Dietary protein and energy supplies differentially affect resistance to parasites in lactating mammals

• Published in: British journal of nutrition Vol. 106; no. 8; pp. 1207 - 1215
• Main Authors: Sakkas, Panagiotis, Houdijk, Jos G. M., Jones, Leigh A., Knox, Dave P., Kyriazakis, Ilias
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 28-10-2011; CABI Pub
• Subjects: Animal reproduction; Animals; Biological and medical sciences; dietary protein; Dietary Proteins - administration & dosage; eggs; energy; Energy Intake - immunology; excretion; Feeding. Feeding behavior; Female; foods; Fundamental and applied biological sciences. Psychology; immunity; Immunology; lactation; Lactation - immunology; Lactation - physiology; Larvae; litter size; Mammals; metabolizable energy; Nippostrongylus - immunology; Nippostrongylus - pathogenicity; Nippostrongylus brasiliensis; Nutrition research; Nutritional Immunology; Parasite Egg Count; Parasites; Parasitic Diseases, Animal - immunology; Parasitic Diseases, Animal - parasitology; Parasitic Diseases, Animal - physiopathology; Parasitism; parturition; Pregnancy; Proteins; pups; Rats; Scarcity; small intestine; Strongylida Infections - immunology; Strongylida Infections - parasitology; Strongylida Infections - physiopathology; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Worms; Energy intake; Nematodes; Rats; Protein nutrition; Lactation; Endocrinopathy; Nutrition; Rat; Rodentia; Supply; Parasite; Parasitosis; Protein; Feeding; Infection; Target tissue resistance; Vertebrata; Mammalia; Energy; Animal
• ISSN: 0007-1145; 1475-2662
• DOI: 10.1017/S0007114511001565

Periparturient relaxation of immunity (PPRI) to parasites in mammals results in higher worm burden and worm egg excretion and may have a nutritional basis. Nippostrongylus brasiliensis re-infected lactating rats fed low-crude protein (CP) diets show an augmented degree of PPRI compared with their high CP-fed counterparts. However, such effects of CP scarcity have been confounded by metabolisable energy (ME) scarcity due to increased intake of the high-CP foods. Here, we independently assessed the effects of dietary CP and ME scarcity on the degree of PPRI. Second, parity rats were infected with N. brasiliensis larvae before mating. Upon parturition, dams were allocated to one of six feeding treatments (1–6), consisting of two levels of dietary ME supply, each with three levels of CP supply. On day 2 of lactation, dams were either re-infected with 1600 N. brasiliensis larvae or sham-infected with PBS, while litter size was standardised at ten pups. Dams and litters were weighed daily until either day 8 or 11 of lactation, when worm burdens were assessed as a proxy for PPRI. Increased CP and ME supply independently improved lactational performance. While ME supply did not affect parasitism, increasing CP supply reduced worm burden and the percentage of female worms in the small intestine; the latter was especially pronounced at the lower level of ME supply. The present results support the view that PPRI to parasites may be sensitive to CP scarcity, but not to moderate ME scarcity.