Effect of pregnancy and embryonic mortality on milk production in dromedary camels (Camelus dromedarius)

Abstract

The main objective of the present study was to compare milk production in pregnant versus nonpregnant dromedary camels. In addition, we described the effect of embryonic mortality on lactation and measured serum progesterone levels until d 60 to 90 of gestation. Twenty-five multiparous camels were selected in midlactation for 2 studies in consecutive years. Camels were mated naturally when the size of the dominant follicle reached 1.2 to 1.5cm. Pregnancy was diagnosed by ultrasonography and progesterone determination. In the first experiment (Exp 1), 8 of 11 animals conceived at 284±21.5d postpartum. Three pregnant dromedaries were given PGF2α to induce luteolysis and pregnancy loss on d 62 and spontaneous embryonic loss was detected in 2 camels (on d 27 and 60). Animals were allotted to 3 groups retrospectively: nonpregnant camels (group 1, n=4), pregnant camels (group 2; n=3), and camels with embryonic loss after d 55 (group 3; n=4). In the second study (Exp 2), 14 dromedaries were mated during midlactation. Seven of them failed to conceive (group 1) and 7 became pregnant (group 2). No embryonic loss was detected in Exp 2. Turning points in milk production were identified by change point analysis. In nonpregnant dromedaries (group 1), milk decreased slowly over time without significant change point. In pregnant camels (group 2), a gradual decline until 4 wk after mating was followed by a sudden drop, and the change point model resulted in one breakpoint at d 28±7 and 35±3 of gestation in Exp 1 and Exp 2, respectively. In camels with embryonic mortality (group 3, Exp 1), milk yield started to decline similarly as in pregnant animals, but milk production increased gradually after embryonic loss and reached similar levels as in their nonpregnant herdmates. Change point analysis for group 3 resulted in 2 turning points at 30±4 and 48±4d after conception. Mean length of lactation was shorter by 230 (34.2%) and by 249d (37.6%) and mean total lactation production was decreased by 1,532 (31.6%) and 2,151 kg (44.3%) in pregnant compared with nonpregnant camels in Exp 1 and Exp 2, respectively. We concluded that the calving interval can be shortened by mating during midlactation. However, pregnancy has a strong negative effect on milk production as dromedaries stop lactating by the fourth month of gestation. Following embryonic mortality within 3mo of conception, milk production is restored.

Milk yield and modeling of lactation curves of Tnisian she-camel

“…Little correlation was observed between milk quantity and lactation stage. An important lactation-gestation recovery period was observed (283 +/-93 day) which can have an effect on the lactation length as described recently by Nagy et al (2014). Correlation coefficient between persistency indices and total day milk yield was indicated a good persistency value calculated for this breed.…”

A systemic review on ultrasonographic applications in camels

“…Regarding uterine pathologies, ultrasound has been used for diagnosis of various reproductive disorders such as; early embryonic death, endometritis, vaginal adhesions, ovarian cysts, ovarian hydrobursitis and during treatment with intrauterine therapies (Tibary and Anouassi, 2001;Ali et al, 2010a&b;Nagy et al, 2015 andAli et al, 2015b). Ultrasonographically, ovarian hydrobursitis, is characterised by a collection of anechoic fluid within the ovarian bursa and hyperechoic encapsulation of the ovary (Tibary and Anouassi, 2001).…”

“…Ultrasonography is used extensively as a safe and non-invasive diagnostic technique in veterinary medicine (Fouad et al, 2000;Elnahas, 2008;Mostafa et al, 2014a;Abu-Seida et al, 2015) and as a method of choice for detecting reproductive disorders in large domestic animal species (Ali et al, 2013;Nagy et al, 2015). It is ideal for dairy production because it does not emit radiation that can be harmful to the pregnant herd and does not require anti-radiation shields, vests and building which can cause additional farm expenses.…”

Commerce en ligne du lait de chamelle : nouveaux acteurs, nouveaux marchés

“…Cependant, si le potentiel de production de la chamelle peut être aisément comparé à celui des zébus élevés en zone tropicale, il apparait plus faible par rapport aux vaches laitières sélectionnées, en raison d'un cycle de reproduction deux fois plus long, de l'inadaptation des machines à traire utilisées en élevage bovin, et des besoins alimentaires plus spécifiques (Nagy et al, 2015 ;Ayadi et al, 2018 ;Faye, 2016). De ce fait, les coûts de production du lait de chamelle en fermes intensives sont élevés et le résultat économique d'une ferme cameline intensive ne peut être bénéfique qu'avec un prix de vente du lait lui aussi élevé.…”