Fat-tailed Barbarine Research Articles

Impact of Body Reserves Dynamic on Productivity and Reproductive Performance in Fat-Tail and Thin-Tail Sheep Breeds over Contrasting Production Cycles.

Under climate change, animal breeding faces severe nutritional challenges, exhibiting their resilience and efficiency to survive and produce. The animals' robustness can be evaluated through the use and reconstitution of body reserves (BR). This study investigated the dynamics of ewes' BR, measured through body weight (BW) and the body condition score (BCS), and their effect on production performances of 480 ewes belonging to fat-tailed Barbarine (BB) and thin-tailed Queue Fine de l'Ouest (QFO) ewes over two consecutive years. The BW and BCS were recorded across physiological stages. Reproductive parameters and lambs' growth were calculated. For both years and breeds, the decrease in the BCS between mating and lambing showed BR mobilization to balance nutritional restrictions, which continues until suckling; after weaning, a BR accretion was noted. The lambs' birth weight was similar regardless of the dams' BCS at lambing, though it was lower in the second year (3.5 vs. 4 kg). Lambs' growth parameters depended on ewes' BCS at lambing and weaning. Fertility rates changed with BCS changes and the higher values (80%) were recorded for ewes with BCSs between 2 and 2.5. However, prolificacy was similar for both breeds and years (p > 0.05). In conclusion, ewes have developed adaptative capacities through BR mobilization to cope with environmental challenges and successfully rear their offspring. To maintain a high offspring growth rate, it is recommended to plan correct flock nutrition during suckling.

Effects of rosemary (Rosmarinus officinalis) by-products and linseed (Linumusitatissimum) intake on digestibility, body weight gain, and estimated tissular composition in cull fat-tailed ewes.

The aim of this study was to evaluate the effect of rosemary (Rosmarinus officinalis) residues (RR) as dietary supplement in association with linseed (Linumusitatissimum) on digestive aspects and body weight (BW) gain in fat-tailed Barbarine ewes. To achieve this, 24 cull ewes (BW: 33 ± 2.7kg) were divided into four groups receiving a basal diet composed of 500g of straw for two groups (S) and 300g of straw in addition to 200g of RR for two other groups (R). All animals received 750g of concentrate; the usual concentrate (UC) was offered for one S (S-UC) and one R group (R-UC); the linseed concentrate (LC) was also offered for one S (S-LC) and one R group (R-LC). The fattening and digestibility trials lasted 90days. The dry matter (DM) intake and digestibility were similar across the groups. However, the crude protein (CP) intake and digestibility and the neutral detergent fiber intake were significantly affected by the treatments (P > 0.05). The nitrogen intake (NI), the fecal, and retained nitrogen were significantly affected by the regimen (P < 0.05); however, the urinary nitrogen was unchanged. The nitrogen balance was positive for all groups averaging 60% of the NI. The ruminal pH, ammonia nitrogen, and protozoa concentration were not affected by the RR intake and linseed supply; however, the control time affected significantly these parameters. Final BW, the average daily gain, the muscle, and fat contents were neither affected by the basal diet nor by the concentrate type (P > 0.05). In conclusion, the RR intake in association with linseed did not alter the animal's performances by improving their productive characteristics and consequently, the commercial value of this sheep's category.

Genetic structure of Tunisian sheep breeds as inferred from genome-wide SNP markers

Abstract Assessing the status of genetic variability of native sheep breeds could provide important clues for research and policy makers to devise better strategies for the conservation and management of genetic resources. In this study, a genetic investigation of Tunisian sheep breeds using a genome-wide scan of approximately 50,000 SNPs was performed. To reconstruct genetic structure and relationships among four sheep breeds, 40 samples belonging to fat-tailed Barbarine, Queue Fine de l’Ouest, Noire de Thibar and D’Man breeds were genotyped using Illumina Ovine SNP50 BeadChip. Tunisian breeds averaged 96 % polymorphic loci with an expected heterozygosity (He = 0.36). Genetic analysis of relationship between breeds using Bayesian clustering, MDS and Neighbor-Network analysis, and estimation of FST genetic structure, highlighted the genetic differentiation of Noire de Thibar breed from the other local breeds, reflecting the effect of past events of introgression of European gene pool. The Queue Fine de l’Ouest breed showed a genetic heterogeneity and was close to Barbarine and D'Man breeds, as evidenced by MDS and the lowest level of differentiation with Barbarine breed (FST = 1.8 %). The D'Man breed shared a considerable gene flow with the thin-tailed Queue Fine de l'Ouest breed. Possible factors explaining the genetic patterns observed, such as considerable gene flow probably due to anthropogenic activities in the light of population management and conservation programs.

Effects of the fat-tailed ewes' body condition scores at lambing on their metabolic profile and offspring growth.

This experiment aimed to evaluate the effect of body condition score (BCS) of fat-tailed Barbarine ewes at lambing on their metabolic profile around parturition and lamb's growth. The experiment was carried out on 69 Barbarine ewes, divided into three groups according to BCS, which were inferior to 2, between 2 and 2.5 and superior to 2.5 for the thin, middle and fat group, respectively. Along the trial, all groups received the same dietary treatment based on hay, pasture and concentrate.Birth weight (Bi-W), weights at 30 and 70 d (W30 and W70) and average daily gains (ADGs) of lambs were recorded. Metabolites were determined at late pregnancy and at the beginning of lactation. Ewes' BCS at lambing had no effect on lambs' Bi-W (), which was 3.8, 3.8 and 3.9 kg, respectively, for thin, middle and fat groups. However, W30, W70 and ADG increased with a mother's BCS. A positive correlation between lamb growth parameters and ewe body weight and BCS at weaning was recorded. Energetic metabolites (glucose and triglycerides) and proteic metabolites (creatinine, total protein and urea) were similar among groups according to BCS but significantly different between pregnancy and lactation stages except triglycerides and urea. In conclusion, BCS may be used as dietary management tool during ewe lactation. With the transition from pregnancy to lactation, the content of some metabolites has changed irrespective of BCS; this aspect needs more investigations.

Seasonal variation of lungworm infestation of ewes at Sidi Bouzid slaughterhouse (Central Tunisia)

Respiratory strongyloses are among the most important diseases affecting sheep reared in various farming systems in many countries. In Tunisia, farmers without any scientific background carry out the control of these parasites. A survey was performed in a slaughterhouse in Sidi Bouzid District (Central Tunisia) to assess the prevalence of sheep infestation by lungworms. The study lasted 12 months and involved 720 of the slaughtered ewes. Fecal samples from each ewe were collected and examined by Baermann’s technique. Sixty-eight samples were infested with pulmonary nematode larvae (9.4 ± 2.1%). The population was dominated by Protostrongylus rufescens (4.4 ± 1.5%), followed by Dictyocaulus filaria (2.6 ± 1.2%), Cystocaulus ocreatus and Neostrongylus linearis (1.3 ± 0.8%), and finally Muellerius capillaris (0.3 ± 0.4%), whereas mixed infestations concerned 0.4 ± 0.5% of samples. Lungworm infestation was observed in all age groups with no significant difference (p = 0.64). In addition there was no significant difference in infestation between fat-tailed Barbarine (10.8 ± 3.6%) and Queue fine de l’Ouest (Western Thin Tail) (8.5 ± 2.6%; p = 0.31) sheep breeds. The lowest prevalence was recorded in spring (6.7 ± 3.6%) and the highest in winter (11.7 ± 4.8%), but the difference between seasons was not significant (p = 0.32). This study concerning the activity dynamics of lungworms should be completed by a monitoring project to determine the economic importance of these infestations and provide a solid basis for the establishment of specific control programs against these parasites in Tunisia.

Reproductive response of fat‐tailed Barbarine ewes subjected to short‐term nutritional treatments including spineless cactus (Opuntia ficus‐indica f. inermis) cladodes

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 21days, 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 (≥6mm; 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.

Assessment of mating management effect on genealogical parameters highlighting the genetic variability in a not closed fat-tailed Barbarine sheep pedigree

Abstract. The Barbarine sheep is generally managed within small interconnected herds. The goal of the present work is to investigate the effect of the mating management on genetic variability in a registered flock which starts showing a productivity falling, especially in lamb’s survival and this despite a practice of outbreeding. Pedigree data of 11136 animals born between 1977 and 2007 were used to compute genealogical parameters. A first investigation of the lambs-parents relationships highlighted two periods that we denoted: P1 and P2. During P1, the mating strategy had been progressively based on animals born within the flock, whereas during P2, ewes and rams coming from outside the herd were gradually introduced as parents with unknown genealogy. This change in matings policy has been emphasised by plotting equivalent complete generations averaged whether by year of birth or maximum number of traced generations. All the computed genealogical parameters have been affected by the matings policy change and especially the individual average relatedness and realised effective size, which seem to be powerful tools to monitor the genetic variability within a population that is not closed to exchanges. An important effect of pedigree depth has been detected; this would require special attention to the matings of individuals with deepest genealogy. In spite of this effect, the heterozygote deficiency within the herd confirmed that the genetic variability has not been much affected along the flock life, which confirms that the decline in productivity should not be allotted to matings’ policy, but probably to other management factors.

Merits of the fat-tailed Barbarine sheep raised in different production systems in Tunisia: digestive, productive and reproductive characteristics

Barbarine sheep is the dominant breed in Tunisia. This fat-tailed breed present in all production systems is characterised by metabolic and digestive adaptation to the contrasting environment conditions prevailing in the country (heat stress, water deprivation, salinity etc.). The fat tail (1.5 to 7kg) is an energy reservoir that is used in periods of feed scarcity. Moreover, the rumen of this breed harbours a microflora enabling it to valorize low-quality roughages and native range vegetation. Barbarine sheep could make benefit from a wide range of local feed resources like fodder shrubs (e.g. cactus and oldman saltbushes), tannin-containing shrubs (e.g. Acacia cyanophylla) and agro-industrial by-products (e.g. olive cake, bran etc. conserved in the form of feed blocks or pellets). It has a very shallow anoestrous, the intensity of which is dependant upon nutrition conditions rather than day length as temperate breeds. Productive and reproductive performances of late pregnant-early suckling, pre-mating ewes and also rams of this breed are not affected when some alternative feed resources replace common feedstuffs which are expensive and cannot afford regularly to smallholders. In brief, the merits of the Barbarine sheep in the production systems and other main adaptive mechanisms of this breed are discussed in this paper. The prospective of Barbarine sheep husbandry in the system dynamics, climate change and the evolution of the socioeconomic context are also envisaged.

The effects of diet, slaughter weight and docking on growth, carcass composition and meat quality of fat-tailed Barbarine lambs. A review

This review summarises the main factors that influence meat production and quality in fat-tailed Barbarine (FTB) lambs. As a general feature, FTB lamb's growth is moderate, and the average daily gain ranges between 100 and 350g. The carcass being relatively fatty, carcass fat content varies from 10% to 32%; white fat and rose meat are often dominant in these carcasses. The meat fatty acid profile of this fat-tailed breed is similar to that of thin-tailed ones, with a prevalence of palmitic, stearic and oleic acids. The order of dissected adipose tissues accumulation, estimated by allometry coefficients, is in agreement with observations in thin-tailed sheep. However, tail fat allometry coefficient is closer to kidney fat values rather than to the subcutaneous one. Concerning effects of feed level, growth of FTB lambs fed silage is higher than those fed oat hay. With moderate concentrate supply, FTB lambs' growth is more pronounced on pasture diet than on the feedlot (FL) diet. Furthermore, at similar slaughter weights, carcasses of lambs fed pasture diet have less tail and carcass fat than those from lambs fed FL diet (5% and 18% vs. 9% and 24% for grazing and FL lambs, respectively). No difference in fat colour, fat firmness or cooked meat flavour is observed between carcasses obtained at different slaughtering weight (i.e. from 25 to 35kg). The tail docking of FTB improved lambs' growth particularly before weaning. Its effect on carcass composition and fat proportion depends on stage of slaughtering and type of fattening diet. For suckled lambs (4months), the docking resulted in the lower carcass fat weight (and proportion), while for fattened lambs, carcass composition was similar for all types of lambs. Overall, FTB lambs always grow slower than Noire de Thibar lambs. This is particularly pronounced during the fattening phase. Then, for FTB breed, the possibilities to obtain heavy carcasses are at risks of fat accumulation, 22.8% vs. 14.4% for FTB and Noire de Thibar thin-tailed lambs, respectively. However, the main advantage of FTB breed is that adults are well adapted to food scarcity and may produce lambs even under harsh conditions.

Comparison of growth curves of lamb fat tail measurements and their relationship with body weight in Babarine sheep

A total of 695 fat-tailed Barbarine lambs born in two flocks between 1995 and 1997 were recorded for growth and fat tail measurements according to “standard growth recording protocol”. Recorded traits are body weight (BW) and the following fat tail characteristics: upper circumference (UFTC), lower circumference (LFTC), upper width (UFTW), lower width (LFTW), upper depth (UFTD), lower depth (LFTD) and tail length (FTL). Lamb body growth performance and tail measurements are analyzed from two points of view. Firstly through the adjustment of a growth curve chosen among the following: Brody, Logistic, Gompertz and Bertalanffy functions. Secondly, age-adjusted weight and tail measurements (10, 30 and 70 days) were analyzed and average daily gains (ADG) were calculated. All functions (Brody, Logistic, Gompertz and Bertalanffy) fitted closely body weight and fat tail measurements of Barbarine lambs for the recording period (up to 120 days), while the Bertalanffy function provided more accurate estimation of the asymptotic value (adult size) for the weight and tail measurements. High significant correlations ( p < 0.01) were obtained between body weight and tail measurements. However, the LFTW-ADG had the highest correlation with BW performance, and was therefore the best indicator of the state of lamb fattening. Furthermore, the LFTW-ADG recorded between 10 and 30 days of age has a higher correlation with lamb BW performance at later age (30–70 days) than those recorded at the same period (between 10 and 30 days), indicating that lambs with higher fat storage during the suckling period express better performance at later ages. Therefore, this study confirms the role of the tail fat as an adaptive character of the Barbarine breed and most likely of other fat-tailed sheep breeds.

Live Weight Changes and Their Relationship with the Ovarian Status of Maiden Fat-Tailed Barbarine Ewes

The current study assessed the effect of the pattern of live weight change on the ovarian function of maiden Barbarine ewes at approximately 1 year of age. For this purpose, a total of 171 weaned ewe lambs (mean live weight ± s.d. 34.7±3.07 kg and mean age ± SD 196±10 days at weaning) were selected for the experiment. Adjustment of live weight variation was used. Based on the slope of the curve, animals were grouped into three classes LWCI (n=46), LWCII (n=91) and LWCIII (n=34) with live weight loss being highest in LWCI and lowest in LWCIII. Following laparoscopy at 13 months of age, the proportion of ewe lambs found cycling in LWCIII (85.3%) was higher in comparison to animals in LWCI (43.4%; P&lt;0.001) and tended to be superior to those in LWCII (61.5%; P&lt;0.05). Following synchronisation with progestagen of the females found cycling, levels of plasma IGF-I concentrations between 6 and 42 hrs after removal of sponges were not significantly different between the three classes of live weight, and respectively averaged 94.2, 90.8 and 89.8 µg/l for LWCI, LWCII and LWCIII females. Levels of estradiol were also not significantly different between the three groups (0.73, 0.70 and 0.67 pg/ml for LWCI, LWCII and LWCIII ewe lambs, respectively). It was concluded that, in low input systems of semi-arid and arid Tunisia, mating ewe lambs at the approximate age of 1 year is likely to lead to depressed reproductive performance particularly when the summer live weight-loss is elevated.

Relationships among carcass composition and tail measurements in fat-tailed Barbarine sheep

Relationships among carcass composition and tail measurements in fat-tailed Barbarine sheep

Performance of the fat-tailed Barbarine sheep in its environment: adaptive capacity to alternation of underfeeding and re-feeding periods. A review

The Barbarine sheep is characterised by a fat-tail, whose mass varies between 1 and 4 kg. Its management is traditionally based on spring mating. The ability of this fat-tailed ewe to mobilise its body reserves has been demonstrated in lactation and the dry period by experimentally varying the food supply. The severely underfed ewe (200 g oat hay) can survive 161 days and lose 36% of its body weight (BW), with a change of 8.8 kg of dissected adipose tissue (AT) and 3.4 kg of muscle. It reached this stage with an empty BW of 24 kg containing 12% of AT. The fat tail exerts a role as a body reserve mainly through its mass rather than through its ability to be rapidly mobilised. In such situations, plasma NEFA and 3-hydroxybutyrate concentrations are first almost doubled, then decline in permanently underfed ewes, showing the ability of Barbarine ewes to adjust their lipid metabolite concentration in order to limit the toxic effects of high concentrations and therefore prolong survival. By the end of a re-feeding period, Barbarine ewes returned to their initial BW, lipid and protein mass. This breed has a good fertility, which can, however, be depressed in cases of undernutrition. However, if the mating period is extended, the overall reproductive performance is generally satisfactory. Poor nutrition during pregnancy may reduce lamb birth weight and affect subsequent growth, however, in traditional conditions, ewe and lamb mortality rates are surprisingly low in this breed. In normal birth weighted lambs, the post-weaning growth performances of grazing lambs are moderate but in feedlot conditions the conversion rate is rather low and carcass adiposity is high. This review shows that the Barbarine sheep, and specially the ewe, is well adapted to the local conditions mainly because of its high fertility and its ability to deposit and mobilise body reserves.

Relationships among carcass composition and tail measurements in fat-tailed Barbarine sheep

A total of 1392 records collected on 87 Barbarine fat-tailed lambs was used to predict in vivo carcass composition (tail fat, body fat and body muscle) from body weight (BW) and some fat-tail measurements. Lambs were 4–12 months old and weighed 21–48 kg. Measurements included body weight, upper and middle tail-depth, upper and middle tail-width, upper and middle tail-circumference and tail-length. After slaughter, omental, mesenteric, tail and dissected fat in the carcass were separated and weighted. Total body fat (TBF) corresponds to the sum of these fat depots. Weight of tail fat and TBF varied from 0.18 to 2.23 kg and from 0.98 to 7.63 kg, respectively and were highly correlated ( r=0.91; P<0.01) as well with all tail measurements. The highest correlations ( r>0.8) were observed between all fat depots and circumference measures. The best accuracy was obtained in the prediction of tail fat and TBF from circumference of upper and middle tail, width measure and BW (R.S.D.=219 and 611 g, respectively; P<0.01). This study showed that body fat could be predicted in vivo using simple tail measurements in the Barbarine fat-tailed lambs.

Relationship between ewe body condition at mating and reproductive performance in the fat-tailed Barbarine breed

The relationship between reproduction performance in early May and ewe body weight (BW), body (or tail) condition score, the week before the rams were introduced into the flock, are presented for the Tunisian fat-tailed Barbarine breed grazing natural ranges in central Tunisia. Dur- ing 2 contrasting years, 2 flocks (130 to 170 mature ewes each) differing by prolificacy (120%: Control and 160%: Prolific) and mature size (50 and 45 kg) were weighed and scored (according to 2 methods based on back fat thickness, BCS and on tail size, TCS), just before the introduction of rams. Rainfall during the pre-mating periods induced highly significant differences ( P < 0.01) in animal body condition. In both flocks, fertility was equal to 75% and 92-96% for groups of ewes whose pre- mating BW was respectively lower or higher than 35 kg. Similarly, the group composed by the 123 leanest ewes (less than 1.5 BCS) was significantly less fertile than the remainder of the flocks: 86% versus 91-95%. In both flocks, the higher the ewe BW, BCS or TCS at the beginning of the mat- ing period, the earlier the lambing date and the higher the litter size. The first and the last lambing ewes (first 2 weeks and third month) weighed over 50 kg and only 35-40 kg, respectively, when rams were introduced into the flock. According to BW, BCS or TCS classes, litter size varied from 1.0 to 1.3 and from 1.2 to 1.8, respectively, in the C and P flocks. Target BW, BCS and TCS at mating to obtain early lambing and adequate litter size in Barbarine flocks can be proposed. According to ewe size, the following values: 39 or 50 kg for BW, 2.1 or 3.0 for BCS and TCS, mean values of the group of ewes lambing during the second month, can be considered as minimal for the whole flock. A second method, taking into account the within-flock animal variability can be used. The percent- age of too emaciated ewes (less than 35 kg BW and back and/or tail condition score < 1.5) must be lower than 4 to 10% for BW, 6 to 8% for BCS and 10 to 15% for TCS. fat-tailed sheep / mating period / body condition / reproduction performances