Validation of a technique for determining apparent digestibility in large (up to 5 kg) Atlantic salmon (Salmo salar L.) in seacages

In vivo and in vitro protein digestibility in juvenile bagrid catfish Mystus nemurus (Cuvier and Valenciennes 1840) fed soybean meal-based diets

“…Various collection methods were employed to collect samples of faeces including stripping (Glencross, Hawkins, Evans, Rutherford, Dods, Maas, McCafferty & Sipsas ), anal dissection (Peres et al . ) and anal suction (Percival, Lee & Carter ). However, these methods may underestimate the APD by including the undigested feed from the anal cavity.…”

Addition of yttrium oxide as digestibility marker by vacuum coating on finished pellets — A method for assessing digestibility in commercial salmon feeds?

“…This makes the estimates more vulnerable to variations in gastrointestinal evacuation rate between the marker and different nutrients than if faeces are collected from the water outlet. However, collection of faeces from the water column in a sea cage is practically impossible, and stripping has proven to be a good method (Austreng, 1978;Percival et al, 2001). Measures to minimize the error caused by the variation in gastric evacuation rate between different feed components, seen in Experiment 2, could be to feed the fish frequently or to time the stripping according to the last meals.…”

“…Faeces may be collected by different methods, including careful stripping of the fish (Austreng, 1978), dissection of the intestine or different ways of collection from the water outlet (Cho and Slinger, 1979;Choubert et al, 1979Choubert et al, , 1982Glencross et al, 2007). Stripping is the preferred choice for salmon in sea cages since collection of faeces from the water is not practically feasible (Percival et al, 2001). This method is also less sensitive to the physical structure and water stability of the faeces, factors known to be affected by dietary raw material composition, e.g.…”

Feeding in hatcheries

“…However, digestibility is a difficult measurement to make in large fish, and the most satisfactory approaches use physiologically inert markers with removal of the faeces directly from the fish at defined times after feeding (Percival et al, 2001). However, digestibility is a difficult measurement to make in large fish, and the most satisfactory approaches use physiologically inert markers with removal of the faeces directly from the fish at defined times after feeding (Percival et al, 2001).…”