Sampling avian adipose tissue: assessing a nondestructive biopsy technique

Abstract

Adipose tissue samples can provide valuable information about the physiology, foraging ecology, and toxicology of birds. However, despite these varied applications, to date, no procedure for taking adipose samples from live birds has been described in detail, nor assessed for potential adverse effects. We describe a nonlethal method for collecting adipose tissue from adults and chicks of Black-legged Kittiwakes (Rissa tridactyla), Common Murres (Uria aalge), and Northern Fulmars (Fulmarus glacialis), and assess the short-and longer term effects of the procedure. Biopsies were carried out in the field using topical anesthetic and samples were taken from the synsacral region. Only two of 283 birds sampled (0.7%) had too little adipose tissue to be sampled successfully. Thirty-two kittiwakes were recaptured at varying intervals after the procedure (3-50 d) and the biopsy site inspected carefully. No signs of infection were observed and wounds healed completely within 6 d. Compared to birds captured for routine banding, biopsied kittiwakes showed neither greater weight loss nor reduced breeding success in the year of sampling. Similarly, recapture rates of biopsied birds in subsequent years were similar to those of individuals that had been blood sampled or banded. Our results suggest that collecting samples of adipose tissue by nondestructive biopsy has no more effect on birds than taking blood samples via syringe. Thus, we recommend nondestructive adipose tissue sampling via biopsy as an effective alternative to lethal methods in studies of wild birds.

Trace me if you can: the use of intrinsic biogeochemical markers in marine top predators

“…For such molecules, fatty tissues (eg hypodermic fat) would be the best choice; in the same way, trace metals mainly attached to metallothioneins are concentrated principally in liver, kidney, and muscle, although some metals, such as Hg and lead (Pb), can also be excreted in keratinous or calcified tissues. Although some organs can only be sampled through invasive procedures, many keratinous tissues can be sampled without any detrimental effects; non-destructive biopsy of fat from free-living animals is also feasible in some cases (Owen et al 2010). In addition, recent analytical improvements allow for the analysis of virtually all tracers via minimally invasive procedures, such as blood sampling (Henriksen et al 1998;; Williams and Buck 2010).…”

Analysis of fatty acids and fatty alcohols reveals seasonal and sex-specific changes in the diets of seabirds

“…The blood was immediately transferred to a 167 heparinised cryovial and stored below -70°C in a liquid nitrogen dry shipper within 4 hours 168 of collection to minimise oxidation of lipids. Adipose tissue was sampled from guillemots 169 using the previously described biopsy method which has been shown to be comparable in 170 terms of invasiveness to taking blood samples by syringe (Owen et al 2010) and involves 171 making a small (0.5cm long and 1-2mm deep) incision just through the skin to sample the 172 adipose tissue that lies just beneath it. Adipose samples were folded into clean sections ofaluminium foil to make a small packet which was itself put inside a cryovial and stored below 174 -70°C.…”

A non-lethal biopsy technique for sampling subcutaneous adipose tissue of small and medium-sized birds

“…Owen et al. () performed the biopsy in the synsacral region. However, songbirds and shorebirds accumulate fat in the synsacral region only at a late stage of fattening (Prater , Kaiser ).…”

“…) have sampled adipose tissues of seabirds by non‐destructive biopsy, only Owen et al. () reported details about sampling adipose from the synsacral region of adult and nestling Black‐legged Kittiwakes ( Rissa tridactyla ), Common Murres ( Uria aalge ), and Northern Fulmars ( Fulmarus glacialis ) (the smallest individuals sampled were ∼ 250‐g Common Murre chicks). These authors suggested that smaller birds (<250 g) could be biopsied using a similar method, but small birds may have little fat in the synsacral region (Blem ).…”

“…Owen et al. () assessed the healing process for Black‐legged Kittiwakes, but the time interval between the biopsy procedure and recapture of birds to assess body mass change (3–20 d) and healing of biopsy wounds (3–50 d) varied. Although such general evaluation may be adequate for large birds, a closer evaluation of wound healing and bird health is important during the first days after the biopsy for small and medium‐sized birds, given their greater susceptibility to problems (stress, hypothermia, or blood loss) during handling and biopsy procedures (Whittow ).…”