantly in their ability to respond to oFSH, at least within a given season.In conclusion, the study has shown that relative to red deer, F(1) wapiti hybrid hinds exhibit a higher sensitivity to oFSH, whereas 14 PD hybrid hinds have a lower sensitivity. However, individual variation within genotype was very marked. A seasonal effect was apparent for all genotypes, although some F(1) wapiti hybrid hinds exhibited ovulatory responses throughout the year.

Administration, Intravaginal↗

[Normal values of the hematological, biochemical and enzymological indices of the donkey].

Studied were a total of 85 (33 male and 52 female) donkeys of the Martina Franca breed of the domestic ass, aged from one to twelve years. Stated are the results for the normal values of hemoglobin, hematocrit, ESR, total erythrocyte and leukocyte counts, leukocyte formula, blood sugar, cholesterin, urea, total protein and protein fractions, some micro- and macroelements, and enzymes as tabulated in four diagrams. No differences have been established with regard to sex. It has been found that with young animals the normal values of hemoglobin and erythrocytes are lower than with adult ones. With aging the total count of leukocytes shows a lowering trend, while the percent of neutrophiles rises. The lymphocyte profile of the white blood picture of this breed animals has been shown to be combined with eosinophilia. The amount of total protein with young donkeys is lower than with older ones, however, the albumin-globulin ratio remains unchanged. It is also stated that the concentration of inorganic phosphorus and calcium is in reverse correlation with the age of the animals--inorganic phosphorus is higher and calcium is lower in young animals, and vice versa. So far as the enzyme activity is concerned the values of the investigated enzymes are generally lower in donkeys than in horses.

Aging↗

Comparative hematological study of two breeds of foals (Andalusian and Arab) subjected to exercise of progressive intensity.

Exercise-induced hematological alterations were studied in 20 four-year old foals, 11 Andalusian and 9 Arabian. They were subjected to a test exercise program consisting of 4 levels of gradually increasing intensity (15, 20, 25 and 30 km/hr) with a duration of 5 min each. Blood samples were taken during resting, after each exercise level and at 10 and 30 min of recovery from exercise. The following hematic parameters were analyzed: red blood count, hematocrit value, hemoglobin, volumetric indexes (MCV, MCH and MHCH) and total plasma proteins. The alterations as a result of the physical effort were studied as well as any possible differences between the two breeds. The Arabian foals showed higher total plasma protein concentrations when resting, after each exercise level and at 10 mins of recovery time. The other variables studied remained with similar values in the two breeds without any significant changes.

Animals↗

An evaluation of genetic diversity indices of the Red Bororo and White Fulani cattle breeds with different molecular markers and their implications for current and future improvement options.

The genetic diversity of the Red Bororo and White Fulani cattle breeds of Cameroon and Nigeria was assessed with a panel of 32 markers. Estimates for the various indices of genetic diversity, total number of alleles (TNA), mean observed number of alleles (MNA), mean effective number of alleles (MNE), observed heterozygosity (Hob) and expected heterozygosity (Hex), were higher at microsatellite loci than at protein loci. Mean Hex values were above 71% at microsatellite loci in all the breeds and ranged from 37% to 41.6% at milk protein loci and from 40.9% to 45.6% at blood protein loci. The highest TNA and MNA of microsatellites were recorded for the Nigerian White Fulani. MNE of milk protein loci was highest in the Cameroonian Red Bororo, while TNA of blood protein loci was highest in the Cameroonian White Fulani. The high genetic diversity levels indicate the presence of the necessary ingredients for improvement breeding and conservation. Multi-locus estimates of within-population inbreeding (f), total inbreeding (F) and population differentiation (theta) of the breeds were significantly different from zero, except for theta of blood proteins. A high level of gene flow was found between the breeds (5.829). The phylogenetic relationship existing among the four breeds is greatly influenced by location. The high gene flow between the breeds may lead to a loss of genetic diversity through genetic uniformity and a reduction in opportunities for future breed development. We propose an improvement scheme with aims to prevent loss of genetic diversity, improve productivity and reduce uncontrolled genetic exchanges between breeds.

Alleles↗

[Hematologic values of crossbred dogs supplied by VELAZ].

The results of the determination of the complete haemogram, osmotic resistance, and sedimentation of erythrocytes of 21 intact crossbred experimental dogs purchased and supplied by the Laboratory Animal Breeding Enterprise are presented, and these results are compared with the corresponding average values of the same parameters calculated from literary data. The obtained starting values of the experimental groups or the values of the control groups of these animals are regarded as normal when the comparison with the calculated standard--including standard deviation--shows that these values range within the limits set just by two standard deviations.

Animals↗