Comparison of Two Hair Removal Methods in Sprague-Dawley Rats (Rattus norvegicus).

Rats commonly undergo surgery for research purposes. However, the effects of different methods of hair removal on wound healing and surgical site infections (SSI) in rats has not been evaluated. The current study evaluated 2 hair removal methods, clipping with an electric clipper and using a depilatory agent, and their effect on wound healing and SSI. Swabs for bacterial culture were obtained on Day 0 just after hair removal, after aseptic skin preparation, and on Days 1 and 3 before conducting skin biopsies to assess bacterial load and recolonization. Full-thickness punch biopsies were taken for histopathologic evaluation on Days 0, 1, 3, 7, and 10. The surgical incisions were assigned an ASEPSIS score on Days 1 and 3. The data revealed that the bacterial load was significantly higher with the depilatory method as compared with the clipper method, but only on Day 1. The histopathologic evaluation found no significant difference in wound healing between the 2 methods. Although the ASEPSIS score was significantly higher for the clipping method than for the depilatory method on Day 1, both techniques were equivalent by Day 3. We conclude that both hair removal methods are safe and efficacious components of aseptic technique in rats.

3D-printed Wash Station with Integrated Anesthesia Delivery Manifold for High-throughput Depilation of Laboratory Mice.

Depilation (that is, hair removal) is a necessary prerequisite for many small animal surgeries and optical imaging experiments. Over-the-counter depilatory creams are widely used, owing to their efficacy, safety, and low rates of skin irritation and infection. However, the use of these creams is generally messy and time-consuming and generates considerable waste. Furthermore, the process itself varies markedly among laboratories. Here we present a 3D-printed device that simplifies the depilation procedure by integrating 3 key elements: 1) a multiple-port, self-scavenging anesthesia manifold, 2) curved animal holders with flow-through slats, and 3) a removable waste collection tray. Reflecting insights gained from an international survey about depilatory lab procedures that highlighted the lack of standardized protocols, this apparatus is designed to improve the neatness, throughput, and safety of mouse depilation, resulting in efficient and repeatable processes that bolster the welfare of both researchers and subjects.

Dorsal shaving affects concentrations of faecal cortisol metabolites in lactating golden hamsters.

Breeding of golden hamsters is classically performed at thermal conditions ranging from 20 to 24 °C. However, growing evidence suggests that lactating females suffer from heat stress. We hypothesised that shaving females dorsally to maximise heat dissipation may reduce stress during reproduction. We thus compared faecal cortisol metabolites (FCM) from shaved golden hamster mothers with those from unshaved controls. We observed significantly lower FCM levels in the shaved mothers (F1,22 = 8.69, p = 0.0075) pointing to lower stress due to ameliorated heat dissipation over the body surface. In addition, we observed 0.4 °C lower mean subcutaneous body temperatures in the shaved females, although this effect did not reach significance (F1,22 = 1.86, p = 0.18). Our results suggest that golden hamsters having body masses being more than four times that of laboratory mice provide a very interesting model to study aspects of lactation and heat production at the same time.

Trial of human laser epilation technology for permanent wool removal in Merino sheep.

OBJECTIVE: To assess whether human laser epilation technology can permanently prevent wool growth in sheep. DESIGN: An observational study. METHODS: Two commercial human epilation lasers (Sharplan alexandrite 755 nm laser, and Lumenis LightSheer 800 nm diode laser) were tested at energies between 10 and 100 J/cm2 and pulse widths from 2 to 400 ms. Wool was clipped from flank, breech, pizzle and around the eyes of superfine Merino sheep with Oster clippers. After initial laser removal of residual wool to reveal bare skin, individual skin sites were treated with up to 15 cycles of laser irradiation. Behavioural responses during treatment, skin temperature immediately after treatment and skin and wool responses for 3 months after treatment were monitored. RESULTS: A clear transudate was evident on the skin surface within minutes. A dry superficial scab developed by 24 h and remained adherent for at least 6 weeks. When scabs were shed, there was evidence of scarring at sites receiving multiple treatment cycles and normal wool growth in unscarred skin. There was no evidence of laser energy level or pulse width affecting the response of skin and wool to treatment and no evidence of permanent inhibition of wool growth by laser treatment. Laser treatment was well tolerated by the sheep. CONCLUSIONS: Treatment of woolled skin with laser parameters that induce epilation by selective photothermolysis in humans failed to induce permanent inhibition of wool growth in sheep. Absence of melanin in wool may have contributed to the result.

[Comparison of four protocols for preoperative preparation in cattle]. / Comparaison de quatre protocoles de préparation préopératoire chez le bovin.

This study was designed to evaluate 4 preoperative skin preparations, that is, more specifically, to compare the efficacy of chlorhexidine gluconate (CG) and povidone-iodine (PI), as well as 2 hair removal techniques (clipper alone or clipper followed by razor) for preoperative skin preparation in cattle. The 4 protocols resulted in a significant decrease in the number of bacterial colony-forming units (cfu). Group 4 (clipping + shaving + CG) had a significantly lower number of preoperative cfu per gel plate compared with groups 1 (clipping + PI) and 3 (clipping + shaving + PI). Skin reaction frequency was significantly higher in groups 3 and 4 (47.8% for both protocols) than in groups 1 and 2 (clipping + PI or CG) (8.7% for both). Wound infection frequency was 4.3% (4/92) and no significant difference was observed between the 4 treatment groups. The 4 protocols tested were equivalent as to efficacy and satisfactorily decreased skin microflora. Clipping alone was shown to be preferable to clipping plus shaving as a method of hair removal in cattle, with fewer skin reactions and no more wound infections.

The use of high-energy electrons to depilate the breech of sheep.

The use of high-energy electrons for permanently depilating areas of sheep skin was evaluated. The most effective dose of electrons for depilation was 17.5Gy. Histological changes in skin treated at this dose were examined in one sheep over 18 months and in 5 sheep over 89 d. Effects of treatment on bodyweight gains and fleece growth were examined by comparing the productivity of a further 5 sheep treated on the breech with high-energy electrons, with that of conventionally mulesed sheep (n = 5) and untreated controls (n = 5). Electron treatment resulted in immediate death of cells in the germinative region of the wool follicle bulbs. Within 10 d of treatment the treated areas were completely depilated. Wool follicle shafts in the treated areas regressed rapidly towards the epidermis and remained quiescent for the whole trial (89 d). A sheep treated 18 months previously has remained largely depilated, although a few sparse fibres are present. Epidermal acanthosis and orthokeratosis were present at 26 d after treatment. The thickened stratum corneum then sloughed off, but the epidermis remained acanthotic for the entire trial. Sweat glands and most sebaceous glands were destroyed by the treatment and were replaced by fibrotic, avascular tissue in the dermis. In all other respects the external appearance of the electron-treated breech was similar to that of mulesed sheep. There were no apparent side-effects of treatment. Neither mulesing nor electron treatment altered weight gains or fleece growth rates.

Lipid composition of the bovine epidermis.

In contrast to skin surface or sebum lipid, cattle epidermis was found to contain a lower proportion of wax ester and unesterified fatty acid and a high proportion of triglyceride. The epidermal triglycerides differed significantly in their fatty acid composition from those of the skin surface and sebum. In particular they contained extremely low levels of linoleic acid. It is concluded that the skin surface triglycerides and most likely the other major lipid fractions of the bovine skin surface are derived mainly from sebum.