Joanna Bogucka

Influence of Different Stages of Experimental Chronic Kidney Disease on Rats Locomotor and Postural Skeletal Muscles Microcirculation

Background. Chronic kidney disease (CKD) is associated with muscle excess fatigue and diminished maximal whole body oxygen consumption, which in part could be depended on poor muscle microcirculatory network. The aim of this study was to assume the influence of different stages of CKD on microcirculation vessels in functionally different skeletal muscles—locomotor, the gastrocnemius muscle, and postural, the longissimus thoracis muscle. Methods. Male Wistar rats underwent sham operation (CON), uninephrectomy (CKD 1/2) and subtotal nephrectomy (CKD 5/6). Muscle samples were stained for an alkaline phosphatase to differentiate capillaries. The number of capillaries was estimated by a single observer in 10 μm transverse sections by point counting at a magnification of ×125 using an Image Analysis System Q 500 MC of Leica. Blood pressure and serum creatinine, haptoglobin, MCP-1, VEGF, and PDGF were measured. Results. There were significant differences (p < 0.05) in CD (number of capillaries per 1 mm2 of muscle tissue), C:F (capillary to fiber ratio), and CC/F (capillary contact per fiber). The CKD 1/2 group in gastrocnemius and longissimus muscle had 53% and 33% lower C:F; 56% and 33% lower CD; and 44% and 20% less CC/F than CON, respectively. The CKD 5/6 group in gastrocnemius and longissimus muscle had 46% and 20% lower C:F; 47% and 11% lower CD; and 48% and 25% less CC/F versus control, respectively. Blood pressure was higher in CKD 5/6 vs. CKD 1/2 and CON (145/95 vs. 107/87 and 119/77 mmHg, p < 0.05, respectively). CKD 5/6 had higher creatinine than CKD 1/2 and CON (1.22 vs. 0.83 and 0.74 mg/dL, p < 0.05, respectively). Haptoglobin was higher in CKD 1/2 and CKD 5/6 versus CON (1.68 and 1.63 vs. 0.70 mg/mL, p < 0.05, respectively). MCP-1 was higher in CKD 5/6 and CKD 1/2 versus CON (609 and 489 vs. 292 pg/mL, p < 0.05, respectively). There were no significant differences in serum growth factors concentration between groups. Conclusion. Capillary rarefaction is present in early stages of CKD. These changes are independent of blood pressure and progression of CKD. We suspected that muscle function has a big impact on microvasculature as capillaries rarefaction has been reduced more in locomotor than postural skeletal muscle.

Profile of fatty acids, muscle structure and shear force of musculus longissimus dorsi (MLD) in growing pigs as affected by energy and protein or protein restriction followed by realimentation

Forty-eight gilts were submitted to a 30% restriction of feed (groups F and F1) or protein intake (group P) from 90 to 118 days of age, followed by realimentation from 119 to 168 days of age. Control pigs (C) were fed during the whole experiment according to a semi ad libitum scale. During realimentation all animals were fed according to semi ad libitum scale except pigs F1 which were fed ad libitum. Six pigs from each group were slaughtered at the end of restriction and realimentation. Restriction decreased the weight of musculus longissimus dorsi (MLD) and increased shear force. Restriction of feed intake depressed MUFA concentration and increased n-6/n-3 ratio while protein restriction decreased n-6/n-3 and PUFA:SFA ratios. Structure of fibers was not affected. After realimentation MLD mass was still lower in all previously restricted pigs, shear force was the lowest in F1 pigs. Only percentage of fast twich oxidative fibers was significantly greater in F1 pigs than in others. Significant correlations between parameters investigated during the study were found.

Microstructure of longissimus lumborum Muscle in Pigs of several Breeds and Its Relation to Meat Quality Traits

A total of 190 animals, representing Polish Landrace, Pietrain, Z³otniki Spotted pigs and Pietrain (Polish Large White Polish Landrace) crosses were investigated. Samples of longissimus lumborum muscle were taken for histological tests and frozen in liquid nitrogen. After microscopic preparations were made, they were subjected to histochemical reactions to identify muscle fibre types differing in metabolism, and to determine the percentage of intramuscular fat and glycogen in the analysed muscle. The analysis of longissimus lumborum structure showed that Pietrain pigs had the largest proportion of FTG fibres and the smallest proportion of STO fibres that are the most beneficial in terms of meat quality characteristics. The greatest diameters of all muscle fibre types were in the muscle of Pietrain (Polish Large White Polish Landrace) crosses, which were also found to contain the lowest number of fibres in the muscle cross-section area. The least favourable meat quality traits were shown by Pietrain pigs. Their meat was characterized by considerable acidification 45 minutes postmortem, lightest colour and the least favourable water holding capacity.

Performance and small intestine morphology and ultrastructure of male broilers injected in ovo with bioactive substances

Abstract The objective of the present study was to determine the effect of prebiotic and synbiotic preparations injected in ovo on day 12 of embryogenesis on both development of intestinal villi and the number of neutral goblet cells in the small intestine of male broiler chickens on day 35 of rearing. Eggs containing live embryos were randomly separated into five experimental groups (1800 eggs per group), and treated with different bioactive compounds by in ovo injection. The control group (C) was injected with physiological saline. The prebiotic groups (PI and PB) were injected with a solution containing 1.76 mg of inulin or with a solution containing 0.528 mg of Bi2tos. The injection solution for both synbiotic groups (SI and SB) consisted of 1.76 mg Inulin + 1000 CFU of L. lactis spp. lactis 2955 (SL1) or 0.528 mg Bi2tos + 1000 CFU of L. lactis spp. cremoris 477 (SC1). Samples for histological analysis were taken from the three segments of the small intestine: the duodenum, jejunum and ileum. Broiler performance increased in the prebiotic group injected with Bi2tos when compared to both the control group and the prebiotic group injected with inulin. In relation to other groups, in the duodenum and ileum the highest intestinal villi were observed in chickens with the lowest body weight, i.e. groups C and PI. The smaller surface area of villi was found in the jejunum and ileum in group SB. As far as the jejunum and ileum are concerned, a significantly higher number of goblet cells was noted in groups PB and SB.

Microstructure of Longissimus Lumborum Muscle and Meat Quality of Native Polish Pig Breeds: Złotnicka Sp Otted and Puławska

Abstract In 50 fattening pigs representing two Polish native breeds: 24 Złotnicka Spotted, 10 Puławska and 16 F1 ♀ (Polish Large White × Polish Landrace) × F1 ♂ (Duroc × Pietrain) crosses microstructure of muscle, carcass and meat quality were studied. Puławska pigs had the thickest backfat, but the loin eye area was smaller only in comparison to crossbreds. Compared to the Puławska breed, the meat of Złotnicka Spotted pigs was darker, which was associated with a greater percentage of type I fibres and a smaller percentage of type IIB fibres. Puławska pigs distinguished themselves from the other groups under study by the greatest density of fibres per mm2. Smaller diameter of type IIA and IIB fibres and higher total number of fibres were found in Puławska breed pigs compared to Złotnicka Spotted, despite the absence of differences in the loin eye area. Smaller thickness of the fibres favourably affects meat quality, and might be considered an indicator of a delicate structure of meat.