First description of milk flow traits in Tunisian dairy dromedary camels under an intensive farming system

Abstract

In order to evaluate milking ability in dromedary camels, 124 milk flow curves were registered during morning milking of 20 dairy Maghrebi dromedary camels. Animals were in lactations 1-8, were 6-19 years old and were 4-15 months of their current lactation. Milk flow curves were recorded using an electronic milk flow meter (Lactocorder®). Milk flow curves were classified in three typical patterns: type 1 represents curves with one high and short peak of milk flow; type 2 represents curves with a moderate mean milk flow rate during a large plateau phase; and type 3 represents curves with lower mean milk flow rate and a relatively longer milking duration. The ratio of the different milk flow patterns in the population evaluated was 40:38:22% for types 1, 2 and 3, respectively. The highest milk yield per milking, average and peak milk flow were observed in camels with type 1 curves (4·24 kg, 1·49 and 3·54 kg/min, respectively) followed by type 2 animals (3·30 kg, 1·12 and 2·12 kg/min, respectively) and lastly type 3 curves (2·34 kg, 0·65 and 1·23 kg/min, respectively). This study confirmed that a major proportion of dromedary camels have a suitable machine milking ability. Nevertheless, our results suggest that pre-stimulation and improving the milking process may improve milking efficiency and guarantee a more complete and rapid emptying of the udder.

Physiology of lactation and machine milking in dromedary she-camel

“…The amount of cisternal milk decreases in late stage of lactation compared with early and middle stage of lactation (Atigui et al, 2014a).…”

“…cortisol level was already elevated and remained high (47.1±7.8 ng/ml) during milking and slowly decreased after milk removal ceased (Atigui et al, 2014a).…”

“…However, unusual sound at the beginning of milking or even after milk ejection occurrence caused inhibition or disruption of milk removal and modification of camel's behaviours (Atigui, et al, 2014b). In one study, it was observed that the basal concentration of cortisol remained low during milking (9.6±2.8 ng/ml) in normal conditions (Atigui et al, 2014a).…”

“…Depending on whether and how long a pre-stimulation is performed prior to the actual removal of the milk, there is a temporary break of the milk flow curve (bimodality), when the cistern milk is removed before the first alveolar milk was pressed into the cistern. Atigui et al (2014a) reported that in camels, bimodal curves occurred in 41.9% of total recorded milk flow curves. Such higher percentage bimodality in camels could be explained, that since camels have very small cisterns and a delayed milk ejection reflex, bimodality occurs when the vacuum level provided by machine milking is able to open the teat sphincter and empty the cistern before the milk ejection takes place.…”

“…only a small cisternal fraction of milk (4-10%) is available (Juhasz & Nagy, 2008;Caja et al, 2011;Atigui et al, 2014a;Ayadi et al 2016) and the alveolar fraction of milk is large (90-95%) (Caja et al, 2011). The amount of cisternal milk decreases in late stage of lactation compared with early and middle stage of lactation (Atigui et al, 2014a).…”