peer reviewed | Lactation persistency (LP) has been neglected over time in genetic evaluations of dairy goats. The main reason for this is the difficulty to infer about the lactation curve shape. However, some lactations models such as Wood seem to be appropriate to provide persistency estimates under biological viewpoints. The aim of this study was to fit the Wood lactation model as well as to calculate and evaluate LP as selection criteria in dairy goat breeding programs through genetic parameters estimates. A total of 23,265 first lactation test day milk yield observations from 900 animals were used. The Wood random regression model was primarily fitted to estimate the lactation curve parameters (a, b and c), and then LP and total milk yield (TMY). Posteriorly, a multi-trait animal model was fitted considering simultaneously LP and TMY. The heritability estimates were 0.31 and 0.04 for TMY and LP, respectively. Based on the low LP heritability, selection based only on this trait might be inefficient. In conclusion, the results of this study suggests that selecting for high milk yields might result in high persistency since the genetic correlation between LP and TMY was moderate (0.39).

peer reviewed | In genetic breeding programs, body weight is measured overtime, and is historically the main source of information from animals. Random Regression Models (RRM) have been frequently used in beef cattle evaluations, but can significantly contribute to genetic progress in all species of economic importance. To our knowledge, there are no scientific studies using RRM to evaluate Polled Nellore. We aimed to estimate genetic parameters by using RRM as a way to provide basis for guidelines development of growth of this breed. The models included direct genetic and maternal genetic, permanent environmental and maternal permanent environmental as random, contemporary groups as fixed and cow age at calving as covariate effects. The residual variances were modeled from homogeneous to six heterogeneous classes. The model of orders 4, 2, 2 and 2 for direct additive genetic, maternal additive genetic, maternal permanent environmental and permanent environmental had greater performance according to statistical criteria (smaller AIC and BIC values). Estimates of direct additive genetic increased over time (range 0-5,000 Kg2) and the heritability estimates were up to 0.73 along the growth curve. Maternal heritability estimates were low, with values close to zero. Genetic correlations between ages ranged from moderate (0.60) to high (0.97). Random regression models may be an alternative to describe the changes in body weight variances throughout lifetime.

peer reviewed | La République Démocratique du Congo (RDC) souffre, à l’instar d’une majorité de pays africains, d’une précarité alimentaire conséquente. Le développement du secteur de l’élevage y est une pièce importante de la stratégie de lutte contre cette insécurité alimentaire, par l’apport de protéines de haute qualité aux populations pauvres ainsi que plus globalement par la création de richesses et la diversification du secteur agricole. A ce titre, le secteur avicole offre incontestablement, par son cycle de production court, une solution rapide et abordable par le plus grand nombre. Cette étude aborde les contraintes à la production de la poule locale au Bas-Congo. Plusieurs facteurs y sont identifiés, tels que les pathologies, l’alimentation, l’habitat et les prédateurs. L’amélioration de la situation économique et nutritionnelle des paysans de la Province du Bas-Congo peut être envisagée en améliorant le potentiel de production des poulets de race locale. Afin d’y arriver, une attention particulière doit être accordée à une alimentation équilibrée et une meilleure conduite générale de l’élevage, incluant un accès aux soins vétérinaires. L’amélioration génétique des races locales est également une voie envisageable, pour autant que l’adéquation entre l’animal et le cadre de son élevage soit respectée.

International audience | This paper deals with designing a cheap and easy-to-attain method to replace weighing for estimating the body mass of goats. Several models on the relationship of heart girth (HG) to live weight (LW) were evaluated using Creole of Guadeloupe goats (376 males and 258 growing females). The best fit was obtained with a Gompertz model: LW = 155 * exp(-7.91 * exp(-0.0215 * HG)), which provided an adjusted R² = 0.98 and a 95% confidence interval of the prediction values below 5% within most of the LW range. The LW of breeding goats (420) was fitted by the following quadratic model taking into account the HG and paunch girth (PG): LW = -28.1 + 0.539 * HG + 0.00221 * PG², which provided an adjusted R² = 0.95 and a 95% confidence interval of the prediction values below 1% within most of the LW range. The first model allows a tape measure graduated in kg to be used on goats except breeding females. The second model allows the building of an abacus to provide the estimated LWs of breeding goats from the HG and PG values. Further correction might be achieved by adding the goat body condition score. Such cheap tools should be very useful for goat farmers, most of whom lack reliable weighing devices.

Notice a Reprendre pas de Clé UT au 5 Mai 2017 | The purpose of this trial was to study the possibility of a total replacement of the soya bean meal by the seeds of bean ( Vicia faba major L) in the feed of the fattening rabbit. From 42 days (weaning) old and for 5 weeks, 68 rabbits of white Algerian population were housed in collective cages (4 rabbits / cage) and were allotted in two groups: 34 rabbits of the control group received ad libitum a pelleted feed with soya bean meal (15 %), and 34 rabbits of the experimental group received a feed with 15 % of beans seeds as a total replacement of the soya meal. The performances were not significantly influenced by the type of feed. From 42 to 77 days of age, the growth was 25.6 g / day, the feed intake was 97 g / day and the feed conversion ratio was 3,75. Yield and carcass characteristics were not influenced by the type of feed. In conclusion, the substitution of soya meal by bean seeds in the classical feed (alfalfa 32%, barley 25%, wheat bran 20%, soybean meal 15%, straw 6%, vitamins and minerals 2%) did not influenced the performances of the growing rabbit. The seeds of broad bean is an alternative source of proteins to soya bean meal for the growing rabbit. Choosing this option would contribute to food self-sufficiency in Algerian rabbit breeding and would reduce the feed costs. | Le but de cet essai est d’étudier l’effet d’un remplacement total du tourteau de soja par des graines de fève (Vicia faba major L) dans l’alimentation du lapin en croissance. A partir de l’âge de 42 jours (sevrage) et durant 5 semaines, 68 lapereaux de population algérienne blanche élevés en cages collectives (4 lapins/cage) ont été répartis en deux lots : 34 lapereaux du lot témoin ont reçu ad libitum un aliment granulé équilibré à base de soja (15%), et 34 lapereaux du lot expérimental ont reçu un aliment à base de 15% de fèves en remplacement total du tourteau de soja. Les performances n’ont pas été influencées (P˃0,05) par le type d’aliment. De 42 à 77 jours d’âge, la vitesse de croissance a été de 25,6 g par jour, la prise alimentaire 97 g par jour et l'indice de consommation de 3,75. Les rendements et paramètres de la carcasse n’ont pas été influencés par le type d’aliment.En conclusion, la substitution du tourteau par de soja par des graines de fève de l’aliment classique (luzerne 32%, orge 25%, son de blé 20%, tourteau de soja 15%, paille 6%, vitamines et minéraux 2%) n’a influencé ni la croissance, ni les performances à l’abattage des lapins. La fève s’avère une source protéique alternative au tourteau de soja dans un aliment équilibré pour le lapin en croissance. Le choix de cette option contribuerait à l’autonomie alimentaire en cuniculture algérienne et réduirait le coût de l’alimentation

A cross-sectional survey on fasciolosis was conducted in March 2009 in Taveta Division. Bura Ndogo, Challa, Kiwalwa, Kitogoto and Lake Jipe Gicheha settlements participated in the study. A total of 338 (197 cattle, 111 goats and 30 sheep) faecal samples from 42 herds were examined using the sedimentation technique. Similarly, husbandry practices and aspects of herd owner education in the same settlements were captured using a standard questionnaire. Selective deworming targeted at the sick and /or weak looking animals was done by some herd owners interviewed. Fasciolosis prevalence in cattle, goats and sheep was 25.9%, 23.4% and 33.3%, respectively. Extensive grazing and age stratum 7 - 12 months were identified as potential fasciolosis risk factors with the latter being significantly (p<0.05) associated with the disease. On the contrary, home watering, training on livestock husbandry practices and deworming were significant (p< 0.05) protective factors of fasciolosis. Improved husbandry practices assisted by the selective anthelmintic treatments targeting the young animals were identified as feasible fasciolosis control options for Taveta division. In conclusion, the results of the study have clearly shown that fasciolosis is widespread in Taveta Division making it necessary for further longitudinal studies on the disease for establishment of an effective control programme

The current study optimised breeding schemes for litter size (LS), lambing interval (LI), body weight (BW) and gastrointestinal parasite resistance for sheep in Kenya. Selection for the breeding goal traits was performed in a conventional way using information on phenotypes only. For gastrointestinal parasite resistance, information on genetic makers was used, with faecal egg count (FEC) as an indicator trait. Selection for parasite resistance was partly based on field measurements and the possibilities for marker-assisted selection (MAS) were explored. Several selection schemes were defined based on whether a classical selection only was used (Latin number 1), a quantitative trait loci (QTL) for FEC was assumed to be available (2), that the correlation between FEC and BW was assumed to be positive (unfavourable-Roman I) or negative (favourable- II) and finally how FEC was included in the index (i.e., no inclusion (A), with FEC (B) or with FEC QTL (C-F)). The schemes with overlapping generations were evaluated using the computer program SelAction. Rams, ewes and total selection responses in US dollars ($) per animal, and rams' and ewes' accuracies for each scheme with a favourable or unfavourable correlation were estimated. The differences in total selection responses between schemes that did not include FEC in the selection index resulted in a response of $0.16 in scheme 1AI and $0.20 in scheme 1AII. In schemes 1BI and 1BII, FEC was included in the index. The responses in scheme 1BI and 1BII were $0.165 and $0.217, respectively. The increase in response in schemes II compared with schemes I was due to a favourable correlation between BW and FEC. The different FEC index traits had a different effect on economic response. It should be noted that increased emphasis on selection for FEC will reduce the relative responses to the breeding goal traits BW, LS and LI. Consequently, the goal of selection for FEC should be to maintain acceptable levels of gastro-intestinal parasite resistance as well as sufficient improvement of LS and BW.

Grazing management and seasonality strongly influence the recovery potential of herbaceous vegetation in semi-arid rangelands of southern Ethiopia after history of heavy grazing. We investigated effects of management (enclosures versus grazed landscapes), age of enclosures and seasonality related to rainfall (i.e., independent variables) on herbaceous biomass, grass basal cover, herbaceous species abundance, species richness and diversity in a savanna rangeland of southern Ethiopia. We further assessed the relationship between the herbaceous biomass and species richness. Management significantly affected most of the herbaceous response variables (i.e., comparing enclosures and open grazed). Herbaceous biomass, grass basal cover, herbaceous species richness and diversity were greater in enclosures than in grazed areas. Rainfall was also influential on herbaceous biomass, grass basal cover, abundance of herbaceous species, herbaceous species richness and diversity. Herbaceous biomass, abundance and diversity did not however vary with the age of enclosures, while herbaceous species richness appeared to decrease as the age of enclosures advanced. Grass basal cover initially decreased and later on increased with the age of enclosures, so that the older enclosures disclosed improvement of grass basal cover.

Grazing management and seasonality strongly influence the recovery potential of herbaceous vegetation in semi-arid rangelands of southern Ethiopia after history of heavy grazing. We investigated effects of management (enclosures versus grazed landscapes), age of enclosures and seasonality related to rainfall (i.e., independent variables) on herbaceous biomass, grass basal cover, herbaceous species abundance, species richness and diversity in a savanna rangeland of southern Ethiopia. We further assessed the relationship between the herbaceous biomass and species richness. Management significantly affected most of the herbaceous response variables (i.e., comparing enclosures and open grazed). Herbaceous biomass, grass basal cover, herbaceous species richness and diversity were greater in enclosures than in grazed areas. Rainfall was also influential on herbaceous biomass, grass basal cover, abundance of herbaceous species, herbaceous species richness and diversity. Herbaceous biomass, abundance and diversity did not however vary with the age of enclosures, while herbaceous species richness appeared to decrease as the age of enclosures advanced. Grass basal cover initially decreased and later on increased with the age of enclosures, so that the older enclosures disclosed improvement of grass basal cover.