Possibility of fat addition in the rabbit diets

Feeds of animal origin in rabbit nutrition – a review

Rabbits are classified as obligate herbivores. However, under natural conditions, some members of the family Leporidae incorporate animal products into their diets. Therefore, it seems biologically justified to supplement the diets of farmed rabbits with feeds of animal origin as sources of protein, fat and minerals. The aim of this review was to describe, from a historical perspective, the use of various feeds of animal origin in rabbit nutrition. The applicability of by-products from mammal, poultry, fish and invertebrate processing for rabbit feeding was evaluated, including the future prospects for their use. A review of the available literature revealed that various animal-based feeds can be valuable protein sources in rabbit diets, but their inclusion levels should not exceed 5-10%. Studies investigating their efficacy have been conducted since the 1970s. In some regions of the world, the use of animal-derived protein in livestock feeds was prohibited due to the risk of spreading bovine spongiform encephalopathy (BSE). However, the interest in animal by-products as protein sources in livestock diets is likely to increase since the above ban has been lifted.

Animal Fats in Rabbit Feeding – A Review

The purpose of this article is to overview the history of feeding rabbits with different types of animal fats, and to discuss their effects on rabbit performance and quality of their products. Other aspects of the inclusion of various animal fats in rabbit diets are also described. This article is based on the analysis of relevant scientific literature and presents animal fats fed to rabbits, such as beef tallow, butter, pork lard, poultry fat, fish oil, krill oil, oil extracted from insect larvae, mixtures of various animal fats, and mixtures of animal and vegetable fats. The reported papers describe the effect of fats on growth performance, lactation, rearing performance, meat quality, and health status of rabbits. It is notable that in many cases, various animal fats were often an integral part of numerous diets or were included in control diets. The presented information demonstrates that animal fat can be fed to rabbits at 2–4% of the diet without negative effects on reproductive performance, growth performance and quality of meat obtained. Rabbits were used as model animals in many studies in which fat was added to balance the diets and to increase their energy value, especially when investigating various cardiovascular and obesity-related diseases.

Final Report on the Safety Assessment of Hydrogenated Cottonseed Oil, Cottonseed (Gossypium) Oil, Cottonseed Acid, Cottonseed Glyceride, and Hydrogenated Cottonseed Glyceride

Hydrogenated Cottonseed Oil, Cottonseed (Gossypium) Oil, Cottonseed Acid, Cottonseed Glyceride, and Hydrogenated Cottonseed Glyceride are cosmetic ingredients derived from Cottonseed Oil and used as skin-conditioning agents and surfactants. Non-oils known to be toxic that may be found in cottonseed oils include gossypol, aflatoxin, and cyclopropenoid fatty acids (CPFA). Toxic heavy metal and/or polychlorinated biphenyl (PCB) or other pesticide contamination is also possible. Cottonseed Oil was nontoxic in acute oral toxicity studies in rats. In a short-term study, rabbits that had been fed 2% Cottonseed Oil for 7 weeks had significantly lower blood chemistry parameters (compared to wheat bran controls) and significantly more stored hepatic vitamin A (compared to rabbits fed other fats). Cottonseed Oil controls used as vehicles in two parenteral studies produced negative results. Hydrogenated Cottonseed Oil tested in formulation did not produce dermal or ocular irritation in rabbits. An oral-dose reproductive study tested up to 30% Cottonseed Oil (with 1% CPFAs) and reported no adverse effects on sexual maturity and reproductive performance of the F0 generation; changes were noted in the F1 generation but reproductive capacity was not altered. Parenteral-dose reproductive studies reported no adverse effects. Cottonseed Oil was not mutagenic. Cottonseed Oil did not induce aberrant crypt foci when given orally to mice, but in other studies, it increased the incidence of spontaneous mammary tumors in rats and mice. Mice fed 20% Hydrogenated Cottonseed Oil during induction and promotion of photocarcinogenesis had significantly lower tumor incidence compared to mice fed 20 % sunflower oil. Hydrogenated Cottonseed Oil in formulation (up to 21 %) was neither an irritant nor sensitizer in clinical studies. Limited clinical data indicated that Cottonseed Oil does not contain allergic protein. Based on the available data, it was concluded that these ingredients may be used safely in cosmetic formulations if established limits on gossypol, heavy metals, and pesticide concentrations are not exceeded.

[The applicable merit of untreated, HCl-treated and partly-hydrolysed straw meal in the feeding regimen of piglets after early weaning. 4. Histological findings in the digestive epithelium of the piglet]

In studies with piglets of the country race the applicability of variously treated straw materials was tested in comparison with conventional concentrate feeding (I) after an early weaning date (30th-35th day of life) over an 8-week period (1st-8th week of keeping). In the rations containing 10% straw (straw-concentrate mixtures), untreated (II), HCl treated (III: HCl treatment without steaming) and partly hydrolyzed straw meal (IV: HCl treatment with subsequent steaming) were used in the feeding. Samples were taken of 4 killed animals each in the 2nd and 8th weeks of keeping for the qualitative histologic assessment of palatum durum, oesophagus and stomach, duodenum and caecum, colon ascendens, colon descendens and rectum. Although significantly lower pH values in the stomach were registered after the feeding of feed mixtures III and IV due to increased acidity (pH value decrease by 1.3 to 1.5 units) in comparison to the values in I and II, the lamina epithelialis of the palatum durum remained intact in all groups and without any signs of cauterization. Equally, considerable changes in the comparison of the feeding groups could not be detected in the structures of the oesophagus and the stomach walls or in the qualitative histologic assessment of the duodenum and the caecum. However, there were clearly distinguishable group specifics with regard to the formation of lymphoreticular tissue in the stomach and for the colon ascendens.(ABSTRACT TRUNCATED AT 250 WORDS)