Improved quality of life and pain relief in mature horses with osteoarthritis after oral transmucosal cannabidiol oil administration as part of an analgesic regimen

Effect of orally administered cannabidiol oil on daily tonometric curve in healthy Italian Saddle horses

BACKGROUND

Phytocannabinoids have the potential to lower intraocular pressure in both normal and glaucomatous eyes and they have been tested in different animal species, but not in the horse. The present paper describes the tonometric curve of healthy adult Italian Saddle horses after oral administration of cannabidiol oil (CBD).

METHODS

CBD 20% was administered orally (oily solution) at the dose of 1 mg/kg to 8 adult horses and intraocular pressure (IOP) was evaluated by tonometric curve. Data were then compared to those of the same horses obtained the day before (blank) CBD administration.

RESULTS

15 minutes after CBD administration, IOP (time zero 27.3 ± 2.1 mmHg right eye; 24.6 ± 2.3 mmHg left eye) started to decrease (19.5 ± 5.2 mmHg right eye; 20.8 ± 2.4 mmHg left eye) and 1 hour later CBD it reached the minimum level in all horses (11.4 ± 7.5 mmHg right eye; 9.5 ± 5.8 mmHg left eye), remaining statistically significantly lower than normal values for the entire observation period (8 hours; 12.0 ± 7.9 mmHg right eye; 11.9 ± 7.8 mmHg left eye).

CONCLUSIONS

CBD 20% was effective to significantly reduce IOP in healthy adult Italian Saddle horses and may be an effective hypotensive agent to be implemented in case of primary or secondary glaucoma.

Effects of Cannabidiol Oil on Anesthetic Requirements in Cats: MAC Determination and Serum Profiling via Nanoscale Liquid Chromatography-Tandem Mass Spectrometry

Cannabidiol (CBD), a non-psychotropic cannabinoid derived from Cannabis plants, is increasingly explored for its potential therapeutic applications in veterinary medicine. This study aimed to evaluate the impact of CBD oil on the minimum alveolar concentration of isoflurane (MACiso) in cats. Sixteen healthy cats underwent isoflurane anesthesia, and the MACiso was determined using the tail-clamping technique both at baseline and 30 min after the administration of CBD oil (2 mg/kg) via a stomach tube. CBD administration resulted in a significant 11% reduction in the MACiso, from 1.77 ± 0.14% to 1.62 ± 0.21% (p < 0.001). Following CBD administration, heart and respiratory rates were elevated at the time of MACiso determination compared to baseline whereas other physiological parameters remained unchanged. Serum biochemical analysis conducted two weeks post administration revealed a significant decrease in blood urea nitrogen (BUN) levels while one cat exhibited a mild increase in alanine aminotransferase (ALT). Proteomic analysis identified 12 CBD-associated proteins in feline serum 30 min post administration, with CBDA and THCA synthases demonstrating significant upregulation. These findings indicate that CBD oil reduces anesthetic requirements in cats without inducing significant physiological disturbances. Further research is warranted to elucidate the underlying mechanisms of CBD's anesthetic-sparing effects and its implications in veterinary anesthesia.

Effects of hemp-based polyunsaturated fatty acid supplementation on membrane lipid profiles and reproductive performance in Martina Franca jacks

This study evaluates the impact of dietary supplementation with hemp-based polyunsaturated fatty acids (PUFAs) on the membrane lipid profiles and reproductive performance of Martina Franca jacks. Over a 90-day period, twelve donkeys were divided into a treatment group receiving hemp oil and a control group on a standard diet. Semen and blood samples were collected and analyzed at multiple time points for lipid composition and reproductive parameters. Results revealed that sperm motility improved significantly, increasing from 92.61% in the control group to 96.63% by Day 60 in the treatment group (p = 0.05). Normal sperm morphology also showed a significant enhancement, rising from 96.58% in the control group to 98.85% by Day 60 (p = 0.04). Conversely, gel-free semen volume decreased significantly in the treatment group, from 64.17 mL in the control group to 28.20 mL at Day 60 (p < 0.0001). Lipidomic analyses indicated an increased proportion of omega-3 PUFAs, such as eicosapentaenoic acid (EPA; 0.08% in the control group to 0.20% by Day 60, p < 0.0001), in sperm membranes, alongside a reduction in the peroxidation index (264.11 in the control group to 86.53 in the treatment group, p < 0.0001). These changes suggest improved membrane fluidity and oxidative stability. These findings underscore the potential of hemp oil as a dietary supplement to enhance reproductive outcomes in donkeys, with broader implications for livestock management.

Soybean and avocado unsaponifiables: a review of their potential use in the treatment of osteoarthritis

Recent research has shown that Avocado-Soybean Unsaponifiables (ASU) greatly reduce the symptoms of osteoarthritis (OA). It's yet unknown exactly how ASU works, however, it has been demonstrated to have analgesic and anti-inflammatory effects. These qualities can potentially lessen the need for non-steroidal anti-inflammatory medicines (NSAIDs) and their secondary effects. This review aims to examine the current literature on ASU, focusing on their efficacy, mechanism of action, and potential utility in treating OA for managing chronic pain associated with this condition. The literature review was conducted manually through Pubmed, Scopus and Web of Science (WOS) databases, covering studies from 2000 to 2022 with terms like "osteoarthritis," "OA," "animal models," "ASU," and "soy/avocado." Two reviewers independently screened each article using inclusion and exclusion criteria and categorized the studies into in vitro, preclinical, and clinical groups. According to in vitro research, ASU affect the regulation of molecules related to OA, increasing structural elements like collagen and aggrecan and decreasing pro-inflammatory mediators. Although results vary, pre-clinical research in different animal models has demonstrated positive effects, such as ameliorating histopathological changes and reduced inflammation. Despite some discrepancies regarding structural changes in the joints, clinical trials typically demonstrate symptom relief and slow down the disease progression. While ASU demonstrates significant promise in alleviating OA symptoms and reducing reliance on NSAIDs, further research is essential to fully understand its mechanisms of action. More studies are needed to determine the precise pathways through which ASU exerts its effects and to establish the most effective dosages for its administration, either alone or in combination with other treatments.

Assessing Facial Thermal Nociceptive Response in Female Dogs After Elective Ovariohysterectomy Anesthetized with Isoflurane and Treated with Cannabidiol and Meloxicam Analgesia

Pain management requires the identification of certain indicators to recognize pain. Various tools have been suggested to achieve an objective evaluation, including infrared thermography (IRT). The objective of this study was to assess the facial thermal nociceptive response produced by the use of cannabidiol (CBD) alone and in combination with meloxicam in female dogs undergoing elective ovariohysterectomy anesthetized with isoflurane. Sixty-four female dogs of different breeds were randomly distributed into four study groups according to the treatment received. G1: Placebo group (n = 16); G2: Group receiving intravenous meloxicam as premedication (0.2 mg Kg-1) and every 24 h postoperatively 0.1 mg Kg-1 (n = 16); G3: Group treated with CBD (n = 16) at a dose of 2 mg kg-1 orally every 12 h; and G4: Group medicated with the combination of both treatments (n = 16). All treatments were administered for 48 h postoperatively. After the anesthetic surgical procedure, radiometric images were captured using IRT and physiological parameters during the events EBasal, E30min, E1h, E2h, E3h, E4h, E8h, E12h, E24h and E48h. Overall, it was found that the high, medium and low temperatures of the thermal windows of the eye, upper eyelid and lower eyelid, as well as the average temperature of the lacrimal gland in G1 between events, were significantly lower at E30min, E1h and E2h compared to EBasal (p = 0.01). Among treatments, a significantly higher temperature was observed in groups G2, G3 and G4 compared to G1 (p = 0.001) in the thermal windows of the upper eyelid, lower eyelid, lacrimal gland and ocular areas. Regarding physiological parameters, heart rate (HR) was higher in G1 compared to the animals in G2, G3 and G4 (p = 0.03). The respiratory rate (RR) was significantly lower in all four study groups during the postoperative events compared to their respective EBasal (p < 0.05), while among treatments, G2, G3 and G4 had a lower RR compared to G1 (p = 0.03). Mild hypothermia was observed in all study groups at E30min and E1h compared to EBasal (p = 0.001). No significant correlation was found between the temperatures of the assessed thermal regions and the physiological traits. In conclusion, CBD, whether administered alone or in combination with meloxicam, demonstrated comparable analgesic efficacy, which could control nociceptive cardiorespiratory and hemodynamic autonomic responses, as there were no significant changes in the facial thermal response between treatments G2, G3 and G4.

Analgesic efficacy of tapentadol in chronic joint disorders in horses: plasma serotonin concentration and adrenocortical response as biomarkers of pain-induced stress

The study aimed to evaluate the analgesic efficacy of tapentadol in horses, by determining plasma serotonin concentration and adrenocortical response, as biomarkers of pain stress in chronic joint disorders. Thirty-six horses (20 females and 16 males) were divided into three groups of 12 subjects each: group A, osteoarthritis (OA), grade 3-4 lameness; group B, OA, grade 5 lameness; and group C, no OA, no lameness, were enrolled. The orthopedic examination included flexion tests, and radiological and ultrasound examinations. The degree of lameness has been estimated from 0 to 5 according to the American Association of Equine Practitioners (AAEPs). Heart and respiratory rates (HR and RR) and blood pressure were recorded. Serotonin concentration and circulating cortisol levels were determined at baseline and the end of every week for 4 weeks. Biochemical parameters were recorded at baseline and the end of treatment with tapentadol. Subjects with OA were treated with tapentadol 0.5 mg kg-1. The response to painful stimulus on flexion tests was evaluated using the modified numeric pain rating scale (modified NRS 0-7) from baseline and the cumulative pain score (CPS 0-4) after the first week of treatment with tapentadol. The lameness decreased throughout the timeline in both groups (score from 3-4 to 1 in group A and score from 5 to 1 in group B) (p < 0.05). The NRS score decreased throughout the timeline (p < 0.05), from mild pain to no pain in group A (score 1-3 to 0) and from moderate pain to no pain in group B (score from 4 to 0). Physiological variables remained within the physiological range throughout the timeline. Cumulative pain scores ranged from 0.5 to 4 in group A and 1.5 to 7 in group B (p = 0.008). Serotonin concentrations remained unchanged throughout the timeline in all groups (p = 1.000) but in the OA groups, the concentrations were lower than control (p < 0.001). Circulating cortisol levels were reduced compared to baseline in subjects treated with tapentadol (p < 0.001). Tapentadol is effective in OA pain management in horses. Serotonin and cortisol may be utilized as biomarkers in the pain stress response. Serotonin can also determine the state of wellbeing of patients.

Role of cannabidiolic acid or the combination of cannabigerol/cannabidiol in pain modulation and welfare improvement in horses with chronic osteoarthritis

Cannabidiol (CBD) is a non-psychotropic cannabinoid obtained from hemp (Cannabis sativa L.) used for pain management in companion animals including horses. The present study aimed to evaluate the efficacy of cannabidiolic acid (CBDA) and cannabigerol/cannabidiol oil (CBG/CBD) oral administration in alleviating pain in adult horses affected by chronic osteoarthritis (OA). Twenty-four horses (10 geldings and 14 mares), aged between 11 and 18 years old, were equally divided into two groups. One group received CBDA 15% oil and the other group received CBG/CBD oil (CBG20%-CBD10%) for 14 consecutive days. A standard dose of 0.07 mg/kg was chosen based on the mean body weight of 450 ± 28 kg. Horse Chronic Pain Scale (HCPS) and physiological parameters monitoring heart rate (HR), respiratory rate (RR), arterial blood pressure (systolic arterial pressure- SAP, diastolic arterial pressure- DAP) were assessed before (T0) and every day for the entire administration (T1-T14). Blood samples were collected for the evaluation of complete hemogram, Leukocyte subpopulation identification and counting and leukocyte differentiation antigens CD4 and CD8 at the day before the administration (T0) and every 7 days (T7 and T14). A reduction of HCPS pain scale scores and the number of WBC, monocytes and neutrophils and CD8 was observed with both CBDA and CBG/CBD treatment. No statistical differences were found in the physiological parameters. No subject required rescue analgesia or showed any adverse effects. The results of this study showed that oral administration of both CBDA and CBG/CBD oil may promote pain reduction in adult horses affected by chronic OA.

Assessment of the nociceptive response to the use of cannabidiol alone and in combination with meloxicam through infrared pupillometry in female dogs undergoing elective ovariohysterectomy

The negative effects of pain are a constant concern in the surgical management of animals, leading to the search for new drugs or more effective analgesic protocols to control this negative emotion. This study aimed to evaluate the nociceptive response of cannabidiol (CBD) alone and in combination with meloxicam using infrared pupillometry in female dogs undergoing elective ovariohysterectomy (OVH) under isoflurane anesthesia. A total of 60 female dogs of different breeds were included. These dogs were randomly assigned to four study groups according to the treatment: Control Group (G0: n = 15) receiving saline solution; group premedicated with meloxicam at a dose of 0.2 mg Kg-1 IV (GMelox: n = 15). Postoperatively this drug was used at 0.1 mg Kg-1 IV every 24 h; the CBD-treated Group (GCBD: n = 15) at a dose of 2 mg Kg-1 orally in the preoperative. Postoperatively was administrated every 12 h; and the Group premedicated with the combination of meloxicam and CBD (GMelox/CBD: n = 15) Meloxicam at a dose of 0.2 mg Kg-1 IV preoperatively, and 0.1 mg Kg-1 IV during the postoperative. CBD at a dose of 2 mg Kg-1 orally in the preoperative, and every 12 h in the postoperative. Treatments were administered for 48 postoperative hours. After OVH, the pupillary neurologic index, pupillary size, minimum diameter (MIN), percentage change, constriction latency (Lat), constriction velocity, and maximum constriction velocity were recorded as pupillometric variables in both eyes during events (E): Baseline (30 min before drug administration), E30 min, E1h, E2h, E3h, E4h, E8h, E12h, E24h, and E48h. The Short-Form of the Glasgow Composite Measure Pain Scale (GCMPS-SF) was used to assess pain during the same events. Overall, it was observed that the pupillometric variables Size, MIN., and Lat. were significantly higher in G0 compared to the other groups during E30 min, E1h, and E2h (p = 0.03), indicating greater pupil dilation in G0 animals. Additionally, no statistically significant differences were observed in GCMPS-SF between GMelox, GCBD, and GMelox/CBD during the postoperative period (p > 0.05). In contrast, the scores were statistically different compared to G0 (p = 0.00001), where all animals in this group received rescue analgesia at 2 h post-surgery. According to pupillometry and scores on the GCMPS-SF scale, it was observed that monotherapy with cannabidiol provides a similar analgesic effect to meloxicam alone or in combination with cannabidiol to manage acute pain in dogs. Similarly, these findings suggest that infrared pupillometry could be a tool for recognizing acute pain in dogs.

Pharmacokinetics behavior of four cannabidiol preparations following single oral administration in dogs

Cannabidiol (CBD) is a natural phytochemical agent and one of the most abundant found in Cannabis sativa. It is known to exhibit pharmacological properties on various condition such as relieving-inflammation, pain, epilepsy, and anxiety effect. There has been an increasing trend globally in the use of CBD as a supplement in pets. Consequently, there are various CBD products being marketed that are specifically available for pets. Veterinarians and pet owners are concerned that following ingestion, different CBD formulations may result in a CBD level circulating in the blood that may affect the safe use and efficacy of CBD in pets. Several pharmacokinetics studies in animals have been mainly conducted with an oily form of CBD. To date, there is a lack of data regarding direct comparisons in animals among the CBD plasma kinetic profiles from an oral administration of the various preparation forms. Therefore, the current study evaluated and compared the plasma CBD levels from a single oral administration using four different CBD preparations-liquid (an oil-based form, a nanoemulsion form, or a water-soluble form) or a semi-solid form (as CBD mixed in a treat) in dogs. In total, 32 healthy, crossbreed dogs were randomly assigned into 4 groups and treated according to a 1-period, 4-treatment parallel-design. The three liquid forms were dosed at 5 mg/kg body weight, while the single semi-solid form was given at 50 mg/treat/dog. The results showed that the CBD plasma profile from the administration of a water-soluble form was comparable to that of the oil-based group. The nanoemulsion-based form tended to be rapidly absorbed and reached its peak sooner than the others. However, the CBD in all preparations reached the maximum plasma concentration within 3 h post-dose, with an average range of 92-314 μg/L. There were significant differences among certain parameters between the liquid and semi-solid forms. This was the first study to provide pharmacokinetics data regarding CBD in water soluble, nanoemulsion-based, and semi-solid forms for dogs as companion animals. The current data should facilitate the scrutiny of CBD plasma profiles based on different formulations via an oral route in dogs.