Multicystic degeneration of the Cowper's gland in a Large White boar

Artificial insemination and optimization of the use of seminal doses in swine

The optimization of processes associated with artificial insemination (AI) is of great importance for the success of the pig industry. Over the last two decades, great reproductive performance has been achieved, making further significant progress limited. Optimizing the AI program, however, is essential to the pig industry's sustainability. Thus, the aim is not only to reduce the number of sperm cells used per estrous sow but also to improve some practical management in sow farms and boar studs to transform the high reproductive performance to a more efficient program. As productivity is mainly influenced by the number of inseminated sows, guaranteeing a constant breeding group and with healthy animals is paramount. In the AI studs, all management must ensure conditions to the health of the boars. Some strategies have been proposed and discussed to achieve these targets. A constant flow of high-quality and well-managed breeding groups, quality control of semen doses produced, more reliable technology in the laboratory routine, removal of less fertile boars, the use of intrauterine AI, the use of a single AI with control of estrus and ovulation (fixed-time AI), estrus detection based on artificial intelligence technologies, and optimization regarding the use of semen doses from high genetic-indexed boars are some strategies in which improvement is sought. In addition to these new approaches, we must revisit the processes used in boar studs, semen delivery network, and sow farm management for a more efficient AI program. This review discusses the challenges and opportunities in adopting some technologies to achieve satisfactory reproductive performance and efficiency.

MRI Anatomical Investigation of Rabbit Bulbourethral Glands

Anatomical MRI is appropriate for the interpretation of soft tissue findings in the retroperitoneal part of the pelvic cavity. The aim of the current study was to use rabbits as an imaging model to optimize MRI protocols for the investigation of bulbourethral glands. The research was conducted on twelve clinically healthy, sexually mature male rabbits, eight months of age (New Zealand White), weighing 2.8 kg to 3.2 kg. Tunnel MRI equipment was used. The transverse MRI in the T2-weighted sequence obtained detailed images that were of higher anatomical contrast than those in T1-weighted sequences. The hyperintensity of the glandular findings at T2, compared to the adjacent soft tissues, was due to the content of secretory fluids. The quality of the anatomical tissue contrast has not shown much dependence on the choice of the sequence in dorsal MRI. The sagittal visualization of the rabbit bulbourethral glands corresponded to the localization of the research plane toward a median plane. The imaging results could be used as a morphological base for clinical practice and reproduction.

Effect of housing conditions, management procedures and traits of the external male reproductive tract on the sexual behaviour of natural mating boars

Although artificial insemination in pig production is widespread, many farms rely on natural mating (NM). For NM to be successful, adequate sexual behaviour and a sufficient libido level in boars is crucial for appropriate reproductive performance. Therefore, this observational study evaluated the libido level of 59 boars of different breeds used for NM by a scoring system ranging from 0 (no libido) to a maximum of 23 points (perfect libido) and analysed their general and andrological health as well as housing and management factors influencing the libido. The boars showed a mean libido score of 16.7 (SD ± 2.3). Crossbreed (median: 17.5, min: 14.0, max: 21.0) (p < 0.01) and Landrace (median: 17.5, min: 17.0, max: 21.0) (p < 0.05) boars showed significantly higher libido scores compared to Piétrain boars (median: 14.0, min: 13.0, max: 17.0). A non-slippery mating area was found to be positively associated with libido (p < 0.05), whereas disorders such as lameness showed a negative correlation (p < 0.01). In winter, significantly higher libido values (median: 17.0, min: 14.0, max: 21.0) were recorded compared to spring (median: 16.0, min: 11.0, max: 21.0) (p < 0.05). In addition, high number of supports by farmers during natural mating and frequency of use for NM and for stimulation of artificially inseminated sows did not negatively influence the libido score. No significant correlation between the satisfaction of the farmer about the libido level of the boars and the evaluated libido score was detected. This is the first study investigating the effect of housing conditions and management procedures on the libido of boars used for NM under field conditions. The findings may therefore help to establish a successful mating management for herds applying NM on a regular basis. A systematic evaluation of the libido score is needed to detected boars with low libido levels, because it is often overlooked by the farmers. Moreover, genetics, general health condition and flooring in mating areas turned out to be critical parameters that influence the libido score of boars used for NM and therefore should be considered when examining natural mating on farm.

Phenotypic and Genomic Analysis of Cystic Hygroma in Pigs

Cystic hygroma is a malformation of the lymphatic and vascular system and is recognized as a benign congenital tumor that affects humans and animals in the perinatal period. This congeni-tal disorder is rarely described in animals, and until today, cystic hygroma in pigs has not been described in the literature. In a purebred Piètrain litter with twelve live-born piglets, cystic hy-groma was noticed on the rump of two male pigs within the first week of life. In addition, a third case of a crossbred weaner (Large White × Landrace) was detected during a herd examina-tion. To rule out common differential diagnoses, e.g., abscess or hematoma, further clinical and pathological investigations were conducted. During clinical examination, a painless and soft mass, which was compressible, was detected on the rump of all affected animals. The ultra-sonographic examination revealed a fluid-filled and cavernous subcutaneous structure. In addi-tion, a puncture of the cyst was conducted, revealing a serosanguinous fluid with negative bacte-riological culture. In all cases, a necropsy was performed, showing that the animals had fluid-filled cysts lined by well-differentiated lymphatic endothelium. Based on the clinicopathological examination, cystic hygroma was diagnosed. Furthermore, SNP array genotyping and whole-genome sequencing was performed and provided no evidence for a chromosomal disorder. In the Piètrain family, several genome regions were homozygous in both affected piglets. None-theless, a dominant acting de novo germline variant could not be ruled out, and therefore differ-ent filtering strategies were used to find pathogenic variants. The herein presented lists of pri-vate variants after filtering against hundreds of control genomes provide no plausible candidate and no shared variants among the two sequenced cases. Therefore, further studies are needed to evaluate possible genetic etiology. In general, systematic surveillance is needed to identify ge-netic defects as early as possible and to avoid the occurrence of losses in the pig population.