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PubMed1998

Study on exposure of pig farm workers to bioaerosols, immunologic reactivity and health effects.

Occupational inhalation of organic dust may be a cause of numerous symptoms and diseases. Organic dust consists of various biological compounds which induce inflammatory reactions in the lungs on an immunotoxic or allergic basis. Bacteria and their metabolites, moulds and their spores, mycotoxins, glucans, and other still unidentified substances, can be potential aetiologic factors of diseases caused by organic dust. The aim of this study was to determine the concentration and composition of airborne microflora in typical Polish swine buildings and to assess the health conditions of the workers employed within them. Total concentration of microorganisms in the air of five examined swine breeding farms ranged from 613.7-1246.7 x 10(3) cfu/m3 (mean value 930.6 x 10(3) cfu/ m3). The examination of 53 employees working in the swine buildings included their medical history, physical examination, spirometry, and allergological tests. Work-related symptoms were reported by 31 (58.5%) of the subjects. No abnormal findings were present upon physical and spirometric examinations. The results suggest the common occurrence of work-related respiratory disease in swine workers, mostly corresponding to the Organic Dust Toxic Syndrome (ODTS).

Adult↗
PubMed1979

Plasma biochemical values of clinically-normal Australian sea lions (Neophoca cinerea).

Seventeen biochemical constituents were assayed in the blood plasma of clinically-normal Australian sea lions (Neophoca cinerea). The sea lions formed part of a breeding colony which inhabits the southern coast of Kangaroo Island, South Australia. Little variation was found in any of the values obtained from animals of different age and sex. The results were compared with values published for California sea lions (Zalophus californianus), Northern fur seals (Callorhinus ursinus), Harbor seals (Phoca vitulina) and Northern elephant seals (Mirounga angustirostris).

Animals↗
PubMed2002

Genetic and phenotypic relationships among endocrine and traditional fertility traits and production traits in Holstein-Friesian dairy cows.

The objective of this study was to estimate the heritability of a number of traditional and endocrine fertility traits in addition to d-56 predicted milk yield (MY56), and the genetic and phenotypic correlations between these traits. Various fixed effects such as season, year, herd, lactation number, diet, percentage Holstein (PCH) of the cow, and occurrence of uterine infection (UI), dystocia (DYS), and retained placenta (RP) were also investigated. Data collected for 1212 lactations of 1080 postpartum (PP) Holstein-Friesian dairy cows in eight commercial farms between 1996 and 1999 included thrice weekly milk progesterone samples, calving and insemination dates, various reproductive health records, monthly/bimonthly production records, three-generation pedigrees, and PCH information. Genetic models were fitted to the data to obtain heritabilitites and correlations using ASREML. Estimates of heritability for interval to commencement of luteal activity PP (lnCLA), length of the first luteal phase PP (lnLutI) and occurrence of persistent CL type I (PCLI) were 0.16, 0.17, and 0.13, respectively. Heritabilities for pregnancy to first service (PFS), interval to first service (IFS), and MY56 were 0.14, 0.13, and 0.50, respectively. Genetic regressions of lnCLA and lnLutI on PTA of the sire for milk, fat, and protein yields, and PIN95 were investigated. Regressions of lnCLA were positive and significant on fat yield, while regressions of lnLutI on both protein yield and PIN95 were negative and significant. Genetic correlations of endocrine fertility traits (lnCLA, lnLutI, and PCLI) with MY56 were high (0.36, P < 0.05; -0.51, P < 0.05; and -0.31, P < 0.1, respectively). Percentage Holstein of the cows had no significant effect on any of the fertility parameters monitored. This work emphasizes the strong genetic correlation of fertility with production traits and, therefore, highlights the urgent requirement for selective breeding for fertility in the United Kingdom. The high heritability of endocrine fertility traits stress their potential value for inclusion in a selection index to improve fertility.

Animals↗
PubMed1994

Haematology and biochemistry reference values for sows kept under modern management conditions.

The data presented here were obtained using blood samples from 159 healthy, conventionally managed sows from 37 breeding herds. Sows were sampled at weaning and at 4-5 weeks gestation. Paired blood samples were analysed from sows that had a normal pregnancy and subsequently farrowed. The mean values of serum total protein, albumin and gamma globulin concentration were lower in the blood samples obtained at weaning compared with those obtained at 4-5 weeks gestation. Leucocyte count was higher, mostly as a result of a higher segmented neutrophil count, in the blood samples obtained at weaning compared with those obtained at 4-5 weeks gestation.

Animal Husbandry↗
PubMed2005

Genetic structure and differentiation of 12 African Bos indicus and Bos taurus cattle breeds, inferred from protein and microsatellite polymorphisms.

Level of genetic differentiation, gene flow and genetic structuring of nine Bos indicus and three Bos taurus cattle breeds in Cameroon and Nigeria were estimated using the genetic information from 16 microsatellite, five blood protein and seven milk protein markers. The global heterozygote deficit across all populations (Fit) amounted to 11.7% (p < 0.001). The overall significant (p < 0.001) deficit of heterozygotes because of inbreeding within breeds (Fis) amounted to 6.1%. The breeds were moderately differentiated (Fst = 6%, p < 0.001) with all loci except CSN1S2 contributing significantly to the Fst value. The 12 populations belong to two genetic clusters, a zebu and a taurine cluster. While inferred sub-clusters within the taurine group corresponded extremely well to predefined breed categorizations, no real sub-clusters, corresponding to predefined breeds, existed within the zebu cluster. With the application of prior population information, cluster analysis achieved posterior probabilities from 0.962 to 0.994 of correctly assigning individuals to their rightful populations. High gene flow was evident between the zebu populations. Positive and negative implications of the observed genetic structure of the breeds on their development, improvement and conservation are discussed. The study shows that the breeds are threatened by uncontrolled breeding and therefore are at risk to become genetically uniform in the future. This situation can be avoided by putting in place effective breeding and management measures aimed at limiting uncontrolled mating between the breeds and to preserve special characteristics, genetic as well as breed biodiversity. The first step towards realizing these goals might be to geographically demarcate the breeds.

Animals↗
PubMed1987

[Changes in the iron content, erythrocytes and hemoglobin in the blood of poultry with acute experimental fowl typhoid].

The dynamic was followed up of the concentration of iron in the blood serum and the liver, of the erythrocyte count, of the haematocrit value of blood, and of the haemoglobin level in chickens of the New Hampshire breed at the age of 300 days, with experimentally induced acute typhoid. It was found that blood serum iron dropped abruptly as early as the second day of infection, whereas the level of iron in the liver rose. The erythrocyte count dropped almost twice as early as the second day following infection, the haematocrit value of the blood following the fluctuations of the erythrocyte count. The haemoglobin level dropped considerably on the third day, with gradually lowering values up to the seventh day. All changes that were recorded with these indices of the blood were found to precede the onset of the first clinical signs of the disease. The values of the haematologic indices with birds that survived came back to normal after the fourteenth day of infection. In the author's personal view leading in the pathogenesis of acute typhoid with the New Hampshire chickens was the lowered amount of serum iron, which disturbed the synthesis of haemoglobin and hence the maturity of erythrocytes, substantiating their lower count. The trophism of vitally important organs and tissues was also found to be disturbed.

Acute Disease↗
PubMed1995

Endocrine basis of the reproductive pattern of the Gentoo penguin (Pygoscelis papua): winter breeding and extended laying period in northern populations.

Changes in plasma LH, prolactin, testosterone, estradiol, and progesterone were investigated throughout moult and reproduction in free-living male and female Gentoo penguins (Pygoscelis papua) at Crozet Island (46 degrees S, 51 degrees E), where this species is able to relay after a reproductive failure. In both sexes, LH, prolactin, and steroid hormones, remained at basal levels during the moult. LH level was highest at the time of arrival at the colony for breeding and, although it decreased after courtship, it did not drop at basal value by incubation and first chick brooding period. Prolactin peaked for both chick brooding periods; replacement clutch was associated with an increased secretion of LH, whereas high prolactin levels were maintained. Testosterone, in male, and estradiol, in female, peaked during courtship I and chick brooding II; progesterone, in female, peaked during courtship I and II. These hormonal patterns are consistent with those observed in passerine species which are also able to relay after a reproductive failure. Winter breeding observed at Crozet Island might reflect the extreme adaptive capacity of Gentoo penguin species.

Adaptation, Biological↗
PubMed2025

Insights from farming Macrocystis pyrifera offshore: phenotypic analysis, genome-wide association studies, genomic selection.

Seaweed farming, as a part of aquaculture, offers a sustainable alternative to modern agricultural practices; however, genetic enhancement and breeding programs for most species are underdeveloped. We aimed to advance seaweed domestication by focusing on giant kelp (Macrocystis pyrifera), the fastest-growing haplodiplontic brown alga, which has significant ecological and commercial importance. We analyzed phenotypic data from two offshore experimental farms conducted in 2019 and 2020, which involved hundreds of outplanted genetically diverse sporophytes. We found that outplanting season and farm design had significant effects on giant kelp biomass. Broad-sense heritability estimates showed moderate (0.27-0.50) genetic contributions to two phenotypes, carbon content and total biomass. Genome-wide association studies for these phenotypes resulted in three statistically significant SNPs, located near or within genes involved in carbohydrate metabolism and cytoskeletal functions. In addition, we applied genomic selection models that integrated sporophyte phenotypes and parental gametophyte genotypes. These models utilized reduced sets of GWAS-ranked SNPs obtained by a procedure based on linkage disequilibrium estimations. Model testing yielded cross-validation accuracy values of up to 0.84 and predictive accuracy values of up to 0.40, demonstrating the potential of marker-assisted breeding for phenotype improvement. Our results provide foundational genomic resources and tools for domesticating and breeding M. pyrifera, offering a basis for developing giant kelp varieties with desirable traits.

Journal Article↗
PubMed2004

A comparison of inbreeding rates in India, Japan, Europe and China.

This is a report on an application of a new method for estimating inbreeding rates in large, semi-isolated populations over time. This study is intended to further show the versatility of the method. In a previous study, the method was shown to be useful in analysing the effect of details in a single population curve on inbreeding. In this study, the method is applied to the population curves of India, Japan, Europe and China over the past two millennia, to allow inter-comparisons of the inbreeding within those populations. Anthropologists traditionally concentrate on small isolates within a country for the estimation of inbreeding. Those isolates, however, might not be representative of the country as a whole. The method used in this study attempts to estimate inbreeding over large regions over an extended period of time. The method models the genealogical 'paradox' and yields estimates of the average inbreeding in terms of Pearl's coefficient Z, as a function of time. It is first assumed that the whole population of each country is the adult (breeding) population, corresponding to minimum inbreeding. It is found that the more complex the population curve examined, the greater the precision of the Z curves obtained. The effect of incorporating a single known value of inbreeding into the analyses is also investigated. This procedure produces a more realistic situation where the adult (breeding) population is considerably less than the entire population. It is shown, that if it is assumed that the whole population of the country is the adult (breeding) population, then a present day person from one of the four regions/countries studied is descended from between 72% and 97% of the early medieval population of the particular country. On the other hand, if a known value of inbreeding for Britain is incorporated into the analysis, these values become of the order of 1% for the older-settled regions/countries, and about 16% for Japan. However, that value for Japan is reduced to about 1% when a known value of inbreeding for this country is used. Although some uncertainty in these results remains, the versatility of the method demonstrated here will provide more accurate results, as better input-data become available.

Adult↗
PubMed1988

Estimation of phenotypic selection differentials for predicting genetic responses to ratio-based selection.

Ratios of the phenotypic values of two traits may be used as selection criteria in animal and plant breeding to improve the ratio traits themselves or to effect changes in their two component (numerator and denominator) traits. Prediction of genetic responses to ratio-based selection would facilitate quantitative analysis and evaluation of selection based on ratios. Methods for predicting such responses are derived and presented here. They employ expressions for the truncation value of a ratio and for the phenotypic selection differentials of the numerator and denominator traits. The derivation of these expressions is based upon the assumption that the phenotypic values of each of these traits are normally distributed. Worked examples relating to livestock and crop improvement are included to demonstrate how responses to selection for ratios may be predicted.

Agriculture↗
PubMed1996

Heritability estimate of hypertrophic cardiomyopathy in pigs (Sus scrofa domestica).

The purpose of this study was to evaluate the heritability of hypertrophic cardiomyopathy (HCM) in pigs and the relation between HCM and heart measurements, pathologic features, and growth to provide references for HCM line development. A total of 353 on-farm tested gilts (females) and boars (males) from 74 sire families were randomly selected from a single breeding farm where HCM was prevalent. Hearts were collected after animals were slaughtered. Heart length, width, and weight, heart-to-body weight ratio, and thickness of the cranial, middle, and caudal portions of the ventricular septum, left and right ventricles, and apex were measured. Cardiac hypertrophy and myocyte disorganization, myocardial and endocardial fibrosis, and intramural coronary arterial occlusion were used as criteria for HCM. Growth traits were evaluated from average daily body weight gain, ultrasonically determined backfat thickness, loin-eye area, and performance selection index. Heritability of the disease was estimated by treating it as a threshold trait. The prevalence of HCM in three studied breeds was 5.26 in Duroc, 22.98 in Landrace, and 5.56% in Yorkshire pigs. The value in Landrace pigs was significantly (P < 0.001) higher than that in the other pigs. There was no significant difference between sexes. In general the heart of pigs with HCM was heavier, wider, longer, and thicker than that of clinically normal pigs. Backfat was the only growth trait with a difference (P < 0.05) among pig breeds. The HCM pigs were leaner than normal pigs. Leaner pigs may have a higher risk of HCM. Heritability of HCM was > 0.30 for all three breeds, but the standard errors of these estimates were high because of limited sample size, in particular for the Yorkshire and Duroc breeds. The preliminary results of this study indicate that HCM in pigs is moderately heritable; thus development of a high-HCM incidence line by selection is possible.

Animals↗
PubMed2002

The influence of age and gender on haematological parameters in Lipizzan horses.

Haematological parameters [red blood cell count (RBC), white blood cell count (WBC), packed cell volume (PCV), haemoglobin concentration, mean cell volume (MCV), mean cell haemoglobin (MCH) and mean cell haemoglobin concentration (MCHC)] in resting Lipizzan horses were determined for 143 stallions, 104 mares and 25 foals. The mean RBC and WBC values in Lipizzans were in the lower part of the normal range for warm-blooded horses. The mean PCV, MCV and MCH values were higher, but the mean haemoglobin concentration and MCHC values were lower than reported for other warm-blooded horses. In foals, the mean RBC, WBC, PCV, haemoglobin concentration and MCHC values were higher, whereas MCV and MCH were lower than in older animals. Results indicating a significant decrease in WBC (P < 0.01) and an increase in MCV, MCH and MCHC (P < 0.05) with increasing age are consistent with some other reports on warm-blooded horses. The age-related variations in RBC and PCV were less marked. Contrary to some reports, RBC (P < 0.01), WBC and haemoglobin concentration (P < 0.001) were higher in Lipizzan stallions than in mares, but differences in MCHC, MCH and MCV were insignificant. The specific haematological values determined in Lipizzans are presumably a result of selection and should be taken into consideration when dealing with this race of horses.

Age Factors↗
PubMed1988

Fasting in king penguin. I. Hormonal and metabolic changes during breeding.

During long-term fasting in birds and mammals, protein utilization initially decreases (phase I), is thereafter maintained at a low value (phase II), and then further increases (phase III). To delineate hormonal and biochemical changes responsible for these modifications, the effect of food deprivation for 50 days was studied in 6 male king penguins captured at the beginning of their natural breeding fast. During phase II, both rate of mass loss and plasma uric acid concentration remained at low levels, whereas plasma beta-hydroxybutyrate concentration increased. In phase III there was by contrast a 2.5-fold increase in the rate of mass loss, an eightfold increase in plasma uric acid, and an 80% drop in plasma beta-hydroxybutyrate. Plasma corticosterone was low and steady in phase II and increased three times in phase III. During the overall fast, there were no significant variations in plasma insulin, but there was a fourfold increase in plasma glucagon and a decrease in plasma thyroxine and triiodothyronine. These findings suggest that protein sparing (phase II) requires low levels of corticosterone, insulin, and thyroid hormones, whereas the further increase in protein utilization (phase III) is due to an increase in plasma corticosterone. The high plasma glucagon concentration in phase III is presumably responsible for a transient increase in plasma glucose observed at this stage; such increase in glucagon could enhance gluconeogenesis from amino acids.

Aldosterone↗
PubMed2026

Mul-PheG2P: decoupled learning and prediction-space fusion enables robust and interpretable multi-phenotype genomic prediction.

Genomic prediction of multiple phenotypes is crucial in modern plant breeding; however, existing methods struggle with negative transfer and lack interpretability, particularly across high-dimensional small-sample data and diverse species. To address this, we propose Mul-PheG2P, a novel paradigm based on decoupled learning and predictive space fusion. It employs a two-stage design: first training phenotype-specific encoders using genetic data, then decoupling phenotype-specific learning from cross-phenotype aggregation via an interpretable prediction layer. Mul-PheG2P outperforms existing methods across diverse crop datasets, including maize (Zea mays), wheat (Triticum aestivum), and tomato (Solanum lycopersicum). It provides a multi-scale interpretability chain: at the macro level, it quantifies phenotypic contributions via attention-based weighting; at the micro level, Integrated Gradients reveal the genetic basis of predictions. Notably, the model successfully identified the CCT (CONSTANS, CO-like, and TOC) motif regulating photoperiodism and the SQUAMOSA (SQUAMOSA promoter binding protein) promoter for inflorescence development, confirming its ability to capture functional biological mechanisms. These results highlight the high performance and interpretability of Mul-PheG2P, showcasing its value for low-cost, large-scale screening to advance precision breeding.

Phenotype↗
PubMed1976

[Frequency and differentiation of defective spermatozoa in relation to various clinical testicular changes in black-pied Holstein bulls].

An occurrence of pathological spermatozoa and their differentiation in relation to the clinical state of the testes in the Holstein bulls was studied under the subtropical conditions of Cuba. In animals without clinical testicular findings an average count of pathological spermatozoa was relatively high (16.4%), it increased in breeding bulls suffering from testicular degeneration (22.72%), and it reached the maximum values in bulls with testicular fibrosis (29.52%). Primary defects were mostly found on heads, fewest changes were observed on the neck of spermatozoa. A finding of the set of acrosomal defects was prevalent on the spermatozoon head; the defects were heaviest in bulls with testicular fibrosis. In those animals, a higher frequency of piriform spermatozoon heads was found out. A high incidence of protoplasmic drops was observed as well;it was highest in fibrotic bulls (8.27%). In dependence on the clinical state of gonads, the testis produces an increasing amount of pathological spermatozoa. That is to say the proportionate representation of various defects is similar to each other when given biological excrements at different states of gonads are considered.

Animals↗
PubMed2006

Rapidly advancing laying date in a seabird and the changing advantage of early reproduction.

1. Bird ringing schemes have collected immense amounts of data on timing of breeding for over 100 years. These data provide an unexploited source of information on temporal change in breeding date. 2. We investigated changes in breeding date of the Arctic tern Sterna paradisaea Pont. in Denmark during 1929-98, using information on ringing date of young. 3. Mean ringing date advanced by over 18 days during 70 years, while there was no temporal change in variance in date. 4. Advanced mean ringing date was explained by an increase in mean temperature during April and May and an increase in North Atlantic Oscillation (NAO) index for May. 5. Variance in ringing date increased in years with high temperatures in April and high NAO index values in April. 6. There was changing temporal patterns of selection for early breeding as reflected by analyses of the difference in mean ringing date for Arctic tern young that were subsequently recorded as survivors and mean ringing date for all young. The intensity of selection on breeding date changed from favouring late breeding in the 1930s to favouring early breeding during the 1990s. 7. Analyses of bird ringing information for millions of offspring of hundreds of bird species deposited in national ringing schemes may provide unlimited access to long-term time series of reproductive variables.

Animals↗
PubMed2005

Seasonal thyroidal activity and reproductive characteristics of Iranian fat-tailed rams.

An experiment was conducted to study seasonal variations of thyroidal activity, serum testosterone concentration and seminal characteristics of two breeds of Iranian fat-tailed sheep. Eight 3 to 4-year-old rams of Ghezel and Mehraban breeds (4 rams/breed) were randomly selected from a flock of fertile rams. Semen was collected by using an artificial vagina, and blood samples were obtained via jugular vein. Seminal characteristics, scrotal length, width, and circumference, and blood parameters were measured at 3-week intervals. Time of the year significantly (P < 0.05) affected the volume of semen, sperm concentration, percent live sperm, percent normal sperm, total sperm number, seminal pH, seminal lactate dehydrogenase (LDH) concentration, scrotal circumference, scrotal width, and serum levels of testosterone, cholesterol, triiodothyronine (T(3)), tetraiodothyronine (T(4)), free T(4) index (FT(4)I), and TSH. Scrotal length was not affected by the time of sampling (P > 0.05). The effect of breed on the serum concentrations of hormones and cholesterol was not significant. Volume of semen, percent normal sperm, and total number of normal sperm were significantly (P < 0.05) higher in Mehraban but scrotal circumference, scrotal width and scrotal length were greater in Ghezel rams. Breedxtime interaction effect was significant for T(4), FT(4)I, sperm concentration, and total sperm number. The largest values for TSH, T(4), FT(4)I, testosterone, total sperm number, percent normal sperm, percent live sperm, sperm concentration, volume of semen and scrotal circumference were found from early summer to winter and the lowest values were recorded at the end of spring and in early summer. In both breeds, high and negative correlations (r = -0.7 to -0.8) were found between LDH levels in semen and percent live sperm, percent normal sperm and total sperm number (P < 0.01). It is unlikely that such variations in seminal quality would affect the fertility under natural mating.

Animals↗