The utilization of animal donors of rumen fluid for laboratory experiments can raise ethical concerns, and alternatives to the collection of rumen fluids from live animals are urgently requested. The aim of this study was to compare the fresh rumen fluid (collected at slaughter, W) with that obtained from a continuous fermenter (RCF) and three methods of rumen fluid preservation (refrigeration, R, chilling, C, and freeze-drying, FD). The fermentability of different inoculum was evaluated by three in vitro tests (neutral detergent fiber (NDF) and crude protein (CP) degradability and gas production, NDFd, RDP and GP, respectively) using six feeds as substrates. Despite the two types of inoculum differed in terms of metabolites and microbiota concentration, the differences in vitro fermentability between the two liquids were less pronounced than expected (−15 and 20% for NDFd and GP when the liquid of fermenter was used and no differences for RDP). Within each in vitro test, the data obtained from rumen and from fermenter liquids were highly correlated for the six feeds, as well as between W and R (r: 0.837–0.985; p < 0.01). The low fermentative capacity was found for C and, particularly, FD for liquids. RCF could be used to generate inoculum for in vitro purposes and short-term refrigeration is a valuable practice to manage inoculum.

Cull dairy cows are important contributors to total beef production in the USA and in Europe. Hempseed cake is a by-product of oil production and it is rich in unsaturated fatty acids (FA). This study aimed to investigate the effect of adding hempseed cake to the diet of Italian Simmental (IS) cull dairy cows on performances and meat quality. Twenty-six cull dairy cows were divided into three dietary groups: hay-based, corn silage-based and pasture-based diets. Within each group, the animals were equally divided into two treatments according to the protein source of the concentrate: hempseed cake (HEMP) or soybeans meal (SB). The trial lasted four months. HEMP showed similar in vivo performance and carcass characteristics, such as average daily gain (p > 0.05) and dressing percentage (p > 0.05), compared with SB. Meat characteristics, such as ether extract content and Warner–Bratzler shear force, were also similar between experimental groups (p > 0.05). Considering FA composition, HEMP showed similar saturated FA and polyunsaturated FA content (p > 0.05) but lower desirable fatty acids (p < 0.05) content and a tendentially lower hypocholesterolemic/hypercholesterolemic ratio (p < 0.10) than SFA. Hempseed cake can substitute soybean in the diet of cull dairy cows without effects on performance or meat quality.

Heat stress is one of the most important problems that dairy cows have to face and the use of cooling systems is becoming more and more important. The first reaction that has the animal to cope with the environmental variations is to modify its behaviour. This study was aimed to investigate the effect of heat stress and a cooling system on the feeding behaviour of Italian Holstein Friesian dairy cows in late lactation. Two experiments were performed. In the first experiment, eight dairy cows were firstly kept 7 d under thermoneutral condition, and then under mild heat stress (temperature humidity index, THI, ranging between 72 and 78) for others 7 d. The second experiment consisted of 8 dairy cows used in a two-period cross-over design where the treatment was the use or not of a sprinkler system for cooling cows under mild heat stress. Cows were equipped with a noseband pressure sensor able to detect rumination and eating time, number of rumination and eating chews, number of rumination boluses and rumination intensity. Heat stress reduced rumination time, number of rumination chews and boluses (p < .05), and tended to reduce the number of eating chews (p < .10). Cooled cows increased rumination and eating time (p < .05), rumination intensity (p < .01), and the number of rumination and eating chews (p < .05). In conclusion, feeding behaviour was deeply influenced even by mild heat stress, which was effectively improved by the use of a sprinkler system.

Thirty five Duroc x Large White (DUxLW) and 43 Commercial Hybrid x Large White (CHxLW) were fed two diets differing for the content of crude protein (CP), with the aim to evaluate the effects of these diets on growth, carcass and thigh traits. Pigs were allotted to two groups and fed high protein (HP) and low protein (LP) diet. Within each dietary group, 3 diets were formulated, for the initial phase of growth (from 79 to 112 days, 17.3% and 15.4% CP as fed basis for the HP and LP diet, respectively), for the intermediated phase of growth (from 113 to 196 days, 15.1% and 13.7% CP as fed basis for the HP and LP diet, respectively) and for the finishing period (from 197 to 272 days, 13.4% and 11.4% CP as fed basis for the HP and LP diet, respectively). HP diets were supplemented with Lysine, LP were supplemented also with Methionine and Threonine. Pigs were slaughtered at nine months of age. Body weight (BW), average daily gain, total feed intake and feed conversion ratio were not affected by diet. Carcass weight, thigh weight, backfat and lean thickness and lean percentage (Fat-O-Meater, FOM) were not affected by dietary treatments, whilst backfat thickness and FOM were significantly higher (P<0.01) in DUxLW and CHxLW pigs genotype respectively. A reduction of about 15% (12% to 17%) of the dietary CP recommended by nutritional requirements does not affect the main productive performances and carcass characteristics of pigs slaughtered at around 160 kg of BW.

Aims: To formulate an artificial nectar for long-term maintenance of captive hummingbird, to measure the metabolizability of nutrients in the artificial nectar and to evaluate the effects of dietary fiber (inulin) addition on its digestive utilization. Study Design: Two groups of seven hummingbirds randomly distributed in two diets with different levels of inulin (0-7% DM). Methodology: The trial was conducted on two groups of seven non-reproductive Amazilia amazilia averagely weighing 4.0 g, giving nectar containing about 179 g/l dry matter (DM). DM content of sucrose and hexoses was 92.3%, (0.75 M), that of crude protein (CP) 4.3% and fat (EE) 2.3%. Inulin was added in the ratio of 7 g/100 g, as fed, of nectar powder. The experiment lasted 24 days; the birds were separately housed in experimental cages. Results: The daily DM intake of hummingbirds was about 2054 mg/d and upraised by 14%, to 2348 mg/d, when inulin was added to the nectar; the energy intake averaged 34 kJ/d. The average metabolizabilities of nectar were about 94% for DM and energy, 98.4% for sugars, 57% for CP and 44% for EE. The absorption of DM, sugars, energy and protein were statistically reduced by inulin addition, instead that of ash increased. From the balance trial it results that about one third of inulin should undergo a fermentation in the intestine. Adjustment of sugar and protein contents and of protein quality to hummingbirds’ species and rearing environment should be useful.