Porcine Health Management最新文献

This study aimed to evaluate the application of synthetized porcine follicle-stimulating hormone (spFSH) in combination with synthetized human chorionic gonadotropin (shCG) in inducing puberty in gilts, promoting estrus and ovulation in multiparous sows, and improving reproductive performance. In gilts, treatment with 30 µg spFSH + 150 IU shCG advanced the onset of puberty to 160 ~ 175 days of age in 76.62% of gilts, with a significantly lower incidence of ovarian cysts compared to PMSG and PG600. Hormonal profiling demonstrated that the applied protocol successfully induced endocrine maturation in gilts to levels consistent with those characteristic of natural puberty. In multiparous sows, the estrus-inducing effect of 30 µg spFSH + 150 IU shCG was comparable to PMSG and PG600 (400 IU PMSG and 200 IU hCG), while the incidence of ovarian cysts was significantly lower than in the PG600 group. This treatment significantly increased total piglets born per litter and reduced the number of days each piglet requires to be raised by a sow. When 300 IU shCG was used for ovulation induction, the farrowing rate significantly increased, and the number of days each piglet requires to be raised by a sow were further reduced. Hormonal analysis revealed that this treatment achieved physiological regulation of progesterone (P₄) levels, with endocrine changes better aligned with sow reproductive physiology. This study systematically evaluated the application value of spFSH in combination with shCG at different doses in the reproductive management of gilts and sows. The optimized combination significantly improved estrus expression and farrowing rates, reduced ovarian cyst incidence, improving economic efficiency, and enhanced reproductive efficiency.

Background: Porcine reproductive and respiratory syndrome virus (PRRSV) exhibits a marked geographical clustering, with PRRSV-2 being predominantly found in North America and Asia. Its presence in Europe remains extremely limited and mainly represented by vaccine-like strains, belonging to sublineage 5.1. While the use of this vaccine is possible and applied in Northern Europe, its detection in Southern European countries has been largely anecdotal.

Results: In the present study, we report the first confirmed case of PRRSV-2 detection in Italy, identifying two independent introduction events with no clear epidemiological link. A deeper evaluation of the overall epidemiological end evolutionary patterns of MLV-derived strains was performed to elucidate the present study findings. The phylogenetic and molecular analyses revealed significant genetic variability among vaccine-derived strains, with pairwise genetic distances exceeding 8% and an estimated evolutionary rate of ~10^{- 3} substitutions/site/year, comparable to field strains. These findings suggested ongoing viral evolution and persistent circulation since the vaccine introduction. Signatures of diversifying selection, particularly in ORF5, indicated adaptation to different host populations or immune environments. Moreover, phylogeographic analysis supported multiple independent introduction events of independently evolved strains rather than a single introduction followed by local evolution.

Conclusions: Contrary to expectations, PRRSV-2 vaccine-like strains exhibited transmission dynamics comparable to field strains. Their divergence, potential for adaptation, and reversion to virulence raise concerns about their long-term epidemiological and clinical impact. Given the scarcity of PRRSV-2 field strain reports in Europe, further surveillance and sequencing efforts are crucial to assess its true prevalence, evolutionary potential, and implications for swine health.

Background: While the pivotal role of the gut microbiota in lipid metabolism has been well established, the specific contributions of bacterial strains isolated from native Chinese pig breeds to lipid metabolic regulation remain largely uninvestigated. The purpose of this research was to investigate the effects of Ningxiang pig-derived L. reuteri XY227 supplementation on growth performance, lipid metabolism, and gut microbiota in finishing pigs.

Methods: Sixteen healthy Duroc × Landrace × Yorkshire (DLY) finishing pigs, with an initial body weight of 63.36 ± 1.28 kg, were randomly assigned to two groups, each with eight replicates. The dietary treatments included a basal diet and a basal diet supplemented with 0.4% L. reuteri XY227 (1 × 10¹¹ CFU/kg of basal diet). The experiment lasted for 50 days.

Results: Supplementation with L. reuteri XY227 significantly increased the final body weight (FBW) and average daily gain (ADG) (P < 0.05). Dietary supplementation with L. reuteri XY227 significantly reduced the concentrations of C12:0, C18:1n9c, C20:2, and total monounsaturated fatty acids (MUFA) (P < 0.05) in the dorsal subcutaneous adipose tissue. In the L. reuteri XY227 group, mRNA expressions of sterol regulatory element binding protein-1c (SREBP-1 C), peroxisome proliferator-activated receptor γ (PPARγ), and acetyl CoA carboxylase (ACC) in subcutaneous adipose tissue were notably reduced (P < 0.05). The expression of fatty acid translocase (FAT/CD36) was significantly elevated (P < 0.05). L. reuteri XY227 supplementation increased Cluster of differentiation 36 (CD36) mRNA expression in the jejunum and improved jejunal and ileal the height of villi (P < 0.05). Diet supplemented with L. reuteri XY227 significantly boosted the abundance of Lactobacillus, Enterococcus, and Limosilactobacillus in the ileum mucosa and the valerate content in the colon (P < 0.05).

Conclusions: Collectively, these findings indicate that L. reuteri XY227 supplementation improves growth performance and modulates lipid metabolism, possibly achieved through improvements in intestinal morphology and alteration of the gut microbial community.

Background: An aceptable target range for stillbirths per litter varies between 5-7% of total born piglets in sows. Several major risk factors have been identified that contribute to the increased incidence of stillbirths in piglet-producing herds, including the use of uterotonic agents. Oxytocin and carbetocin are commonly administered to manage the farrowing process. Oxytocin is a short-acting, natural hormone that induces rapid uterine contractions, while carbetocin is a long-acting synthetic analog designed for prolonged stimulation. Both agents can affect stillbirth rates depending on timing of application, dosage, and the sow's physiological condition, emphasizing the need for cautious and informed use.

Case presentation: A Swiss piglet-producing herd suffered from an increased stillbirth rate of 8.7%. A herd examination was conducted to reveal the general health status of the herd. The birth process of eight sows, resulting in a total of 129 piglets, was analysed for birth management, total duration of birth, and duration of piglet expulsion. Each piglet was scored for meconium staining and vitality. In addition, material from stillborn and weak-born piglets was subjected to further examinations. The general physical examination of the sows before farrowing revealed no abnormalities. At different time points during the farrowing process, all sows routinely received an intramuscular treatment of 35 µg carbetocin once by the animal caretaker, which caused a prolonged piglet-to-piglet interval directly after application, loss of colostrum and an increased number of weak and stillborn piglets. Histological examination of heart samples from five stillborn piglets revealed no signs of myocarditis or other abnormalities. Moreover, qPCR for porcine circovirus type 2 on the heart samples was negative. Serology on pre-colostral serum samples of one litter with a mummified piglet were negative for antibodies towards porcine parvovirus. Porcine reproductive and respiratory syndrome virus was excluded by PCR examination of the serum of ten weak-born piglets. After stopping the routine treatment with carbetocin and improving the birth management, both recommended by the examination team, the level of stillbirths decreased to 4.6%.

Conclusion: Herd problems with stillbirths require a comprehensive herd investigation including monitoring the birth management and ruling out potential pathogens. In this case, the routinely administration of carbetocin during parturition led to severe undesirable side effects. A good monitoring during the farrowing process combined with appropriate measures and the omission of prophylactic carbetocin administration enhanced the birth process and thereby piglets' survival.

Background: In view of its massive financial impact related to increased preweaning mortality and poor growth performance, neonatal diarrhoea in piglets is widely regarded as one of the most common issues in modern swine production. Currently, the diarrhoea of undetermined aetiology arises as a complex diagnostic problem in several pig-rearing countries; therefore, the role of agents with not completely established clinical importance, such as non-group A rotaviruses (RVs), should be taken into consideration in a differential diagnosis procedure. The aim of this study was to report the detection of RVB acting as a potential causative agent of porcine diarrhoea.

Results: The investigation was conducted in a Polish commercial, high-performing farm with 3,300 sows weaning piglets in weekly batches. For the scope of this research, five 3-day-old dead diarrhoeic piglets were collected. All the animals originated from different litters displaying clinical signs regarded as typical of rotaviral enteritis. Prior to the NGS investigation, all the piglets sampled in our current investigation were tested negative for diarrhoea-associated viruses (RVA, RVC, TGEV, PEDV) using commercially available PCR setups. The NGS data for the faecal sample resulted in 510,843 reads after adapter trimming. 981 reads were assigned at species level to RVB (strain GCZ04) during read classification. The genotype constellation of the strain was found to be typical for swine viruses and the nucleotide identities of the segments of the strain were within the cut off values established for different genotypes. The remaining viral reads were annotated to porcine kobuvirus (PKV) (23 reads). Furthermore, the analysis revealed presence of the following taxa: Qubevirus faecium (334 reads), and Gaprivervirus (1 read).

Conclusions: Our study reports the first molecular detection of porcine RVB in faecal samples collected from pigs reared on a commercial swine farm in Poland. Since the material was obtained from clinically affected animals and RVB was proven dominant among viral reads obtained during the NGS investigation, the virus may be considered as a potential causative agent of diarrhoeal disease in suckling piglets. Moreover, our research provides the tenth porcine RVB genome in Europe. The identities and phylogenetic clustering of different segment sequences to those from North America, Asia or Europe may suggest a complex evolutionary history of the Polish strain.

Background: Disease-associated Streptococcus suis (DASS) refers to strains of S. suis that cause systemic infections in swine, including meningitis, septicemia, and pneumonia, resulting in significant economic losses and welfare concerns. Effective control of DASS on swine farms requires accurately detecting these pathogenic strains and identifying carrier animals and reservoirs. In this study, the dynamics of DASS colonization in clinically healthy dams, their piglets, and the surrounding environment was investigated on two commercial swine farms using novel qPCR assays: one targeting the recN gene (species-specific) and another targeting the SSU_RS01130 gene (associated with disease-causing strains). The objectives were to identify optimal sampling sites, assess the impact of dam parity, and understand the disease dynamics of DASS to provide a baseline for future studies to improve control strategies.

Results: Gilts and their piglets consistently exhibited higher DASS colonization compared to sows, underscoring the need for parity-based interventions. Tonsil and nasal samples were the most reliable for DASS detection in dams, while udder, fecal, and the environmental sites may serve as potential reservoirs for piglet colonization. All piglets were colonized with S. suis within 24 h of birth, but not all carried DASS; notably, a substantial proportion, particularly on Farm 1, remained DASS-negative at weaning. DASS detection in piglets decreased at day 7 and rebounded by day 21, reflecting dynamic colonization patterns. Farm-specific differences highlighted the impact of management practices and strain variation, with Farm 2 showing consistently higher DASS prevalence and persistence. Notably, the consistent absence of DASS in some litters suggests that targeted management, good hygiene, and dam-related factors such as parity can effectively reduce transmission risk.

Conclusion: This study highlights how parity, sampling site selection, and environmental reservoirs may influence DASS colonization and persistence. This study generated valuable data that can inform future investigations aimed at improving DASS control strategies, including parity segregation, batch farrowing, maternal immunity enhancement, improved colostrum management, and hygiene protocols. Additionally, the findings support the potential refinement of Medicated Early Weaning (MEW) strategies, integrating antimicrobial use, hygiene improvements, and dam-focused interventions to reduce DASS prevalence. The novel qPCR assays offer a reliable, culture-independent surveillance tool for DASS detection, enabling veterinarians to develop evidence-based programs for early detection of, and to mitigate the impact of DASS in swine herds.