Sheep In Pens Research Articles

The type IV fimbrial subunit gene (fimA) of Dichelobacter nodosus is essential for virulence, protease secretion, and natural competence.

Dichelobacter nodosus is the essential causative agent of footrot in sheep. The major D. nodosus-encoded virulence factors that have been implicated in the disease are type IV fimbriae and extracellular proteases. To examine the role of the fimbriae in virulence, allelic exchange was used to insertionally inactivate the fimA gene, which encodes the fimbrial subunit protein, from the virulent type G D. nodosus strain VCS1703A. Detailed analysis of two independently derived fimA mutants revealed that they no longer produced the fimbrial subunit protein or intact fimbriae and did not exhibit twitching motility. In addition, these mutants were no longer capable of undergoing natural transformation and did not secrete wild-type levels of extracellular proteases. These effects were not due to polar effects on the downstream fimB gene because insertionally inactivated fimB mutants were not defective in any of these phenotypic tests. Virulence testing of the mutants in a sheep pen trial conducted under controlled environmental conditions showed that the fimA mutants were avirulent, providing evidence that the fimA gene is an essential D. nodosus virulence gene. These studies represent the first time that molecular genetics has been used to determine the role of virulence genes in this slow growing anaerobic bacterium.

Studies on the transmission of malignant catarrhal fever in experimental animals: Bali cattle in close contact with sheep

pregnant sheep and lambing sheep were conducted in two different periods and flocks of Bali cattle and sheep. On the basis of clinico-pathological findings and polymerase chain reaction (PCR) tests, the study revealed that MCF transmission has been successfully achieved in four Bali cattle that were in contact with lambing sheep, and in one Bali cow that was penned 100 metres away from lambing sheep pen. The polymerase chain reaction (PCR) detected the causal agent of MCF in peripheral blood leucocytes (PBL) and nasal, ocular and vaginal secretions of sheep. It is assumed that viruses in the secretion were spread by sheep causing five Bali cattle suffered with MCF. However, further studies on exact mode of transmission needs to be clarified particularly on the time and mode of viral transmission from reservoir to susceptible animals. Key words : Malignant catarrhal fever, experimental transmission, in-contact, Bali cattle, sheep

Polyethylene glycol is more effective than surfactants to enhance digestion and production in sheep fed mulga (Acacia aneura) under pen and paddock conditions

Chemicals that interfere with the formation of tannin-protein complexes were evaluated as dietary additives for mulga-fed sheep in pens and under paddock conditions. Condensed tannins (CT) in mulga inhibit protein digestion, and the use of chemicals to precipitate CT or dissociate CT-protein complexes may improve production from sheep consuming a mulga diet. In a digestion study with mulga-fed sheep in pens, provision of polyethylene glycol (PEG) at a rate of 6 g/day significantly (P < 0·05) improved nitrogen (N), phosphorus (P), and sulfur (S) balance, and apparent N, P, dry matter (DM), and organic matter digestibility, and the rate of liveweight gain. Addition of the surfactants SDS or alkanate 3SL3 to the diet of mulga-fed sheep did not improve N balance or digestion; however, apparent digestibility of P, and P and S balance, were significantly improved by SDS. Teric PE64, a compound structurally similar to PEG, significantly improved S balance, but not DM intake or N balance. For sheep consuming a predominantly mulga diet under paddock conditions, provision of PEG at a rate of 12 g/day significantly improved clean wool growth and liveweight gain compared with unsupplemented sheep, by 9% and 100%, respectively (0·809 v. 0·745 mg/cm2.day, and 44 v. 22 g/day). The studies demonstrated that although surfactants can affect mulga digestion, using PEG to precipitate CT is more effective to improve mulga digestion and animal production than the use of surfactants. However, the wool and liveweight production responses achieved with PEG were not sufficient to justify its wide-scale use for mulga-fed sheep. Consequently, alternative methods should be sought to reduce the negative effects of mulga CT on sheep production.

Contribution à l'étude des cercles de pierres en Pays Basque de France

ABSTRACT Of modest size and aspect, these circles of stone slabs constitute a noteworthy feature of the Basque mountainside. Bits of charred bone and vestiges of charcoal probably link them to incinerary rites in use from the Mid-Bronze Age to the end of the Iron Age. However, the contrast between their careful construction and the poverty of their contents indicates their symbolic nature, cenotaphs rather than real graves. They seem to be linked to pastoral activity in the mountains, being found near sheep pens and the tracks used by shepherds and their flocks. This specific characteristic may reflect phenomena of complex accultural processes among ancient peoples with strong traditions established in a mountainous region that appears to have been both a dynamic, innovative melting pot, and a sanctuary up to historical times, for the people, their language, and their protohistoric funerary rites.

Responses of young and mature wethers exposed to micromist cooling in feedlot environments

The responses of young and mature wethers to different cooling/housing environments were studied. In the first trial, 180 wether lambs were housed in closed or open pens. In the second, both young and mature wethers (60 of each) were housed in conventional feedlot sheep pens. Micromist cooling was installed in both types of shed. Although mist cooling considerably reduced ambient temperatures in open and closed animal pens, there was no significant improvement in live weight gains in lambs in the first experiment. Mist cooling in conventional sheep sheds resulted in a significant improvement in live weight gains. The young wethers were found to be more sensitive to heat stress than the mature.

Voluntary intake and in vivo digestibility by sheep of five lilies of Cenchrus ciliaris selected on the basis of preference rating

A study is reported on the voluntary intake and digestibility by sheep of five lines of Cenchrus ciliaris when grown as swards and cut at six different stages of growth. Previous studies with C. ciliaris grown in small rows had shown large differences between these lines in grazing preference by cattle. The ranking order for preference wasline31>10 = 23>30 = 36. When offered singly to sheep in pens the five lines could be divided into three groups according to their voluntary intakes. Lines 10 and 30 had the highest mean daily intakes of 56·1 and 57·6 g (kg W)-0·75 compared with lines 23 and 36 with low mean intakes of 48·5 and 48·6 g (kg W)-0·75. Line 31 was intermediate with a mean intake of 543 g (kg W)-0·. Mean dry matter digestibility of the five lines ranged from 0·577 to 0·597%. Lines 10 and 30 had the lowest digestibility. The difference in intake between the five lines was positively correlated with their proportion of leaf (r= 0·97). Low-intake lines (23 and 36) also had the highest proportion of seed head. It was concluded that selection of C. ciliaris on the basis of preference by cattle in a cafeteria study provided no useful guide to voluntary intake when the different lines were grown, cut, dried, chopped and fed separately to sheep.

Growth responses of young Merino wethers to ad libitum feeding of oat grain mixed with either lupin seed or a urea solution

Groups of 10 Merino weaners or hoggets were offered ad libitum 1 of 5 grain mixtures: oats alone (9.1% crude protein, CP), oats mixed with lupins (CP 12 or 15%), and oats sprayed with a urea solution to increase total nitrogen to an equivalent of 12 or 15% CP. In experiment 1, each grain mixture was fed with 10% milled cereal hay to sheep in pens for 98 days; in experiment 2 the sheep grazed wheat stubble for 84 days. In experiment 1, the liveweight gains of weaners and hoggets fed the lupin or urea mixtures were greater by 53-69% and 58-120�/o, respectively, than the daily 9.4 and 54.1 g/head gained on oats alone (P< 0.05). In experiment 2, liveweight gains of sheep fed these mixtures were, with 1 exception, greater by 95-1 54% than the 69.0 and 58.3 g/head gained daily by sheep fed oats alone (P< 0.05). Addition of urea to oats at the higher level (15% CP) tended to depress intake and liveweight gain, compared with the 12% CP level, and the effect was greater among hoggets. Wool production paralleled feed intake and liveweight gain. It is concluded that the daily growth rates of 90 to 130 g/head resulting from treatment of oats with up to 1.5% urea can be similar to those from oat-lupin mixes of equivalent CP (daily 85-150 g/head).

Native Fly Dispersal in the Field Evaluation of a Prospective Factory Strain of the Screwworm, Cochliomyia hominivorax (Coquerel) (Diptera: Calliphoridae)

Sterile flies from a prospective mass-production strain of the screwworm, Cochliomyia hominivorax (Coquerel), were tested in the field on two occasions between August and November 1981 in the Pacific coastal plain of Chiapas, Mexico. In Test I, flies were released over a 30-by-120-km area where all nine sentinel sheep sampling sites were located 5 to 23 km, including 5 sites <10 km, from the nearest perimeter. The maximum egg mass sterility rate (25%) was obtained by the third of 6 weeks of sterile fly releases. In Test II, flies were released over a 40-by-80-km area where all eight sentinel sheep pens were located 18.5 to 34.5 km from the nearest perimeter. For all pens, the maximum egg mass sterility rate (38%)was obtained by the fourth week. Egg mass sterility rates at sites considered well-insulated from the perimeter were statistically higher than sterility rates at sites considered poorly insulated. In Test II, distance from the sentinel sheep sampling sites to the nearest perimeter of the fly release area and egg mass sterility rate were positively correlated, and a maximum sterility rate of 60% was recorded. This relationship was attributed, at least in part, to the movement of native screwworm females into the test area from untreated areas.

Spacing behaviour of sheep in pens

Photographs were taken of sheep in holding pens, with open or covered sides, containing 10, 30 or 50 sheep at a density of 10 sheep per 6 m 2. The data were analysed by computer to produce maps of pen use, distance moved and direction of facing of individual sheep, and distance and bearing to the nearest neighbouring sheep. Standing sheep were spaced evenly throughout the pen and were orientated parallel to, and facing in the same direction as, the nearest neighbour. Lying sheep selected positions at random in covered pens, but lay down parallel and next to the sides of open pens. Pen size had little effect on spacing behaviour. Covering pen sides restricted movement and promoted more uniform dispersion of lying sheep in the pen. The results suggest that the design of the transition zone from a pen to a race could be improved by allowing two or more sheep to enter the race in parallel.

Variation in the wheat intake of individual sheep measured by use of labelled grain: behavioural influences

A preliminary experiment with sheep in pens demonstrated that wheat grain could be labelled with tritiated water so that when fed it could provide data that would allow accurate calculation of individual feed consumption. This techinque was used with two groups of sheep fed supplementary wheat grain in paddocks. Half of the animals had previous experience of grain feeding some eight months earlier and the others had not eaten grain. Individual diversity of intake could be estimated usefully by tritium labelling of wheat, which was fed to the sheep in a group. The experiment showed that there was a threefold difference in the amount of wheat eaten between the lowest and highest intakes. Further, animals with previous experience of grain feeding consumed the entire ration initially, but those without previous experience did not consume all of the ration until two weeks after wheat feeding began. Over the period of measurement the experienced sheep consumed about 13% more wheat than the non-experienced group. There were insufficient aggressive acts to establish a dominance hierarchy in either group, although the experienced sheep were more aggressive than the others. Aggressiveness by one sheep towards other sheep did not result in higher wheat intakes by the former compared with other sheep in the group. The results are discussed in terms of the variability in acceptance of such supplements by animals, and of the value, later in life, of early introduction of supplementary feeding.

Comparison of lupin varieties for grain yield, nutritive value of stubbles, incidence of infection with Phomopsis leptostromiformis and occurrence of lupinosis

The lupin cultivars Borre, Uniwhite, Fest, Uniharvest, Weiko III, CB46 and Ultra were grown for two years at Baker's Hill, Western Australia (640 mm average rainfall). Fest gave the highest grain yield in both years but the ranking of the other cultivars differed in the two years. Grain lost at harvest varied from 24 to 860 kg ha-1, being significantly higher from Weiko Ill and CB46. The nitrogen content of the grain of Weiko III and Ultra was significanlty higher than that in all other cultivars, and the pods of Ultra had a higher nitrogen content than pods of any other cultivar. In both years the stems and pods of Weiko Ill and Ultra had significantly lower concentrations of soluble carbohydrates, the stems fewer lesions from Phomopsis, and the sheep grazing the stubbles a much lower and less severe incidence of lupinosis than on all the other cultivars. In the first year liveweight gains over 63 days ranged from 2.9 kg on Fest to 7.5 kg on Borre. In the second year, when lupinosis was severe, there was a positive correlation between its severity and concentration of copper in the liver, and a negative correlation with zinc concentration. In another experiment Ultra and Unicrop had fewer Phomopsis lesions than CB46 and sheep grazing the stubbles less liver damage. Dry ewes grazed on stubbles of Uniharvest lupins planted at three different dates and on Fest lupins barely maintained weight but those grazed on wheat stubble lost 6.5 kg in 42 days. Stubbles from Uniharvest lupins sown at four different dates in two years all produced lupinosis when fed to sheep in pens. The diet selected by sheep from the stubbles was measured in two of the experiments. In both, stem, which is the most toxic fraction, made up at least 80 per cent of the diet from the time grazing started.

The Sites

I. The Ayiofarango ValleyE1 (M, GR, BM)A terrace at about the 200 m. contour, east of and above the road from Kaloi Limenes to A. Kyriaki, c. 100 m. from the point where the road crosses the watershed into the catchment area. The terrace is c. 150 m. (N.-S.) by 50 m. (E.-W.), bounded on the east by steep, bare upward gradients, and on the west by a steep downward slope covered only with low scrub. Two possible stretches of wall were found on the western slope, but the only certain structural remains were a modern sheep pen and a circular wall, c. 1–5 m. in diameter, which appeared to be a filled-in well. Abraded sherds were quite common on the western slope, but scarcer on the terrace.

Intake and liveweight response of sheep fed three ground and pelleted cereal straws

Wheat, oat and barley straws, ground and pelleted, with and without supplements of urea and minerals, were fed to groups of sheep in pens. Dry matter intake of oat straw was 53 per cent higher than that of wheat straw, which was 33 per cent higher than that of barley straw. Intake of straw was highly correlated with in vitro digestibility. Liveweight losses reflected changes in intake and were lowest on the oat straw and highest on the barley straw. Over all diets supplementation significantly increased intake and reduced liveweight loss.

In vivo digestibility of cell-wall polysaccharides of Setaria splendida and Lolium perenne dv. Kangaroo Valley.

A tropical and a temperate grass (S. splendida and L. perenne cv. Kangaroo Valley respectively) were cut at a young stage of regrowth and fed to sheep in pens. Although the fresh plants were chemically very similar, the apparent digestibility of the S. splendida (61'4%) was much lower than that of the ryegrass (76'1 %). Analyses of the faeces showed that the hemicellulose and cellulose in each grass were digested to a similar extent, but between species, the cell-wall polysaccharides of ryegrass were digested to a much greater extent than those of S. splendida (c. 79 and 49% respectively). Notable differences between the grasses were the hemicellulose A content of the faeces from sheep fed S. splendida, which was greater than that present in the fresh plant material, and the ryegrass hemicellulose B, which had a much higher arabinose content than that of S. splendida. Glucose and galactose, which were present in the fresh plant hemicelluloses, were absent in the faeces. The differences in apparent digestibility between the two grasses could not be explained in terms of their cell-wall polysaccharide content, but resulted from differential digestion of both the hemicellulose and cellulose of each species.

The origin of blood meals of female Culicoides pallidipennis trapped in a sheepfold in Israeil.

Precipitin tests were carried out on blood meals of 269 female Culicoides pallidipennis (Carter, Ingram & Macfie) trapped over a period of 12 months in the sheep pens of the Veterinary Institute at Bet Dagan, Israel. The results were as follows: 44.2% of the meals were not identified, 23% were from cattle, 17.8% from sheep or goat, 14.1% from the family Bovidae which could not be identified further and 0.7% from other mammalian hosts. The monthly average “forage ratio” for cattle during the trapping period was 1.3, whereas for sheep it was 0.2. The implications of these findings in relation to the epidemiology of bluetongue are discussed.

The effect of chewing by sheep in the release of nitrogen and soluble carbohydrates from plant cells

Three sheep in pens were fed cut white clover (Trifolium repens L.). On six separate days samples were collected through oesophageal fistulas and the length of the extruded pieces was taken as a measure of the amount of chewing and was related to the quantities of nitrogen and soluble carbohydrate released. Correlation coefficients of 0.84 and 0.77 were found between the amount of chewing and the release of nitrogen and soluble carbohydrate respectively.

Rumen fermentation of fresh herbage

1. On twelve occasions covering a complete seasonal cycle rumen mierobial end-product concentrations were measured in a group of sheep allowed to graze a pasture for 1 hr. Considerable differences were obtained in the rises in total volatile fatty acid and ammonia after feeding, in average rumen protein nitrogen and in free mierobial count.2. Seven samples of fresh herbage wfere fed to groups of sheep in pens at different levels of intake. Increase in feed intake with five of the herbages produced significant increases in rumen ammonia and total volatile fatty acid and with one herbage there was a significant increase in protein nitrogen. Free mierobial count was measured after feeding three herbages and was found to be independent of intake level.

Effects of pasture maturity on the diet of sheep

This paper compares the changes from early spring to summer in the digestibility of the diet of sheep grazing on phalaris -subterranean clover pasture, with changes over the same period of a similar pasture cut. and fed to sheep in pens. Data from a continuous digestibility trial in pens between September and December 1958 showed that the voluntary dry matter intake of sheep was restricted when the dry matter content of the pasture was below about 25%. From an early vegetative stage of growth through to early flowering of the phalaris, the organic matter digestibility of the whole pasture declined only from 79 to 76%. The diet selected by grazing sheep did not decline in digestibility, as measured by a faecal nitrogen index method, until 2 or 3 weeks after the decline in the whole pasture. With flowering and senescence of the pasture, the organic matter digestibility declined rapidly to 53%. Factors influencing this marked decline are discussed.

Economic Dose of Groundnut Cake (as Manure) for Enhancing Yields of Irrigated Ragi

In the Grow More Food Campaign one of the ways recommended for stepping up production is manuring of crops. Ragi is an important crop among millets grown under irrigated conditions and as a staple food crop it is important in districts like Salem. Visakhapatnam, Chicacole and Coimbatore, where the crop is cultivated extensively. This grain crop is usually manured either with farmyard manure, or by sheep penning. But in these methods due to limited availability of the manures, either increasing the dosage or extending the area of application possible beyond is a certain limit. As an alternative groundnut cake is being advocated by the Agricultural Department, since large quantities of the same are available in districts growing groundnut and having oil-extracting mills. With the idea of finding out the economic dose of this manure to ragi grown under irrigated conditions, investigations were done at the Sugarcane Research Station, Anakapalle, during the period 1946 to 1949 and the results are summarised in this note.

THE CULTIVATION OF AMARANTHUS AT REGA

In the Vizianagaram market, what is known as Rega thotakura' (a kind of amarantlius) is a speciality. It comes down from Rega, a small village adjoining the town. The variety cultivated is known as Pedda thotakura and is grown for its stalk which is allowed to mature. This variety is distinct from Mokka thotakura of which the whole plant is used as a green when comparatively tender. The special merit of Rega thotakura is that while the outer layer of the stem is hard, the inner portion is soft, non-fibrous and sweet when cooked, these qualities not being developed to anything like the same extent in the amaranthus grown elsewhere. Even at Rega, the above qualities are said to develop best on only high lying dark red loams, the plants grown on other soils being said to be inferior. The poorer the soil the better is the quality. Sheep pen- ning combined with the application of penta which consists mostly of ashes is also said to give the best quality.