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[Myocardial fibrosis of cattle in Hesse].

Between 1986 and 1989 there were 9 cases of idiopathic congestive heart failure at this clinic. Normally heifers in the last 1/3 of pregnancy and young cows aged between 2.5 and 3.5 years were affected, but the disease also occurred in one younger (1.5 years), one older (6 years) and in one male animal. In contrast to other reports, myocardial fibrosis in the State of Hesse was only seen in the Rotbunte breed. The animals suffered from a severe heart failure with venous congestion and congestive edema of the brisket, the submandibular area and the ventral abdomen. In most cases there is no precise difference in history, clinical findings and laboratory findings between myocardial fibrosis, traumatic pericarditis and endocarditis valvularis. Only pathological and histological examinations of the heart confirm a suspected myocardial fibrosis: The heart is enlarged and dilatated and seems to be non-elastic. Microscopically a scattered interstitial fibrosis and signs of myocardial degeneration are visible.

Animals↗

Leaf Rust in Rye: From Pathogen Biology to Host Defense and Resistance Breeding.

Leaf rust (LR), caused by Puccinia recondita f. sp. secalis (Prs), is considered one of the most dangerous rye (Secale cereale L.) diseases, causing yield losses exceeding 35%. This review summarizes all currently available data about this disease: pathogen characteristics (including its life cycle, natural variation, and disease symptoms), resistance resources, and the background of the plant immune response at the genome, transcriptome, and metabolome levels. The research conducted so far has allowed for the identification of dozens of genes that play a significant role in the rye immune response to Prs infection. Among them, genes encoding NBS-LRR proteins (including SECCE1Rv1G0014220, the most likely Pr3 candidate), glycosyltransferase, β-1,3-glucanase, 1-deoxy-D-xylulose 5-phosphate synthase, β-1,3-glucanase, UDP-glycosyltransferase, pathogenesis-related protein 1, ammonium transporter, and cytochrome P450 enzymes are candidates for seedling and all-stage resistance, whereas ScLr_ABC25 currently represents the most promising candidate associated with adult-plant resistance. Among the metabolites differentially accumulated in response to Prs, those related to phenylpropanoids, diterpenoids, and thiamine branches seem to play the most important role in the immune response. Finally, we suggest how the knowledge acquired so far about the rye-Prs interaction can be used in modern breeding programs aimed at obtaining cultivars with enhanced resistance to LR, such as through the use of functional gene markers and/or metabolic biomarker-assisted selection and, in the more distant future, by developing and applying new genomic techniques for precise editing of resistance and susceptibility genes, engineering synthetic immune receptors and decoys, and pan-genomic exploration for identification of rare or lineage-specific resistance alleles. [Formula: see text] Copyright © 2026 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Plant Diseases↗

Geometric analysis of the proximal femur in a diverse sample of dogs.

Dogs are often used as experimental models for studies of human hip replacement. A precise knowledge of femoral morphology is required to improve osteointegration of cementless prostheses by bone ingrowth or determination of the best design for total hip prostheses. To better understand the differences between breeds, we measured or calculated 24 external and internal features of the femur on standard radiographs of dogs that differed greatly in size and body type. We considered the appropriateness of the canine model for human total hip replacement studies and show that human and canine femurs differ in characteristics like anteversion, cortico-medullary index or endosteal shape. Knowledge of these differences and similarities makes it possible to design well-adapted stems for dogs.

Animals↗

Heterosis, marker mutational processes and population inbreeding history.

Genotype-fitness correlations (GFC) have previously been studied using allozyme markers and have often focused on short-term processes such as recent inbreeding. Thus, models of GFC usually neglect marker mutation and only use heterozygosity as a genotypic index. Recently, GFC have also been reported (i) with DNA markers such as microsatellites, characterized by high mutation rates and specific mutational processes and (ii) using new individual genotypic indices assumed to be more precise than heterozygosity. The aim of this article is to evaluate the theoretical impact of marker mutation on GFC. We model GFC due to short-term processes generated by the current breeding system (partial selfing) and to long-term processes generated by past population history (hybridization). Various mutation rates and mutation models corresponding to different kinds of molecular markers are considered. Heterozygosity is compared to other genotypic indices designed for specific marker types. Highly mutable markers (such as microsatellites) are particularly suitable for the detection of GFC that evolve in relation to short-term processes, whereas GFC due to long-term processes are best observed with intermediate mutation rates. Irrespective of the marker type and population scenario, heterozygosity usually provides higher correlations than other genotypic indices under most biologically plausible conditions.

Alleles↗

Comparison of two thiopental infusion rates for the induction of anaesthesia in dogs.

OBJECTIVE: To compare the induction dose requirements of thiopental using two different infusion rates for induction of anaesthesia in dogs. STUDY DESIGN: Prospective, randomized study. ANIMALS: Fifty, healthy (ASA I or II) client-owned dogs with a mean age of 4.1 years and a mean mass of 20.4 kg undergoing elective surgery. MATERIALS AND METHODS: Animals were randomly assigned to receive an infusion of 2.5% thiopental at a rate of either 0.1 ml kg(-1) minute(-1) or 0.4 ml kg(-1)minute(-1), 30-40 minutes after pre-anaesthetic medication with intramuscular acepromazine (0.025 mg kg(-1)) and pethidine (3.5 mg kg(-1)). Thiopental administration was controlled by a precision syringe driver. Statistical analyses of the results, using the outcome 'mg kg(-1) required for induction' (log-transformed) included unpaired t-tests for all categorical data (thiopental infusion rate, breed, sex, obesity, sedation quality) and univariable linear regression for continuous variables (mass, age). All variables were then considered in a multivariable linear regression model. The quality of induction with the two different infusion rates was also assessed. RESULTS: After controlling for quality of sedation, the thiopental induction dose requirement was significantly less (p < 0.001) with the slower infusion rate (median = 7.5 mg kg(-1); range 4.9-13.7) compared with the faster infusion rate (median =11.0 mg kg(-1); range 6.6-18.0). The quality of sedation also affected the dose required (p = 0.03). The slower infusion rate was associated with a significantly poorer induction quality (p = 0.03) [corrected] CONCLUSIONS: Slow thiopental infusion (0.1 ml kg(-1) minute(-1)) for anaesthesia induction after acepromazine/pethidine pre-anaesthetic medication reduced the induction dose requirement, although the quality of induction was inferior. CLINICAL RELEVANCE: The induction dose of thiopental was reduced with a slower administration rate and so slow administration is recommended in thiopental-sensitive animals.

Anesthesia↗

Development of a progestin-based estrus synchronization program: II. Reproductive response of cows fed melengestrol acetate for 14 days with injections of progesterone and prostaglandin F2alpha.

We tested the efficacy of an estrus control system designed to provide optimal control of follicular development. In Exp. 1, postpartum cows (n = 133) and yearling heifers (n = 57) were fed either .5 mg x female(-1) x d(-1) of melengestrol acetate (MGA) or the carrier for MGA from d -13 to d 0 (d 0 = last day of MGA feeding). All females received 25 mg of PGF2alpha (i.m.) on d -13 and 0. On d -6, cows and heifers fed MGA were administered an i.m. injection of progesterone (200 mg; MGA/P4), and those fed the corn carrier (2XPGF2alpha) received no progesterone. Beginning on d 1, females were bred by AI from d 1 to at least d 5. During the estrus synchronization period (d 1 to d 5), more (P < .05) postpartum cows were observed in estrus (70.1 vs 42.4%), the timing of estrus was more (P < .05) precise, conception rate was similar, and pregnancy rate was higher (P < .05) in the MGA/P4 than in the 2XPGF2alpha treatment. More (P < .05) cows that were anestrous at the beginning of the breeding season were in estrus during the synchronization period in the MGA/P4 (55.8%) than in the 2XPGF2alpha (28.6%) treatment. In heifers, estrus was synchronized in over 90% of females, and neither conception nor pregnancy rate during the synchronization period differed between treatments. In Exp. 2, postpartum cows (n = 122) and heifers (n = 84) received treatments (MGA/P4 or 2XPGF2alpha) as described for Exp. 1 with one exception. In the MGA/ P4 treatment, progesterone was administered on d -7 rather than d -6. Females were bred by AI from d 1 to 5. The estrus response and conception rate during the synchronization period did not differ between treatments for either cows or heifers. We conclude that the progestin-based estrous synchronization system used in this study effectively synchronized an estrus of normal fertility in cyclic cows and induced a majority of anestrous cows to reinitiate estrous cycles.

Administration, Oral↗

Sensitivity patterns to house dust mites and forage mites in atopic dogs: 150 cases.

This study investigated intradermal test reactions to extracts of six species of mites in 150 dogs with atopic dermatitis. At least one positive reaction was seen in 120 animals (80%). Dermatophagoides farinae attracted the highest number of positive reactions (108 dogs, 90% of dogs and 72% of atopic dogs showing positive reactions). Positive reactions to other mites were not uncommon, with many dogs testing positive for Dermatophagoides pteronyssinus (32% of dogs tested), Acarus siro (35%), Tyrophagus putrescentiae (30%), Glycyphagus domesticus (27%) and Lepidoglyphus destructor (23%). Sensitivity to D. farinae alone occurred commonly (57% of cases), but multiple sensitivities were seen frequently with the other mites. Cases of sensitivity to only one mite were also seen: D. pteronyssinus (five cases), T. putrescentiae (one case) and G. domesticus (one case). Further studies are needed to appreciate more clearly the precise role played by the different species of mite in canine atopic dermatitis.

Allergens↗

Ph1 gene derived from Aegilops speltoides induces homoeologous chromosome pairing in wide crosses of Triticum aestivum.

The present study was conducted to investigate the effectiveness of the PhI gene transferred from Aegilops speltoides into bread wheat cultivar Chinese Spring (CS) in inducing homoeologous chromosome pairing in interspecific crosses using the Chinese Spring line, CS(PhI), carrying the gene. Chinese Spring, as well as CS(PhI), were crossed as female parents with three accessions of Ae. kotschyi (UUSS), one accession of Secale cereale (RR), two amphiploids of Triticum durum-Ae. caudata (AABBCC), and one amphiploid of Triticum durum-Ae. umbellulata (AABBUU). Meiotic metaphase I chromosome pairing was studied in all the interspecific crosses with CS as well as CS(PhI). There was significant increase in chiasma frequency in all the crosses with CS(PhI) over those with CS. The extent of induced homoeologous chromosome pairing by PhI in crosses of CS(PhI) with S. cereale was higher than with those of Ae. kotschyi, as indicated by higher chiasma frequency per pollen mother cell. Significant reduction in frequency of univalents and increase in bivalents (>14), multivalents, and chiasma frequency in crosses of amphiploids with CS(PhI) as compared to those of CS indicated induced homoeologous pairing between C and D, D and U, and C, D, and U genomes with AB genomes in the presence of PhI. The results of the present study unequivocally demonstrate the effectiveness of PhI gene transferred from Ae. speltoides in hexaploid wheat in inducing homoeologous chromosome pairing and suggest that the line CS(PhI) can be effectively used for precise transfer of useful alien genetic variations with least linkage drag.

Alleles↗

The high grain protein content gene Gpc-B1 accelerates senescence and has pleiotropic effects on protein content in wheat.

High grain protein content (GPC) is a frequent target of wheat breeding programmes because of its positive effect on bread and pasta quality. A wild wheat allele at the Gpc-B1 locus with a significant impact on this trait was identified previously. The precise mapping of several senescence-related traits in a set of tetraploid recombinant substitution lines (RSLs) segregating for Gpc-B1 is reported here. Flag leaf chlorophyll degradation, change in peduncle colour, and spike water content were completely linked to the Gpc-B1 locus and to the differences in GPC within a 0.3 cM interval corresponding to a physical distance of only 250 kb. The effect of Gpc-B1 was also examined in different environments and genetic backgrounds using a set of tetraploid and hexaploid pairs of isogenic lines. The results were consistent with those observed in the RSLs. The high GPC allele conferred a shorter duration of grain fill due to earlier flag leaf senescence and increased GPC in all four genetic backgrounds. The effect on grain size was more variable, depending on the genotype-environment combinations. These results are consistent with a model in which the wild-type allele of Gpc-B1 accelerates senescence in flag leaves producing pleiotropic effects on nitrogen remobilization, total GPC, and grain size.

Alleles↗

Evaluation of an ultrasonic amplitude depth analysis technique for pregnancy diagnosis in the cow.

Beef and dairy cows (n = 1,053) were tested for pregnancy on 7 farms by ultrasonic scanning. Accuracy was verified by comparison with rectal palpation. Rectal palpation was done 40 to 75 days after breeding and was considered 100% accurate for comparison purposes. Although diagnostic accuracy of the ultrasonic scanning technique was less than 100%, a confidence interval no larger than 2.3% indicated a high degree of precision for pregnant cows. The confidence interval in the nonpregnant category ranged from 9.2% to 11.8%, which was small in relation to the variation in ultrasonic scanning accuracy. However, considering the large number of cows and the experimental bias that was purposely introduced, the lower accuracy of the ultrasonic method was not unexpected. Cystic ovaries, partially involuted uteri, metritis, and high milk production prevalent at one location accounted for much of the variation observed and lowered the overall accuracy for all cows tested. The ultrasonic analyzer has potential in testing cows for pregnancy; however, technical improvements in machine configuration must be made and additional testing in controlled experiments and field trials must be conducted before an accurate analysis of this method can be made. At the present state of development, ultrasonic amplitude depth analysis cannot replace rectal palpation for diagnosis of pregnancy in cattle.

Animals↗

Pigeonpea (Cajanus cajan L. Millsp.).

Pigeonpea [Cajanus cajan (L.) Millsp.], also known as redgram, is one of the major grain legume (pulses) crops grown in the semiarid tropics (SAT) extending between 30 degrees N and 30 degrees S; it is the second most important food legume of India. It is cultivated in about 50 countries of Asia, Africa, and the Americas for a variety of uses (food, fodder, fuel wood, rearing lac insects, hedges, wind breaks, soil conservation, green manure, roofing, and so on). The constraints of enhancing its productivity include the damage caused by various fungi, bacteria, viruses, and insect pests. Conventional plant breeding methods have not been successful for the improvement of pigeonpea because of genetic variation and incompatibility among the wild varieties. Genetic engineering technology can therefore be used as an additional tool for the introduction of agronomically useful traits into established varieties. The development of plant transformation techniques has been a major breakthrough in overcoming constraints to achieve precision in genetic manipulation. The development of efficient plant regeneration protocols is a prerequisite for recombinant technology to carry out genetic transformation. This chapter describes an Agrobacterium-mediated transformation protocol for pigeonpea, a simple, efficient, and reproducible method that is applicable across diverse genotypes of pigeonpea.

Agrobacterium tumefaciens↗

Spore number control and breeding in Saccharomyces cerevisiae: a key role for a self-organizing system.

Spindle pole bodies (SPBs) provide a structural basis for genome inheritance and spore formation during meiosis in yeast. Upon carbon source limitation during sporulation, the number of haploid spores formed per cell is reduced. We show that precise spore number control (SNC) fulfills two functions. SNC maximizes the production of spores (1-4) that are formed by a single cell. This is regulated by the concentration of three structural meiotic SPB components, which is dependent on available amounts of carbon source. Using experiments and computer simulation, we show that the molecular mechanism relies on a self-organizing system, which is able to generate particular patterns (different numbers of spores) in dependency on one single stimulus (gradually increasing amounts of SPB constituents). We also show that SNC enhances intratetrad mating, whereby maximal amounts of germinated spores are able to return to a diploid lifestyle without intermediary mitotic division. This is beneficial for the immediate fitness of the population of postmeiotic cells.

Carbon↗

[Applicability of methods for determining air velocity in livestock buildings].

Comparative studies were carried out on the applicability of the katathermometers, mechanical anemometers, and the thermoelectric anemometer type TEA-4, devised by the authors and introduced into practice, for determining the velocity of air in livestock buildings. TEA-4 proved more perspective for measurements in animal breedings as it makes possible a continuous automatic control on air velocity. This, in turn, renders it feasible to follow up the day-and-night and the seasonal dynamics of this microclimate factors. By preciseness and exploitation dependability TEA-4 has proved superior to katathermometers and mechanical anemometers. Its adoption into practice has made it possible to shorten the time of measurement.

Animals↗

Advances in Cytoplasmic Male Sterility in Sugar Beet from Mitochondrial Genome Structural Dynamics and Nuclear-Cytoplasmic Coordination.

Sugar beet (Beta vulgaris L.) is a globally important sugar crop whose hybrid breeding system relies heavily on cytoplasmic male sterility (CMS) lines. Recent advances in sugar beet genomics, particularly the release of high-quality reference genomes and the characterization of organellar genomes, have provided a foundation for elucidating the molecular genetic mechanisms of CMS. Furthermore, innovations in gene editing technologies are enabling transformative functional studies in this field. The precise targeting of CMS-associated mitochondrial genes and nuclear restorer-of-fertility genes not only allows for direct investigation of theoretical models governing fertility regulation through nuclear-cytoplasmic interactions but also holds promise for the targeted development of sterile and restorer lines. This review systematically summarizes progresses in sugar beet genomics, the development of gene editing tools, and the current understanding of the molecular genetics of CMS and fertility restoration in sugar beet. Although challenges remain-such as efficient delivery of editing tools into mitochondria and coordinated editing of multiple genes-the integration of genomic and gene editing technologies is expected to accelerate multi-omics-guided dissection of CMS mechanisms. These advances will facilitate the precise design of high-yield, high-sugar, and stress-resistant sugar beet hybrids, thereby providing core scientific and technological support for the sustainable development of the global sugar industry.

Beta vulgaris↗

Coyote laparotomy: in vivo determination of reproductive success.

Reproductive tracts of 24 female coyotes hand-reared for behavioral research were examined by laparotomy following the 1977-78 breeding season. Litter counts revealed 51 whelps with 10 of the 24 females while examination by laparotomy indicated 83 uterine swellings in 18 of the same 24 females. The laparotomy proved to be an effective, relatively precise procedure and gave a 39% increase in data acquisition.

Journal Article↗

[Topographic and histological study of the sinoatrial node in the Jaffarabadi buffalo (Babalus bubalis Linnaeus, 1758)].

A topographic and histologic study of the sinuatrial node was made in the hearts of 12 buffalo of the Jaffarabadi breed, 8 adults (5 females and 3 males) and 4 term fetuses (3 female and 1 male). The nodal tissue was localized at the junction of the vena cava superior with the right atrium, occupying, more precisely, the entire extent of the terminal groove, the dihedral cavoatrial angle and the first part of the auricular surface of the junction, which is contiguous with this angle. This structure contains cells with single or double nuclei, round or oval in shape, surrounded by a light halo, with scattered chromatin and a well-defined nucleolus, acidophilic cytoplasm containing, in comparison with the common myocardium, few sinuous myofibrils with transverse striations and a larger amount of glycogen. We also observed arteries of small and medium caliber, with veins and nerves accompanying the nodal mass, while the nerve ganglia were situated opposite the sinuatrial node.

Animals↗

Multiplexed microsatellite markers for the genetic analysis of Eucalyptus leucoxylon (Myrtaceae) and their utility for ecological and breeding studies in other eucalyptus species.

Eucalyptus leucoxylon is a widespread woodland tree species found in southeastern Australia that has suffered from, and continues to be, threatened by the impacts of habitat clearance and degradation. Populations now consist predominantly of scattered individuals, and their conservation status is of increasing concern. We report the development and characterization of a set of eight highly polymorphic microsatellite loci for E. leucoxylon. The loci can be amplified in three PCR multiplexes and electrophoresed in a single lane, allowing rapid throughput of large numbers of samples. A total of 111 alleles were detected in 68 individuals with an average of 12.3 alleles per locus, a mean expected heterozygosity of 0.83, and a mean observed heterozygosity of 0.72. The combined probabilities of identity and probabilities of paternity exclusion allow an extremely precise level of individual identification, indicating that these microsatellite markers will be ideal for population genetic and parentage-type studies in E. leucoxylon. The markers also exhibited an average of 76% conservation within the subgenus Symphyomyrtus, to which E. leucoxylon belongs, and 53% conservation across other subgenera of Eucalyptus, demonstrating the potential of these markers in ecological and breeding studies in a wide range of Eucalyptus species.

Australia↗

Efficacy of methods used to test fertility of beef bulls used for multiple-sire breeding under range conditions.

A study was conducted during the 1982, 1983 and 1984 breeding seasons with 277 crossbred bulls, 1 to 3 yr of age, that were evaluated for physical soundness, testicular development, seminal quality, and both sexual and social behavior immediately before exposure to crossbred cow herds ranging in size from 89 to 329 cows. Crossbred cow herds were exposed to 4 to 24 bulls per breeding group (mean of 14) at a mean female: male ratio of 21.2 +/- .6:1 under extensive range conditions for 31 to 62 d (mean 46.6 d). All resulting calves were blood-typed to determine the number of calves sired by each bull as an estimate of his fertility. The mean number of calves sired by 1- (n = 116), 2- (n = 126) and 3-yr-old (n = 35) bulls was 4.7 +/- .1, 8.2 +/- .1 and 10.5 +/- .1, respectively. A regression model for predicting bull fertility under multiple-sire, range breeding conditions was selected that accounted for 29% of the total variance in fertility. Similar models accounted for a greater proportion of variance in fertility of 1-yr-old (37%) than of 2-yr-old bulls (22%). Due to the large amount of unexplained variation, the model could not predict individual bull fertility precisely. However, this study demonstrated that selection of herd sires with large scrotal circumference, low backfat thickness, low levels of primary sperm defects, and a low number of mounts in combination with a moderate number of services during libido testing would be expected to improve fertility of beef bulls used under extensive range conditions.

Adipose Tissue↗