1. Sepsis was induced in rats by an intravenous injection of live bacteria. Infected and pair-fed animals were studied before the infection, in an acute septic phase (day 2 post-infection), in a chronic septic phase (day 6) and in a late septic phase (day 10). Protein synthesis rates were measured in vivo after administration of a flooding dose of L[1-13C]valine. 2. During the acute phase, muscle protein loss associated with infection resulted from both a decrease in protein synthesis and an increase in proteolysis. During the chronic phase and the late phase, the increase of proteolysis in infected rats as compared with pair-fed animals persisted, worsening muscle atrophy. Skin protein synthesis rates were not significantly modified by infection. However, skin protein content decreased 6 and 10 days after infection, suggesting an increased proteolysis in response to sepsis. 3. Protein synthesis in liver of infected rats was twice that of pair-fed animals. Liver protein synthesis remained elevated in infected rats compared with pair-fed animals until day 10. Hypoalbuminaemia and high plasma concentrations of fibrinogen were evident at all periods studied. alpha 2-Macroglobulin and alpha 1-acid glycoprotein reached peak concentrations during the acute phase (concentrations increased 50 times in infected rats). On day 10, the levels of these proteins were still about 12-fold higher. 4. Protein synthesis rates were significantly increased in the digestive tract and lung of infected rats compared with pair-fed groups on days 2 and 6, but were similar in the two groups on day 10 post-infection. The fractional protein synthesis rate was increased 3-fold over the entire experimental period in the spleen. 5. The results show that sepsis stimulates protein synthesis in various tissues over a long time, and that skin, like muscle, can provide amino acids to the rest of the body.

Colostrum and milk samples from 60 Holstein–Friesian cows were analysed for concentrations and yields of immunoglobulin G (IgG), β-lactoglobulin (β-lg), α-lactalbumin (α-la) and serum albumin (BSA) throughout the first 16 milkings post partum (8 d of lactation) using a single radial immunodiffusion assay. Concentrations (mg/ml, means±SD) at first milking were IgG 59·8±28·5, β-lg 14·3±4·6, α-la 2·04±0·6, BSA 1·21±0·44. Large variations were recorded for IgG concentrations (15·3–176·2 mg/ml) and yields (0·2–925 g). Cows in their first lactation produced significantly lower concentrations and yields of colostral IgG than cows in later lactations. A colostral yield of IgG below the 100 g required to prevent calf hypo-γ-globulinaemia was found in 18·3% of the cows. The concentrations of IgG, β-lg and BSA dropped abruptly in subsequent milkings and α-la concentration decreased slowly. The mean IgG concentration was <2 mg/ml after eight milkings and <1 mg/ml after fifteen milkings. However, IgG concentration did not differ significantly, at the 1% level, during milkings 11–15. The results were tabulated to make it possible to calculate the excess of whey proteins that would be obtained if early milks were illegally added to the milk supply.

Lactoferrin (Lf) and IgG were estimated in camel's milk from Kazakhstan, where 2 species of camels (Camelus bactrianus, Camelus dromedarius) and their hybrids cohabit. The concentrations of Lf and IgG were determined according to 3 variation factors: region (n = 4), season (n = 4), and species (n = 5; sample 4 was mixed milk and sample 5 was of unknown origin). The mean values in raw camel's milk were 0.229 +/- 0.135 mg/mL for Lf concentration and 0.718 +/- 0.330 mg/mL for IgG concentration. The seasonal effect was the only significant variation factor observed, with the highest values in the spring for Lf and in the winter for IgG. The Lf concentration varied in 1-wk postpartum milk from 1.422 to 0.586 mg/mL. The range in IgG concentration was wide and decreased from 132 to 4.75 mg/mL throughout the 7 d postpartum, with an important drop after parturition. In fermented milk, the lactoproteins are generally hydrolyzed. For milk samples from undefined species, discriminant analyses did not allow the origin of the species to be determined. A slight correlation between Lf and IgG concentrations was observed in raw milk. The values were slightly higher than those reported in cow's milk, but this difference was insufficient to attribute medicinal virtues to camel's milk.

-The effect of temporary once-daily milking, starting right after calving, on milk production and nutritional status of 50 Holstein cows (15 primiparous) was studied. Primiparous cows were divided into two groups: a control group (Pc) continuously milked twice daily and an experimental group (P3) milked once a day for the first three weeks of lactation and then twice daily. Multiparous cows were divided into three groups: a control group (Mc) continuously milked twice daily, an experimental group milked once a day for the first three weeks of lactation and then twice daily (group M3), and another experimental group milked once a day for the first six weeks after calving and then twice daily (group M6). The trial ended when the cows were turned out to pasture. Cows milked once daily did not seem to suffer from discomfort. Once-daily milking decreased the milk yield by 2.7 kg.d-I (P < 0.10) in week I of lactation, by 8.4 kg.d-I (P < 0.01 ) in week 3 and by 14.5 kg.d-I (P < 0.01 ) in week 6. The effect of once-daily milking was not different between primiparous and multiparous cows. During the first week of twice-daily milking, the milk yield of experimental groups increased by 6.8 8 kg.d!' (a non significant difference between P3, M3 and M6 groups). From week 7 onwards, the milk yield of the P3 and M3 groups was lower than the milk yield of the Pc and Mc groups by 2.4 kg.d-I (P < 0.10), and the milk yield of the M6 group was lower than the milk yield of the Me group by 5.4 kg-d-I (P < 0.01 The protein content of milk was higher in experimental groups than in control groups by 2.4 g.kg-' during both experimental and post-experimental periods. Somatic cell counts in milk were not significantly different between the groups. Cows milked once a day lost less body condition and live weight in early lactation than control cows, and their energy balance was less negative or more positive (the difference was significant for the M6 group). (lot M6). L'essai s'est terminé à la fin de la période hivernale. La traite une fois par jour n'a pas semblé provoquer d'inconfort chez les vaches. Elle a diminué la production laitière de 2,7 kg-j-1 en 1 re semaine de lactation, de 8,4 kg-j-1 en 3' semaine, et de 14,5 kg!jw en 6 e semaine. Son effet n'a pas été différent entre les vaches primipares et multipares (p > 10 %). Dès la première semaine de traite deux fois-j-1 , la production laitière des vaches expérimentales a augmenté de

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