[Use of free fatty acids in animal nutrition]

Effect of Black Soldier Fly (Hermetia illucens L.) Fat on Health and Productivity Performance of Dairy Cows

Due to the intensive development of technologies for obtaining protein, energy feed and biologically active supplements from insects, the feasibility and effectiveness of introducing these products into the rations of farm animals require further study. This research aims to study the possibility and effects of feeding dairy cows fat from the larvae of the black soldier fly (BSFLF). The composition and properties of the BSFLF have been studied. The research of the fatty acid composition of BSFLF showed a high content of saturated fatty acids, including 58.9% lauric acid. The experiment was performed on black-and-white cows at the beginning of lactation (control, D0 (n = 12) vs. experimental D10 (n = 12) and D100 (n = 12) groups, 10 and 100 g/head/day BSFLF, respectively. There was no negative effect of BSFLF feeding on the process of feed digestion. The pH of the rumen content decreased (6.80 ± 0.07 & 6.85 ± 0.09 vs. 7.16 ± 0.06, p < 0.05), with an increase in the number of infusoria (0.27 ± 0.03&0.37 ± 0.09 vs. 0.18 ± 0.03 g/100 mL, p = 0.16); there was an increase in the concentration of VFA in the rumen content of animals of the experimental groups by 2.1 (p < 0.05) and 3.81 (p < 0.01) (8.66 ± 0.46 & 10.37 ± 0.42 vs. 6.56 ± 0.29) mmol/100 mL. The average daily milk yield of Group D10 cows over the experimental period (d17−d177) was slightly higher than the control (by 4.9%, p = 0.24 vs. Group D0). At the same time, Group D100 cows showed a significant increase in natural-fat milk compared to controls (by 8.0%, p < 0.05 vs. Group D0) over the same experiment period. Analysis of the fatty acid composition of the milk of the experimental animals showed some changes in the fatty acid composition of milk under the influence of BSFLF feeding; these changes were especially noticeable in Group D10. Thus, it was found that feeding dairy cows BSFLF at different dosages leads to better indicators of pre-gastric digestion and productivity.

Digestive and metabolic utilization of lauric, myristic and stearic acid in cows, and associated effects on milk fat quality

In an experiment with 3 x 6 Brown Swiss cows, the effects of dietary supplementations (40 g/kg) of non-esterified lauric (12 : 0), myristic (14 : 0) and stearic acid (18 : 0) on digestibility, metabolisability, milk fat composition and melting properties were investigated. The diet consisted of forage and concentrate in a ratio of 3 : 2. Cows were fed the C18 : 0 supplemented diet for 10 days before treatment feeding started for a 15-day experimental period where, at the end, excreta were quantitatively collected and gaseous exchange was measured. The DM intake averaged 17.9 kg/d for the C14 : 0 and C18 : 0 diets and was reduced (P < 0.05) by 18% in the C12 : 0 diet. The realised intakes of total C12 : 0, C14 :0 and C18 : 0 amounted to 368, 391 and 617 g/d in the respective groups. The efficiency of ME utilization for lactation was higher (P < 0.001) in the C12 : 0 group than in the two other groups indicating differences in metabolism of C12 : 0 in comparison with C14 : 0 and C18 : 0. Shifts in dietary fatty acid supplementation were clearly reflected in the milk fat composition. Associated changes were elevated CLA and C18 : 1 trans when supplementing C12 : 0, and a high C18 : 1 to C16 : 0 ratio (P < 0.05) in the C12 : 0and C18 : 0 groups which resulted in an easier melting milk fat than with supplementary C14 : 0. Despite certain favourable effects of C12 : 0 in metabolic energy utilization and milk fat melting properties (relative to C14 : 0), more research is needed on how to improve its palatability for dairy cows.

The combined use of whole Cuphea seeds containing medium chain fatty acids and an exogenous lipase in piglet nutrition

In search for an alternative for nutritional antimicrobials in piglet feeding, the effects of adding whole Cuphea seeds, as a natural source of medium chain fatty acids (MCFA), with known antimicrobial effects, and an exogenous lipase to a weaner diet were studied. The foregut flora, the gut morphology, some digestive parameters and the zootechnical performance of weaned piglets were investigated. Thirty newly weaned piglets, initial weight 7.0 +/- 0.4 kg, were divided according to litter, sex and weight in two groups (control diet; Cuphea + lipase diet). The Cuphea seeds (lanceolata and ignea) (50 g kg(-1)) were substituted for soybean oil (15 g kg(-1)), Alphacell (25 g kg(-1)) and soy protein isolate (10 g kg(-1)) in the control diet. Also 500 mg kg(-1) microbial lipase was added to the Cuphea diet. The piglets were weighted individually on days 0, 3. 7, 14 and 16. Feed intake was recorded per pen during days 0 to 3, 3 to 7, 7 to 14 and 14 to 16. On day 7 five piglets of each experimental group were euthanized for counting the gastric and small intestinal gut flora and for gut morphology at two sites of the small intestine (proximal, distal). The results indicate a trend towards improved performances parameters by feeding Cuphea + lipase. The enzymic released MCFA (1.7 g kg(-1) fresh gastric contents) tended to decrease the number of Coliforms in the proximal small intestine, but increased the number in the stomach and distal small intestine. With Culphea, the number of Streptococci was significantly lower in small intestine, but not in the stomach, while the number of Lactobacilli was significantly lower in the distal small intestine and tended to be lower in the stomach and proximal small intestine. No differences between the diets were noted for the total anaerobic microbial load in the stomach or in the gut. Feeding Cuphea + lipase resulted in a significantly greater villus height (distal small intestine) and a lesser crypt depth (proximal and distal small intestine) and greater villus/crypt ratio depth (proximal and distal small intestine). The intra-epithelial lymphocyte (IEL) counts per 100 enterocytes were significantly decreased in the proximal small intestine and tended to decrease in the distal small intestine by feeding the Cuphea + lipase diet. Both phenomena are indicative for a more healthy and better functional state of the mucosa. Present results are in line with foregoing research, showing that manipulation of the gut ecosystem by the enzymic in situ released MCFA in the stomach and foregut can result in improved performances of the piglets, which makes the concept a potential alternative for in-feed nutritional antibiotics.

Comparative evaluation of rumen-protected fat, coconut oil and various oilseeds supplemented to fattening bulls. 1. Effects on growth, carcass and meat quality

Growth performance, carcass and meat quality were determined in 36 fattening Brown Swiss bulls fed with maize silage-hay-concentrate based rations supplemented with fats and various oilseeds. The concentrate diet in the control group contained only barley and soybean meal, while the treated groups included, as partial replacement of the concentrate, rumen-protected crystalline fat, coconut oil, whole crushed rapeseed, sunflower seed or linseed, providing additional 3% fat of total ration dry matter. Animals were housed in groups of six with one representative of each treatment in a monofactorial design and feed was offered using transponder controlled equipment. Daily gains were similar for control, protected fat, rapeseed and linseed treatments (1240 g/d on average), but were lower (P < 0.05) with sunflower seed (1135 g/d) and coconut oil (1038 g/d). Corresponding differences (P < 0.05) in carcass weights were observed. All fat supplemented groups had reduced rumen fluid protozoa counts (P < 0.05). Carcasses tended to be leaner with the fat supplements. Mostly no significant effects on other carcass quality (dressing percentage, conformation score) and meat quality traits (final pH, cooking loss, shear forces) as well as composition (dry matter, fat, collagen) occurred. Consequently, rumen protected fat and some oilseeds can be recommended to be fed to growing cattle as energy sources.