Sakly C.,Institute Superieur Agronomique Of Chott Meriem |
Rekik M.,Ecole Nationale de Medecine Veterinaire |
Ben Salem I.,Ecole Nationale de Medecine Veterinaire |
Lassoued N.,French National Institute for Agricultural Research |
Ben Salem H.,French National Institute for Agricultural Research
Journal of Animal Physiology and Animal Nutrition | Year: 2014
Reproductive outputs in fat-tailed Barbarine sheep in central Tunisia are often low because of feed shortage and the low nutritive value of diets. Supplementation with conventional concentrates is economically unsuitable in central Tunisia, so more cost-effective and sustainable alternative feeding strategies need to be developed. We tested effects of short-term nutritional treatments including cactus cladodes during the induction of 'male effect' on fertility and prolificacy parameters (follicular growth, ovulatory response and early embryo losses). One hundred and twenty ewes were distributed in 4 equal groups balanced for live weight grazed natural pastures and were supplemented for 21 days, starting day 10 after introduction of rams, with cactus cladodes (CA), cactus cladodes and soybean meal (CAS), concentrate (CC) or only soybean meal (S). Nutritional treatment did not affect live weight in this experiment. Ewes receiving cactus had higher number of large pre-ovulatory follicles (≥6 mm; 1.08 ± 0.05), between days 14 and 19 after introduction of rams, than females in the CC and S ewes (0.64 ± 0.06; p < 0.05). However, there were no differences in the onset of oestrous behaviour in response to 'male effect' or in the number of corpora lutea. Average ovulation rates were 1.42 ± 0.16 for CC, 1.47 ± 0.13 for CAS, 1.31 ± 0.15 for CA and 1.31 ± 0.13 for S groups respectively. Finally, reproductive wastages at day 35 after mating were not different between groups being 0.33 ± 0.19 for CC, 0.60 ± 0.17 for CAS, 0.43 ± 0.16 for CA and 0.31 ± 0.15 for S groups respectively. It is concluded that Barbarine ewes fed nutritional treatments including cactus performed similarly to those receiving diets including conventional concentrate feeds. © 2013 Blackwell Verlag GmbH.
Cossani C.M.,University of Lleida |
Thabet C.,Institute Superieur Agronomique Of Chott Meriem |
Mellouli H.J.,INRAT National Agricultural Research Institute of Tunisia |
Slafer G.A.,University of Lleida |
Slafer G.A.,Catalan Institution for Research and Advanced Studies
Experimental Agriculture | Year: 2011
Rainfed wheat is frequently exposed to periods of water stress that generate low and variable grain yields. Field experiments (with studies in Tunisia and Morocco) carried out in the context of a European research project of co-operation with Mediterranean partner countries (WatNitMED) showed that nitrogen (N) fertilization may be a tool to increase productivity of rainfed wheat in Mediterranean environments. However, most farmers in Northern Africa do not fertilize their rainfed cereals. In the present study, we aimed to analyse whether the generally accepted positive yield response to N fertilization in rainfed Mediterranean conditions corresponds to actual advantages achieved in the fields of working farmers, attempting a further up-scaling of knowledge from field experiments to real fields. We attempted to apply research results to Tunisian working farmers' fields by conducting a farm pilot experiment. The pilot experiment was conducted in two different regions (a low-yielding region and a relatively high-yielding region) of cereal production in Tunisia, where wheat production represents typical rainfed Mediterranean agro-ecosystems in North Africa. First, we compared the yield response to N fertilization against unfertilized conditions (a common situation for many of the farmers in North Africa), and secondly we compared what the farmers suggested as an optimal N fertilization practice in their fields against the WatNitMED's recommendation which was based on an N-fertilization scheme derived from field experiments from the European research project in Mediterranean conditions. The WatNitMED fertilization scheme suggested higher rates of fertilization than those considered optimal by farmers (on average 40 kg N ha?1 higher). Unfertilized grain yield across both locations ranged from about 1 to 3.5 Mg ha?1 (typical of farmers' yields in the region), and fertilizing increased grain yields in most situations. Within the two alternative fertilization treatments, WatNitMED fertilization produced higher yields than the fertilization rate considered optimal by farmers. This trend was observed at the low-yielding location as well as at the high-yielding location. These responses demonstrated that fertilization in working farmers' field conditions may be a reliable means of improving dryland wheat grain and straw yields. They also showed that rates of fertilization regarded as optimal by real farmers were below the optimum for these regions. © Cambridge University Press 2011.
Maamouri O.,French National Institute for Agricultural Research |
Atti N.,French National Institute for Agricultural Research |
Mahouachi M.,Ecole Superieure dAgriculture de Kef |
Kraeim K.,Institute Superieur Agronomique Of Chott Meriem
EAAP Scientific Series | Year: 2011
Tunisian dairy sheep is localized in sub humid area characterized by a high forage production and prairie growing. Nevertheless, young grass is characterized by a high level of soluble nitrogen which generates an important loss of urinary nitrogen leading to environment pollution. The objective of this work is to study the natural protection of protein by acacia tannins and its effect on urinary losses and milk production. An experimental sheep flock conducted on ray-grass grazing was divided into three homogeneous groups according to lactation rank. The first group (Control, C) received 300 g of concentrate, the second group (C-A) 300 g of concentrate and 100 g acacia, the last group only 100 g acacia (A). The nitrogen balance was realized on individual boxes with a daily cut herb. The dairy control was twice a month. Total milk production was higher for C-A group than for other groups, 48, 45 and 42 l for C-A, C and A respectively. Nitrogen intake varied significantly according to the concentrate and/or acacia supply. The average values were 22, 20 and 15 g/day for C-A, C and A group respectively. Urinary nitrogen excretion decreased from 6.5 g/d for C group to 4.5 g/d for C-A one, consequently to acacia intake. Conversely, the nitrogen retention significantly increased with acacia intake from 6 for C group to 10 g/d for C-A one. In conclusion, the acacia supply is a valid way to increase nitrogen retention and to manage the loss of nitrogen and environment.
Rekik M.,Ecole Nationale de Medecine Veterinaire |
Ben Salem I.,Ecole Nationale de Medecine Veterinaire |
Ben Hamouda M.,Institution Of La Recherche Et Of Lenseignement Superieur Agricoles |
Aloulou R.,Institute Superieur Agronomique Of Chott Meriem |
Ben Sassi M.,Office de lElevage et des Paturages
Livestock Research for Rural Development | Year: 2011
This study investigated the sources of variation and the genetic profile of the spring fertility of 18 months old Barbarine maiden ewes. The trait was coded as 1 or 0 for maiden ewes that did, or did not, lamb in fall, respectively. Data were 3314 maiden ewe records daughters of 408 sires taken over 12 consecutive years and 9 flocks kept at the pilot sheep farm of Jebibina and Saouaf in semi arid Tunisia. Full pedigree was also available for most of the sires and dams of the maiden ewes. Average spring fertility of Barbarine maiden ewes in the studied environment is 0.85±0.35 with significant effects of the year, flock and the average daily growth between 10 and 30 days (ADG 10-30). These sources of variation were included in the linear animal model to estimate genetic parameters. Heritability estimate of spring fertility was 0.05±0.02 while genetic correlation between spring fertility and ADG 10-30 was -0.29. There was a very close and positive (P < 0.001) relationship between the sires' EBV for the studied trait and the average fertility of their daughters. The 20% top ranked sires had a mean 0.97 spring fertility of their daughters in comparison to only 0.75 for the 20% bottom ranked sires. The results obtained in this study show that direct selection on spring fertility of maiden ewes would generate negligible genetic progress. They also highlight the importance of considering the sires' EBV's in the development of a breeding plan for the Barbarine sheep breed.
Rekik M.,International Center for Agricultural Research in the Dry Areas |
Ben Othmane H.,Institute National Of Recherche Agronomique Of Tunisie |
Lassoued N.,Institute National Of Recherche Agronomique Of Tunisie |
Sakly C.,Institute Superieur Agronomique Of Chott Meriem
Reproduction in Domestic Animals | Year: 2014
Contents: This study aims to develop at different seasons, for local North African Maure goats, synchronizing protocols simultaneously to the standard 'S' protocol using progestagens in association with prostaglandins and gonadotropin. In late May, 40 goats were assigned to either the 'S' protocol or to a protocol where oestrus and ovulation were induced by the buck effect in single-injection progesterone-treated goats and provoking early luteolysis using prostaglandin 9 days after exposure to bucks 'B'. During the 72 h after the treatments ended, 15 and 5 goats expressed oestrus in the 'S' and 'B' protocols (p < 0.01). Mean time to oestrus was shorter for 'S' than for 'B' goats. Ovulation rate averaged 2.1 ± 0.22 and 1.60 ± 0.35 for, respectively, 'S' and 'B' goats (p > 0.05). During mid-September, 60 goats were assigned to either 'S' treatment, 'PGF' treatment where oestrus and ovulation were synchronized using two injections of prostaglandin 11 days apart or to 'GnRH' treatment where the goats had their oestrus and ovulation synchronized with a GnRH (day 0)-prostaglandin (day 6)-GnRH (day 9) sequence. More 'S' goats were detected in oestrus over the 96-h period after the end of the treatments (88.8, 73.7 and 55% in 'S', 'PGF' and 'GnRH' treatments, respectively; p < 0.05). Mean ovulation rates were 2.3 ± 0.27, 1.33 ± 0.27 and 1.33 ± 0.27 for, respectively, 'S', 'PGF' and 'GnRH' goats (p < 0.001). Despite a similar ovulatory response to 'S' protocol, efficiency of prostaglandin and GnRH-based treatments should be tested in mid-breeding season. © 2014 Blackwell Verlag GmbH.