Effects of cholecystokinin on liquid diet intake of early weaned piglets.

The effect of cholecystokinin octapeptide (CCK-8) on the consumption of a liquid diet was investigated in 10 piglets, weaned on Day 1, housed individually in cages, and offered a commercial diet for suckling from feeding bottles nine times a day at 2-h intervals with an 8-h break during the night. CCK-8 was administered to piglets (n = 5) on Days 2, 4, 6, 8, 10, 12, 20, and 23 in single intraperitoneal doses of 4 microg x kg(-1) in saline, 5-7 min before the first morning feeding at 0600 h. The relative diet intake in CCK-treated animals was reduced significantly (p < 0.05) on Days 2, 4, 6, 8, 10, 12, and 23 compared to saline-treated controls, and on Days 2, 4, 6, 8, 10, 12, and 23 when the consumption at 0600 and 0800 h in CCK-treated piglets was compared. Our data support the notion that the short-term mechanisms involved in food intake control of piglets are relatively complex and operative at the time of birth, and that CCK plays a role in their food intake regulatory cascade.

[Changes in hydration in chicken and duck eggs during incubation]. / Zmeny hydratace slepicích a kachních vajec behem inkubace.

Water loss was determined during incubation in 80 eggs of the domestic fowl, White Leghorn-LB and New Hampshire-NH (between the 1st and 20th day), and in 80 eggs of Beijing White ducks (between the 1st and 25th day). Our data have shown that, the lowest actual water content was found in NH eggs, the highest in the duck eggs. Water content decreased absolutely and relatively during incubation; 365 in LB, 500 in NH and 312 mg/d in ducks. Water loss was higher in the first half of hatching. In the second half it was probably partly offset by water originating from fats oxidized for energetic purposes; the offset made a third in LB and NH, and still more in the ducks. Our results are somewhat different from the literature data, the variability of which is considered to be rather high in general. There were large shifts of water among the egg components during incubation. Water totally disappeared from the albumen, although it contained approximately three quarters of water was at the beginning of hatching. Already in the first half of incubation, more than a third of water was transported to the embryo, fetal membranes and fluids. In the subsequent ten days, water accumulation in the body of the developing and growing embryo was especially rapid; the water amount increased eight times in the fowl, seven times in the duck bodies. Water losses and its shifts show not only interspecific differences related to different lengths of incubation, but also intraspecific ones, between BL and NH.

The effects of diarrhoea on food intake in piglets weaned on the day of birth.

Large White x Landrace piglets (23 animals) weaned on the first day after birth were reared individually in a thermoneutral environment on a liquid diet having a macronutrient content similar to that of sow's milk. They were offered the diet from sucking bottles nine times a day at 2-h intervals. According to the appearance of the faeces the animals were divided into two groups: diarrhoeic piglets and clinically healthy animals. Their consumption of the diet, energy (GE) and macronutrients was assessed from the 3rd to the 10th day after birth; a total of 514 and 441 measurements were made in diarrhoeic piglets and healthy controls, respectively. With advancing age the intake of the diet by animals of the two groups changed in the same way as we described in previous studies. In diarrhoeic piglets, however, both the actual and the relative food intake, expressed in relation to live body mass and metabolic mass, was lower on days 3, 5 and 6 than in the healthy controls. In the period of the earlier described transient decrease in food consumption this difference disappeared and was observed again in piglets 9 (actual diet intake) and 10 (both actual and relative diet intake) days of age. Impairment of their enteral functions manifested by decreased ingestion of the liquid diet, GE, N substances and lipids was also observed after ontogenic shift of regulatory mechanisms of food intake control to a higher integrative level.

Effect of intraperitoneal administration of amino acids on the food intake of piglets on a liquid diet during the first month after birth.

The effect of single intraperitoneal 1 g.kg-1 doses of a solution of 20 amino acids (AA) on food intake was investigated in 20 piglets examined repeatedly between 2 and 26 days of age. The animals were reared individually from day 1 after birth in cages and bottle-fed a liquid diet nine times per day at two-hour intervals from 6 to 22 h. Although amino acid administration did not significantly affect plasma concentrations of total free AA throughout the experiment (as measured just before and 2 and 5 h after AA administration in blood withdrawn from the external jugular vein) it did produce a downward trend in food intake of piglets at 9-10 d of age. In older animals, the depressive effect on food intake was significantly greater and lasted longer. It is suggested that the aminostatic component of food intake regulation in piglets does not begin to operate until the weaning period.