ABSTRACT
The main objective of this study is to determine the impact of the camel livestock system on individual and herd performances of milk production, lactation curve, fats, and protein concentrations. For this purpose, 13 she-camels of Sahraoui breed from the south eastern Algeria and belonging and semi-intensive system (N = 6) and intensive system (N = 7) were studied. Recording and sampling of milk were carried out at regular intervals during a full lactation. The lactation curve was estimated using Wood's gamma function and the t-test of independent groups was carried out to compare lactation performances, lactation curve, and reproductive parameters. The overall average daily milk (DMY), fat (DFY), and protein (DPY) yield were 6.77 ± 0.82 kg/day, 4.15 ± 0.91%, and 4.49 ± 0.20%, respectively. The mean of total milk yield (TMY) was 2696.39 ± 343.86 kg during a mean lactation length (LL) of 398.38 ± 20.65 days. The peak of milk production (6.79 ± 0.68 kg) was reached at 93.9 ± 55.8 days after calving. The open day (DO) and inter-calving interval (ICI) recorded in this study were 348.38 ± 30.33 and 723.38 ± 30.33 days, respectively. There is no significant difference (p > 0.05) between intensive and semi-intensive breeding systems for TMY (2795.39 ± 261.88 kg vs. 2580.89 ± 414.43 kg), DMY (6.96 ± 0.66 kg vs. 6.55 ± 1.00 kg), and LL (402.14 ± 21.18 days vs. 394 ± 21.03 days). However, the total amount of fat was significantly higher in intensive system (182.02 ± 33.91 kg) and the DPY content was significantly higher in semi-intensive system (4.60 ± 0.13%). The parameters α, ß, and γ of lactation, fat, and protein curves between the two systems showed a highly significant difference (p < 0.01) for the parameters (α and ß) for the milk production curve, significant (p < 0.05) for the time to reach peak yield, and no significance for the other parameters. The corresponding values of the coefficient of determination (R2) were 0.62, 0.35 for milk yield (p > 0.05), 0.12, 0.13 (p > 0.05) for fat, and 0.03, 0.11 (p < 0.05) for protein, in the intensive and semi-intensive systems, respectively. In addition, DO and ICI were not significantly different between the livestock systems, but were higher in the intensive system than the semi-intensive system (337.17 ± 26.26 vs. 712.17 ± 26.26, respectively). The study concluded that the intensive system had a higher milk performance with a more efficient lactation curve. The incomplete gamma model (Wood) used in this study was inappropriate for estimating milk yield, but acceptable for fat and protein.
Subject(s)
Camelus , Lactation , Female , Animals , Reproduction , Milk , Africa, Northern , LivestockABSTRACT
Camels are considered an important food source in North Africa. Trypanosomiasis in camels is a life-threatening disease that causes severe economic losses in milk and meat production. Therefore, the objective of this study was to determine the trypanosome genotypes in the North African region. Trypanosome infection rates were determined by microscopic examination of blood smears and polymerase chain reaction (PCR). In addition, total antioxidant capacity (TAC), lipid peroxides (MDA), reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) were determined in erythrocyte lysate. Furthermore, 18S amplicon sequencing was used to barcode and characterizes the genetic diversity of trypanosome genotypes in camel blood. In addition to Trypanosoma, Babesia and Thelieria were also detected in the blood samples. PCR showed that the trypanosome infection rate was higher in Algerian samples (25.7%) than in Egyptian samples (7.2%). Parameters such as MDA, GSH, SOD and CAT had significantly increased in camels infected with trypanosomes compared to uninfected control animals, while TAC level was not significantly changed. The results of relative amplicon abundance showed that the range of trypanosome infection was higher in Egypt than in Algeria. Moreover, phylogenetic analysis showed that the Trypanosoma sequences of Egyptian and Algerian camels are related to Trypanosoma evansi. Unexpectedly, diversity within T. evansi was higher in Egyptian camels than in Algerian camels. We present here the first molecular report providing a picture of trypanosomiasis in camels, covering wide geographical areas in Egypt and Algeria.
