Impact du réglage de la machine à traire sur la santé mammaire et qualité du lait chez la vache laitière

M. ATIGUI¹

L. BEN HAJSAID¹

G. BEN FRAJ¹

R. YAHYA²

M. KAMOUN¹

¹ Laboratoire d'Amélioration et de Développement Intégré de la Productivité Animale et des Ressources Alimentaires, Ecole Supérieure d'Agriculture de Mateur, Route tabarka_7030, Université de Carthage, Tunisie

² Office d’élevage et de pâturage, Rue Mongi Slim Nabeul, 8000.

Abstract - This work was carried out to evaluate machine milking routine and settings in smallholder dairy cow’s farms and to assess the impact of optimizing machine settings on milk quality and udder health. A total of 39 dairy farms in Nabeul governorate northeast of Tunisia, were included in this study. Only farms that were not subjected to any official or nonofficial dairy control program and not receiving any technical assistance were considered. During 2 visits before machine setting and 2 visits after, 484 milk samples from 121 Holstein cows were collected. Results showed that 38% of the visited farms had used and defected machines, 55% of the teatcup’s rubbers were used and cracked. More than 53% of the farmers used vacuum level higher than 48 kPa and less than 44% of them used the recommended pulsation frequency. Only 15% of the diagnosed machines had operational manometers and showed the real vacuum level. After resetting the milking machines milk quality changed greatly. Milk fat increased significantly 2.86 ± 0.93 % to 3.29 ± 0.98 % while protein content decreased 3.02 ± 0.4 % to2.87 ± 0.33 %respectively before and after machine setting. Individual Somatic Cell Count decreased significantly from 776.45 10³ Cell/ml to 416.81 10³ cell/ml after milking settings adjustment. This study showed the importance of technical assistance of smallholders’ dairy farmers to achieve the goal of better milk quality and udder health. 

Keywords: Vacuum, Pulsation, Somatic Cell Count, Smallholder farms, Dairy Cow.

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AZZA RHAIEM*^{1 2}

¹ Laboratory of Microorganisms, National Gene Bank (Banque Nationale de Gènes), Boulevard of the leader Yasser Arafat, ZI Charguia-1, 1080 Tunis, Tunisia;

² University of Carthage, Institut National de la Recherche Agronomique de Tunisie (INRAT), Laboratory of Plant Protection (LR11INRAT04), Rue Hédi Karray, 1004, Menzah 1, Tunis, Tunisia

Abstract - Seventy-eight bacteria belonging to the genus Bacillus, isolated from salty soils in Tunisia, were assessed for their antagonistic activity against Ascochyta rabiei, the causal agent of Ascochyta blight of chickpea. Effect of treatments with the different bacteria on disease severity and plant growth parameters was evaluated under greenhouse conditions. Based on Mass Disease Index (MDI), tested bacteria were classified into four groups. Bacteria of the first group were able to significantly reduce disease severity as compared to the control inoculated by A. rabiei, and showed relatively better efficiency than fungicides included in the assay. Results revealed that the different treatments had a significant effect on disease development and plant growth parameters, particularly on plant length and plant weight. Based on disease and growth parameters, 38 bacteria of the genus Bacillus among 78 could be selected from this experiment, of which one strain of B. sphaericus, two strains of B. cereus, four strains of B. thuringiensis and thirty-one strains of Bacillus spp. The efficiency of the 11 selected bacteria belonging to the first group was confirmed by reassessing their antagonistic activity under greenhouse and field conditions. In vitro testing was also performed.

Keywords: Bacillus, Ascochyta blight, Mass Disease Index, antagonistic activity

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AZZA RHAIEM^{1 2}

¹Laboratory of Microorganisms, National Gene Bank (Banque Nationale de Gènes), Boulevard of the leader Yasser Arafat, ZI Charguia-1, 1080 Tunis, Tunisia; e-mail:

² University of Carthage, Institut National de la Recherche Agronomique de Tunisie (INRAT), Laboratory of Plant Protection (LR11INRAT04), Rue Hédi Karray, Menzah 1, 1004 Tunis, Tunisia

Abstract - Pathogenicity of 20 isolates of Botrytis sp., 15 of which were isolated from different locations in Tunisia, was studied based on the reaction of five Vicia faba genotypes with known differential reaction to the disease. ANOVA of the chocolate spot disease infection over time revealed highly significant (p=0.001) differences among isolates and isolatesgenotypes interaction. These differences were observed in greenhouse experiment using whole potted plants as well as in vitro assay using detached leaves. The twenty tested isolates were classified into 6 virulence groups based on genotypes reaction under greenhouse conditions. While the tested genotypes of Vicia faba reacted differently to B. fabae isolates, with results ranging from high susceptibility to moderate resistance, they have demonstrated a high resistance to all isolates of B. cinerea confirming the idea stating that this species is not important in disease development. Significant correlations were obtained between disease assessment under greenhouse conditions and vitro testing when a discriminating scale was used for detached leaves. However, the relationship between the two evaluation methods is likely to be not obvious and a combination of different methods should probably be adopted in order to have accurate estimation of the pathogenicity.

Keywords: Chocolate spot, Faba bean, Botrytis fabae, B. cinerea, pathogenicity

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S TORCHE¹

S BOUSSENA²

K BEROUAL¹

B M GUIDOUM³

M KERROUR⁴

N MOULA⁵

¹Pharmacology and Toxicology University Research Laboratory, Institute of Veterinary Sciences, University of Frères Mentouri, Constantine, Algeria.

²Management of Animal’s Health and Productions Laboratory, Institute of Veterinary Science, University of Frères Mentouri, Constantine, Algeria.

³ Veterinary expert and practitioner, Constantine, Algeria.

⁴ Institute of Veterinary Science, University of Frères Mentouri, Constantine, Algeria.

⁵Department of Animal Production, Faculty of Veterinary Medicine, University of Liège, Belgium.

Abstract - The aims of the current study were to characterize the main clinical consequences of diarrhea and to identify metabolic disorders due to this neonatal disease in newborn calves (≤30 days of age). Forty seven calves of two selected dairy herds in the province of Constantine were involved in this study. Clinical examination and analysis of blood samples collected from untreated calves over 3 periods (birth to 7 days, 8 to 15 days and over 15 days) were carried out from February to October 2013. Hematological (Hemoglobin (HGB) and Hematocrit (HCT)), biochemical (Sodium (Na⁺), Potassium (K⁺), Chloride (Cl^-) and pH) and organic parameters (Total protein, Glucose, Urea and Creatinine) were analyzed at the onset of diarrhea, before any treatment in diarrheic calves and subsequently compared with the values obtained in clinically healthy calves and standards reported in the literature. Base excess (BE) and the strong ions difference (SID) were also calculated by the previous assays. Results of this study showed that respiratory rate was significantly higher in calves with diarrhea (P<0.05). The occurrence of a minimal insignificant metabolic disturbance (P>0.05) was observed in diarrheic calves. A significant increase in total protein, and an insignificant difference for the rest of the analyzed hematological and biochemical parameters in diarrheic calves were observed at the statistical level P<0.05 during the experiment. A negative energy balance reflected by hypoglycemia (107.2±2.5 mg/dL in diarrheic calves versus 121.8±4.6 mg/dL in healthy calves) was also noted during the diarrheal syndrome (P>0.05).

Keywords: acidosis, dehydration, neonatal diarrhea, total protein, Algeria.

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