Self-emulsifying drug delivery systems (SEDDS) containing Cymbopogon citratus essential oil: Enhancing the stability and acaricide efficacy against Rhipicephalus (Boophilus) microplus.

The objectives of this study were to develop a self-emulsifying drug delivery system (SEDDS) to enhance the stability and efficacy of Cymbopogon citratus essential oil or lemongrass oil (LEO) against cattle tick larvae and engorged females. The system with the highest oil loading in SEDDS was composed of LEO (23.33%w/w), Tween 80: SGKH 4000 in a 2:1 ratio as surfactant (66.67%w/w), and propylene glycol as co-surfactant (10%w/w). The selected SEDDS-LEO has a particle size of 18.78 nm with a narrow size distribution (polydispersity index of 0.27). Notably, the stability of SEDDS was superior to that of the original oil, both during long-term storage and under accelerated conditions. SEDDS-LEO at oil concentrations ranging from 1.458% to 5.833% w/v showed a significantly higher percentage of egg-laying reduction against adult ticks compared with the original oil at the same concentrations (p < 0.05). Furthermore, SEDDS-LEO demonstrated greater larvicidal efficacy than the original oil, with lower LC50 and LC90 values of 0.91 mg/mL and 1.20 mg/mL, respectively, whereas the original oil's LC50 and LC90 values were 1.17 mg/mL and 1.74 mg/mL, respectively. Our findings indicate that SEDDS-LEO is a promising candidate for use as an acaricide in the control of tick populations in dairy cattle.

Different cellular and molecular responses of Bovine milk phagocytes to persistent and transient strains of Streptococcus uberis causing mastitis.

Streptococcus uberis is frequently isolated from milk collected from dairy cows with mastitis. According to the host's immunity, bacterial virulence, and their interaction, infection with some strains can induce persistent subclinical inflammation, while infection with others induces severe inflammation and transient mastitis. This study compared the inflammatory response of milk-isolated white blood cells (mWBCs) to persistent and transient S. uberis strains. Quarter milk samples were collected aseptically for bacterial culture from all lactating cows once a week over a 10-week period. A transient and noncapsular strain with a 1-week intramammary infection duration was selected from this herd, while a persistent and capsular S. uberis strain with an intramammary infection longer than 2 months from our previous study was selected based on an identical pulse field gel electrophoresis pattern during the IMI episode. Cellular and molecular responses of mWBCs were tested, and the data were analyzed using repeated analysis of variance. The results showed a higher response in migration, reactive oxygen species generation, and bacterial killing when cells were stimulated with transient S. uberis. In contrast, the persistent strain led to increased neutrophil extracellular trap release. This study also highlighted several important molecular aspects of mWBCs. Gene expression analyses by real-time RT-PCR revealed a significant elevation in the expression of Toll-like receptors (TLR-1, TLR-2, TLR-6) and proinflammatory cytokines (tumor necrosis factor-alpha or TNF-α) with the transient strain. Additionally, Streptococcus uberis capsule formation might contribute to the capability of these strains to induce different immune responses. Altogether, these results focus on the immune function of activated mWBCs which demonstrate that a transient strain can elicit a stronger local immune response and, subsequently, lead to rapid recovery from mastitis.

Comparison of the efficacy and perioperative pain between vessel sealing and suture ligation for median celiotomy in canine ovariohysterectomy.

Background and Aim: Vessel sealing (VS) is used widely in human medicine and veterinary practice during laparoscopic surgery; however, few studies have investigated VS in canine ovariohysterectomy (OHE) using the median celiotomy approach. This study aimed to compare the effect of VS and suture ligation (SL) on surgical time, blood loss, and perioperative pain in canine OHE through median celiotomy. Materials and Methods: Twenty-eight dogs were randomly and equally assigned into two groups that underwent surgery either by SL at both the ovarian pedicle and uterus or using a disposable VS device. The short form of the Glasgow composite pain scale (SF-GCPS) and the Colorado state university canine acute pain scale (CSU-CAP) were used to determine pain pre-operatively (baseline); at 30 min; and at 1, 2, 3, 4, 24, and 72 h post-operatively. Perioperative physiological parameters, surgical duration, and percentage of blood loss were recorded. Repeated measures analysis was performed to determine the differences in all parameters among time-related tasks and between both groups. A significant difference was defined at p < 0.05. Results: The duration from identification of the first ovary to uterus removal was shorter in VS than in SL (p < 0.05). No clinically relevant differences were found among physiological variables. Both groups showed higher SF-GCPS and CSU-CAP values after surgery compared with baseline. The SF-GCPS in SL at 1 h was higher than in VS (p < 0.05). Two dogs in the SL group required additional post-operative rescue analgesia. No differences were found between the groups in terms of blood loss. Conclusion: The use of a VS device in dogs undergoing OHE celiotomy decreased post-operative pain and shortened the perioperative time, making it an effective alternative technique for this common surgery. However, the VS device must be applied 2-3 times in the same location during the OHE procedure to prevent technical failure. This disposable device was reused up to 5 times for economic reasons without device failure. Soft tissue damage during OHE using the VS device should be investigated in a future prospective study.