bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of restricted feeding and re-feeding of Barbarine lambs: carcass composition and fatty acid composition
Authors: Atti N. , Rouissi H. , Mahouachi M.
Published: February 2006

Abstract Fifty intact male Barbarine lambs were used to assess the effects of restricted feeding and re-alimentation on carcass composition and fatty acid (FA) composition of intramuscular fat. Five lambs were slaughtered at the start of the trial; the remainder were randomly allocated to three groups. One group was offered only stubble grazing (low: L), another, also on stubble, received, indoors, an average of 80 g dry matter (DM) of soya-bean meal per day (medium: M); the third group was kept indoor and had free access to hay and 450 g of concentrate (high: H). At the end of this restriction period (70 days), five lambs per group were slaughtered. The 10 remaining animals in each group were divided into two groups receiving concentrate and hay ad libitum. The crude protein (CP) content of the concentrate was 160 and 210 g/kg DM in the two treatments, respectively. At the end of the trial all animals were slaughtered at 37·61 ± 2·05 kg live weight.

In the restriction period, bone tissue was similar in terms of mass for all diet treatments. The absolute weight of muscle and fat in carcasses was higher for unrestricted sheep (H) than for restricted ones, but L and M lambs had proportionately less fat and more muscle than those given food indoors. Intramuscular fat composition was similar for all the treatments. During this period, the carcass gain of M lambs had the highest proportion of muscle and the lowest fat concentration, which is the better composition. At the end of the compensating period, all carcasses contained the same quantity of bone and muscle, but unrestricted sheep had significantly more fat than compensating ones. So, carcasses of compensating animals contained relatively less fat (240 v. 310 g/kg) and more muscle (550 v. 500 g/kg) than unrestricted ones. The carcass gain of lambs with an earlier nutritional history on L had the highest muscle and the lowest fat concentration. The intramuscular lipid composition in terms of fatty acids showed differences between treatments. Unrestricted animals contained more C14: 0 and C16: 0 and compensating animals more C18: 2 and a higher proportion of polyunsaturated fatty acids (PUFA) and PUFA: saturated FA ratio. There were no significant differences associated with CP level during the re-alimentation period
Replacement of zinc sulphate by microbial phytase for piglets given a maize-soya-bean meal diet
Authors: Jondrevillea C. , Hayler R. , Feuerstein D.
Published: February 2006

Forty-eight pigs, weaned at 27 days of age at an average body weight of 7·55 kg were used in a 19-day experiment to investigate the influence of microbial phytase on zinc utilization and to calculate equivalency values of zinc as sulphate for microbial phytase. Eight experimental diets were formulated: a maize-soya-bean meal basal diet containing 30 mg of zinc per kg supplemented with 10, 25, 40 or 100 mg of zinc from sulphate (ZnSO4, 7H2O) per kg or with 100, 250, 500 or 750 units (U) of microbial phytase (3- phytase from Aspergillus niger, Natuphos ®) per kg. The dietary supplies of calcium and phosphorus were adjusted accounting for the release of these elements by microbial phytase. The copper concentration in the diets was 11 mg/kg. Pigs were given the basal diet for a 7-day adjustment period prior to the 19-day experimental period. At the end of the experiment, bone ash, phosphorus and calcium concentrations as well as plasma and liver copper concentrations were independent of the diet (P> 0·10). The zinc status of piglets was assessed through plasma alkaline phosphatase activity (APA) and zinc concentration, bone zinc concentration and liver zinc concentration. Plasma zinc, plasma APA and bone zinc increased linearly (P< 0·001) and quadratically (P< 0·01,P< 0·001 andP< 0·001, respectively) with zinc added. These parameters also increased linearly (P< 0·001) and quadratically (P< 0·05,P< 0·001 andP< 0·05, respectively) with phytase added. Liver zinc increased quadratically (P< 0·05) with zinc added and tended to increase linearly with phytase added (P= 0·077). Linear and non-linear response equations of indicators of zinc status to zinc added and phytase added were developed and used to calculate zinc equivalency values of phytase. Non-linear models were linear plateau models for zinc added and exponential models for phytase added. Plasma APA, plasma zinc and bone zinc were maximized when zinc added reached 43, 54 and 56 mg/kg of diet, respectively. The mean function of equivalency of zinc as sulphate (Zn, mg/kg of diet) for microbial phytase (Phyt, U per kg of diet) was Zn = 49·9 − 58·3 e−0·00233Phyt. From this equation it is calculated that 250, 500, and 750 U of 3-phytase from Aspergillus niger can avoid the addition of 17, 32 and 40 mg of zinc as sulphate in a piglet diet. Zinc ingested and, in turn, zinc excreted, may be proportionately reduced by almost 0·30 by replacing 30 mg of zinc as sulphate by 500 U of phytase as Natuphos ® in a piglet maize and soya-bean meal diet formulated to contain 100 mg of zinc per kg.
Effect of variety and preservation method of cassava leaves on diet digestibility by indigenous and improved pigs
Authors: Borin Khieu , Lindberg J. E. , Ogle R. B.
Published: February 2006

Digestibility and nitrogen (N) balance studies were carried out on the leaves of short-term (ST) and long-term (LT) varieties of cassava, preserved by sun-drying and grinding into a meal or by ensiling. The cassava leaf meal and ensiled leaves (471 and 373 g/kg total diet dry matter, respectively) were mixed with palm syrup and palm oil, to give the experimental diets CLM and CLS, respectively. Four Mong Cai (MC) (17·2 (s.e. 2·61) kg) and four Landrace × Yorkshire (L×Y) (41·5 (s.e. 2·12) kg) male castrate pigs were used. The experiment was designed as a 2 × 2 × 2 factorial, with breed, cassava variety and processing method as factors.

The hydrogen cyanide (HCN) levels of the fresh cassava leaves of ST (545 mg/kg dry matter (DM)) and LT (408 mg/kg DM) varieties were reduced by proportionately 0·63 and 0·33, respectively, after sun-drying and by 0·78 and 0·77, respectively, after ensiling. Intake was higher for DM, crude protein (CP) and organic matter (OM) (P < 0·001) and neutral- and aciddetergent fibre (NDF and ADF) and crude fibre (CF) (P <0·01) in CLM than in CLS. There was a breed by processing method interaction for CF intake (P < 0·05). The coefficient of total tract apparent digestibility (CTTAD) was higher in CLS than in CLM for DM, CP, OM and CF (P < 0·001) and NDF and ADF (P < 0·01). The MC pigs digested ADF (P < 0·01) and CF (P < 0·001) more effectively than L×Y pigs but there was no difference (P > 0·05) in the digestibility of other nutrients or DM. There was a breed by cassava variety interaction for ADF digestibility and breed by processing method for CF digestibility (P < 0·01). Daily N intake and faecal N were higher (P < 0·001) in CLM than in CLS. Urinary N was lower in CLS than in CLM (P < 0·05) and in L×Y than in MC pigs (P < 0·001). N utilization (N retained per unit intake) was higher for CLS than CLM (P < 0·001) and in L×Y than in MC pigs (P < 0·001). It is concluded that ensiling is a more effective method than sun-drying for reducing HCN in cassava leaves after 60 days re-growth, and also results in higher digestibility of DM and dietary components than sun-drying. However, the bulkiness of the silage limits intake. The MC pigs digested dietary fibre more efficiently than the L×Y pigs, whereas the L×Y pigs utilized N more efficiently than the MC pigs.
Effect of a high fibre intake on the resistance of the growing rabbit to an experimental inoculation with an enteropathogenic strain ofEscherichia coli
Authors: Gidenne T. , Licois D.
Published: February 2006

Response to an experimental infection with an enteropathogenicE. coliO103 strain (EPEC) was assessed in growing rabbits given a high or a low dietary fibre diet (200 and 120 g acid-detergent fibre per kg respectively for high ‘HF’ or low ‘LF’ fibre diet). The two experimental diets, differing in fibre level but not fibre quality, were given ad libitum from 21 days of age to two groups of 12 litters of nine pups, weaned at 28 days (trial 1) and caged collectively. At 42 days of age, the two groups were divided in two subgroups (i.e. four groups of 18 animals), inoculated or not with an EPEC O103 strain. Two further groups of 48 rabbits (trial 2) were given LF and HF diets from 28 days (weaning) to 70 days, and were individually housed to control precisely the food intake. Reducing the fibre level led to a lower post-weaning food intake (64 v. 85 g/days in the period from 28 to 42 days of age,P< 0·001) and digestible energy intake (0·75v.. 0·86 MJ/day,P< 0·001), causing a lower growth (proportionately 0·088 lower,P< 0·001). At 42 days of age, only 17% of rabbits had a detectable caecal saprophyteE. coliflora (over 102colony-forming units (CFU) per g, trial 1). Inoculating 6-week-old rabbits with EPEC led to moderate levels of mortality (26%). Health risk index (mortality + morbidity) was numerically higher in LF compared with HF groups (P= 0·12). The acute phase of the colibacillosis was between 3 and 10 days post inoculation. From days 7 to 14 post inoculation, a significantly higher frequency of rabbits having a high faecal excretion ofE. coli(> 105CFU per g) was found in LF than in HF rabbits (respectively 65 v. 26·7%,P= 0·04). The caecal pectinolytic flora reached 108CFU per g at 42 and 65 days of age, and was not affected by diet or EPEC challenge. In 42-day-old rabbits the caecal volatile fatty acid concentration was higher in HF than in LF groups (respectively 79 v. 60 mmol/l,P< 0·05), while the caecal pH was slightly lower (respectively 5·93 v. 6·09,P< 0·01). At 65 days of age, rabbits resistant to the inoculation showed a similar fermentation pattern and fibrolytic flora level to non-inoculated animals. Caecal ammonia level was not affected either by age, diet orE. colichallenge (mean = 12·1 mmol/l). From these results, we conclude that a high fibre intake improved the resistance of the growing rabbit to a specific enteropathy, in association with a higher caecal fermentative activity and lower caecal pH.
Incorporating turn-over in whole body protein retention efficiency in cattle and sheep
Authors: Roux C. Z.
Published: February 2006

In pigs the quantification of breakdown and synthesis by powers of body protein led to the estimation of turn-over related protein retention efficiency by the equation kP= {1 + [1 − (P/α)(2/9)Q]−1/6}−1, with α the limit value of whole body protein (P) maturity, so that 0 ≤(P/α)≤1. The factor 2/9 is derived from diffusion attributes indicated by cell and nucleus geometries α and Q represents a scaled transformation of intake, 0 ≤ Q ≤ 1, such that a value of Q = 1 may represent ad libitum intake and Q = 0 the intake at the maintenance requirement. Published observations on finishing steers provide estimates of whole body protein synthesis and breakdown at pre-determined levels of intake in confirmation of the theoretical (2/9)Q power associated with (P/α) inkP. Further confirmation of the (2/9)Q power in cattle follows from satisfactory agreement between an estimate of conventional multiple regression retention efficiency and the turn-over related retention efficiency calculated at the given level of intake, for the mid point of the body mass interval covered by the regression estimate. In addition, a simulation experiment on cattle from the literature gives power estimates of protein breakdown and synthesis in general agreement with those accepted for pigs. Examples on both fine and coarse diets are employed to suggest a general rule for prediction on diets causing submaximal efficiency due to suboptimal intakes.

In sheep, evidence derived from estimates of conventional multiple regression efficiencies suggests that the rule (a-b) = (2/9) Q for the calculation ofkPshould be reserved for the description of compensatory growth. Protein retention efficiency for ordinary growth should be described by an adaptation of the rule derived for suboptimal intakes.
Tolerance of imported rabbits grown as meat animals to hot climate and saline drinking water in the subtropical environment of Egypt
Authors: Marai I. F. M. , Habeeb A. A. M. , Gad A. E.
Published: February 2006

Ninety of each of New Zealand White (NZW) and Californian (Cal) male weaned rabbits at 5 weeks of age with nearly similar average live weights were used during two periods of the year (mild and hot, each of 9 weeks), in a trial to evaluate their adaptability as meat animals to the subtropical conditions of Egypt. The results showed that NZW surpassed Cal, in most of the traits studied. The increase was significant in final live weight, daily weight gain, final body solids, daily body solids gain, body water concentration (ml per 100 g body solids) and pre-slaughter weight. Meanwhile, Cal significantly surpassed NZW in daily water consumption. The temperature-humidity index (THI) values indicated absence of heat stress in the first period and exposure to moderate (but very close to severe) heat stress in the second. The hot conditions induced significant decline in final live weight, daily weight gain, food intake, final body solids, daily body solids gain, plasma tri-iodothyronine (T3) hormone, total proteins, albumin, globulin, total lipids, glucose, electrolytes (Na, K, Ca, Mg and P), pre-slaughter weight and kidneys with fat weight. In contrast, the hot conditions were accompanied by significant increases in water intake, body water concentration, plasma urea-N, creatinine and physiological body reactions (respiration rate and temperatures of rectum, skin and ear). Drinking water containing high levels of salt (3000 p. p. m. and more) caused significant decreases in final live weight, daily live-weight gain, final body solids, daily body solids gain, plasma T3 hormone, total proteins, albumin, total lipids, glucose, pre-slaughter weight and kidneys with fat weight. At the same time, significant increases occurred in water consumption, body water concentration, plasma urea-N, creatinine, electrolytes (Na, K, Ca and P), respiration rate and rectal and skin temperatures. Estimations of adaptability to the subtropical environment of Egypt and tolerance to drinking saline water under the same conditions were found to be proportionately 0·844 and 0·876 and 0·821 and 0·803, in NZW and Cal, respectively.
Ileal digestibility of raw and autoclaved kidney-bean (Phaseolus vulgaris) seed meals in cannulated pigs
Authors: Rubio L. A.
Published: February 2006

Five castrated male pigs (100±2 kg mean live weight) fitted with T-shaped ileal cannulae were used to determine ileal digestibility of raw or autoclaved (136°C, 3 min, 2·3 bar) kidney-bean seed meals, which were included (536 g/kg) in the diet as the only protein source. A protein-free and a diet based on hydrolysed casein were used to estimate endogenous protein secretion. Apparent ileal digestibility of dry matter was lower (P < 0·05) for raw compared to autoclaved kidney-bean meal. Apparent and true ileal digestibilities of raw kidney-bean meal were not only lower (P < 0·05) than those of autoclaved kidney beans, but negative or close to zero for N and some amino acids. Ileal N (36·9 g/kg food ingested) and sialic acid (3·5 g/kg food ingested) flows in pigs given the raw kidney-bean-based diet were higher (P < 0·05) than those of pigs given the autoclaved kidney-bean diet (respectively 8·9 and 1·4 g/kg food ingested). Autoclaved kidney beans contained 364 and 143 g/kg of starch and non-starch polysaccharides respectively, the ileal digestibilities of which were 0·79 and 0·26. Among individual non-starch polysaccharide sugars, apparent ileal digestibility values were between 0 (rhamnose) and 0·38 (arabinose). Ileal apparent digestibility of total oligosaccharides in the autoclaved kidney bean diet was 0·52, and total amounts of oligosaccharides digested was 18·6 g/kg food. Among individual short-chain fatty acids in ileal contents, only propionate values were signifi cantly (P < 0·05) different between pigs given raw or autoclaved kidney-bean diets. Lactate concentration in ileal contents was higher (P < 0·05) in pigs given autoclaved compared with raw kidney beans. Ileal digestibility of autoclaved kidney-bean meal in the 10-kg pigs was poorer than that of other raw legume-seed meals such as lupins and chickpeas in other studies. The potential health implications of these results are also discussed.
Estimation of roughage intake in sheep using a known daily intake of a labelled supplement
Authors: Elwert C. , Dove H.
Published: February 2006

A feeding trial with growing sheep was conducted on mixed roughage-supplement diets, to test whether roughage intake could be estimated from a known intake of a supplement and an alkane-based estimate of the supplement and roughage proportions in the diet (diet composition) without the need for separate dosing with external marker alkanes. Diets consisted of chaffed Trifolium subterraneum hay (SC), or a mix of SC and beeswax-labelled cottonseed meal (CSM) in the proportions of 7: 1, 6: 2, 5: 3 and 4: 4 (air-dry matter basis). Six sheep were given the pure SC diet and three sheep were given each of the mixed diets. Additionally, the CSM was also labelled with octatriacontane (C38) to investigate its use for labelling supplements. Due to unexpectedly low recoveries, C38 was not included in any estimation of diet composition or digestibility.

The inclusion of beeswax-labelled CSM in a SC diet resulted in lower faecal alkane recoveries (as proportions of alkane ingested; P ≤ 0·05). Within mixed diets, recoveries decreased significantly with increasing proportion of CSM, but this effect was significant (P < 0·05) only for alkanes consisting of 25, 26, 27 and 29 carbon-atoms. Estimates of diet composition were close to measured values. Daily SC intake and organic matter digestibility (OMD) differed by −3·7 to 7·2% and −2·0 to 5·7% from measured values if a mean faecal recovery, across diets, was applied for each alkane. Accuracy increased greatly if estimates were based upon faecal alkane recoveries for individual diets, instead of mean recoveries across diets (−0·3 to 0·9% and −0·2 to 0·0% for SC intake and OMD, respectively).

The results indicate that roughage intake can be estimated from a combination of known supplement intake and an estimate of diet composition, which obviates the need for separate alkane dosing to estimate intake. The method should be applicable in situations in which animals either normally receive supplements (e.g., dairy cows) or could readily be given supplements.
In vitromicrobial growth and rumen fermentation of different substrates as affected by the addition of disodium malate
Authors: Tejido M. L. , Ranilla M. J. , García-Martínez R. , Carro M. D.
Published: February 2006

The effects of two concentrations of disodium malate on thein vitrofermentation of three substrates differing in their forage: concentrate ratio (0·8: 0·2, 0·5: 0·5 and 0·2: 0·8; g/g dry matter; low-, medium- and high-concentrate substrates, respectively) by rumen micro-organisms were studied using batch cultures. Rumen contents were collected from four Merino sheep offered lucerne hay ad libitum and supplemented daily with 400 g concentrate. Disodium malate was added to the incubation bottles to achieve final concentrations of 0, 4 and 8 mmol/l malate and15N was used as a microbial marker. Gas production was measured at regular intervals from 0 to 120 h of incubation to study fermentation kinetics. When gas production values were corrected for gas released from added malate, no effects (P> 0·05) of malate were detected for any of the estimated gas production parameters. In 17-h incubations, the final pH and total volatile fatty acid (VFA) production were increased (P< 0·001) by the addition of malate, but no changes (P> 0·05) were detected in the final amounts of ammonia-N and lactate. When net VFA productions were corrected for the amount of VFA produced from malate fermentation itself, adding malate did not affect (P> 0·05) the production of acetate, propionate and total VFA. Malate reduced methane (CH4) production by proportionately 0·058, 0·013 and 0·054 for the low-, medium- and high-concentrate substrates, respectively. Adding malate to batch cultures increased (P< 0·01) rumen microbial growth (mean values of 16·6, 18·3 and 18·4 mg of microbial N for malate at 0, 4 and 8 mmol/l, respectively), but did not affect (P> 0·05) its efficiency of growth (55·5, 56·7 and 54·3 mg of microbial N per g of organic matter apparently fermented for malate at 0, 4 and 8 mmol/l, respectively). There were no interactions (P> 0·05) malate × substrate for any of the measured variables, and no differences (P> 0·05) in pH, CH4production and microbial growth were found between malate at 4 and 8 mmol/l. The results indicate that malate had a beneficial effect on in vitro rumen fermentation of substrates by increasing VFA production and microbial growth, and that only subtle differences in the effects of malate were observed between substrates. Most of the observed effects, however, seem to be due to fermentation of malate itself.
Apparent ileal digestibility of amino acids in dietary ingredients for broiler chickens
Authors: Ravindran V. , Hew L. I. , Ravindran G. , Bryden W. L.
Published: February 2006

The apparent ileal digestibility coefficients of amino acids in 107 samples representing 22 food ingredients were determined using 6-week-old broiler chickens. The ingredients assayed included five cereals (barley, maize, sorghum, triticale and wheat), two cereal by-products (rice polishings and wheat middlings), four oilseed meals (canola, cottonseed, soya-bean and sunflower meals), full-fat canola, maize gluten meal, four grain legumes (chickpeas, faba beans, field peas and lupins) and five animal protein sources (blood, feather, fish, meat and meat and bone meals). The mean ileal digestibility coefficients of amino acids in wheat and maize were higher than those in sorghum, triticale and barley. However, variations observed in individual amino acid digestibilities among samples within cereal type were greater than those determined between cereals. Threonine and lysine were the least digestible indispensable amino acids in the five cereals evaluated. The most digestible indispensable amino acid was phenylalanine in wheat and, leucine in maize and sorghum. In the case of the wheat middlings and rice polishings, threonine was the least digestible indispensable amino acid and arginine was the best digested.

In the oilseed meals assayed, amino acid digestibility was highest for soya-bean and sunflower meals, intermediate for canola meal and lowest for cottonseed meal. Ileal digestibility coefficients of amino acids in lupins were found to be slightly lower than those in soya-bean meal. The amino acid digestibilities of field peas, faba beans and chickpeas were considerably lower than those of lupins. Digestibility of arginine was the highest and that of threonine was the lowest of the indispensable amino acids in oilseed meals and grain legumes, except in cottonseed meal. Lysine was the least digestible amino acid in cottonseed meal.

In the animal protein sources assayed, digestibility coefficients of amino acids in blood meal were high, intermediate in fish meal, and low in meat meal, meat and bone meal and feather meal. Variation in amino acid digestibility coefficients determined for blood meal samples was small. However, wide variations in amino acid digestibilities were observed for other animal protein sources, highlighting significant batch-to-batch differences. In particular, marked variations were determined for meat meal and meat and bone meal samples. Cystine was the least digested amino acid in animal protein meals, with the exception of blood meal in which isoleucine had the lowest digestibility. The limitations of using apparent digestibility values in diet formulations and the concept of the standardized digestibility system to overcome these limitations are discussed.
Characteristics of cattle movements in Britain – an analysis of records from the Cattle Tracing System
Authors: Mitchell A. , Bourn D. , Mawdsley J. , Wint W. , Clifton-Hadley R. , Gilbert M.
Published: February 2006

This paper reviews the main temporal and spatial characteristics of cattle movements in Britain, based on an analysis of records in the British Cattle Movement Service's Cattle Tracing System (CTS) database, focusing on the period 2001 to 2003, during which notification of cattle movements was mandatory. Movements vary weekly and seasonally according to the production cycle, with peaks in late spring (April) and early autumn (October), and an average 1·63 million farm-to-farm movements per month, equivalent to 19·6 million per annum. The geographical distribution of these movements appears to be relatively stable from year to year, with the great majority of animals moving less than 100 km per journey, although many tens of thousands move over far greater distances of up to 1000 km. The procedures developed to extract, match, geo-reference, analyse and display movement records have greatly enhanced the utility of the CTS database, in that it is now feasible to assess, monitor and mapthe spatial dynamics and geographical distribution of cattle movements, and provide this information in standardized format on a regular basis.
Population parameter estimation of daily milk yield of the Chios sheep using test-day random regression models and Gibbs sampling
Authors: Banos G. , Arsenos G. , Abas Z. , Basdagianni Z.
Published: February 2006

Parameters of daily milk yield during the first three lactations of Chios ewes were estimated with random regression models. Data consisted of 42 675 test-day records of 7121 ewes from 75 flocks that had lambed between 1998 and 2000. Models fitted fourth order fixed regressions on Legendre polynomials of the number of days post partum and fourth order random regressions on the individual animal. (Co)variance components were estimated with Gibbs sampling. Lactations were analysed separately. The four eigen values accounted for 0·80 to 0·84, 0·11 to 0·15, 0·04 to 0·05 and about 0·01 of the animal variance, respectively, depending on lactation number. Animal variance estimates, including genetic and, partly, permanent environment effects, were high at the beginning of each lactation and decreased as lactation progressed, suggesting that the animal effect is most important to early daily records. Residual variance was highest in the middle of lactation, suggesting that non-systematic environmental factors play a bigger at that time. Animal correlation estimates between daily yield records ranged from 0·26 to 0·99, were highest for adjacent days and decreased for days further apart. The decline had a different shape in the three lactations and was more evident in the first, suggesting that the three lactations may be biologically distinct traits. Animal correlation estimates between daily and total lactation milk yield ranged from 0·61 to 0·98 and were highest in the middle and lowest towards the end of lactation. Early lactation daily yield had an animal correlation of 0·70 to 0·80 with total lactation milk yield, in all three lactations. Results of this study suggest that daily milk yield records in the early stages of lactation may be useful for selection of ewes with high producing ability and accurate prediction of total lactation milk yield.
Biochemical differences in Merino sheep selected for resistance against gastro-intestinal nematodes and genetic and nutritional effects on faecal worm egg output
Authors: Liu S. M. , Smith T. L. , Palmer D. G. , Karlsson L. J. E. , Besier R. B. , Greeff J. C.
Published: February 2006

The faecal egg count (FEC) and total egg output is reduced in parasite-resistant sheep and breeding sheep for resistance should reduce infective larval contamination of pastures. This research compares lambs and rams from the parasite-resistant flock, Rylington Merinos, with unselected controls at the same level of larval challenge and the same level of food supply in an animal-house environment. The sheep were penned individually. The parasite resistant sheep excreted 0·85-fold less eggs than the control animals after infection with Trichostrongylus colubriformis and Ostertagia circumcincta for 12 or 18 weeks. During the infection period the parasite resistant lambs had higher plasma immunoglobulin concentration and higher ratio of globulin to albumin than the control animals. In the mature rams these genotype differences diminished. They also had lighter mass of the small intestine with a higher proportion of mucosa, but heavier mass of the large intestine. Parasite infection caused a depletion of blood glutathione in the lambs given food at maintenance or 1·5 × maintenance, and the parasite-resistant sheep (both lambs and rams) also had lower glutathione concentration. Maintaining good body nutrient reserve before the infection reduced the egg output in the early stage of the infection. Food intake had little effect on worm egg production in young sheep given food at maintenance or above. It is suggested that an improvement of nutrition, sulphur-containing amino acids in particular, is required to recover the loss of productive performance caused by the infection.
Associations of acute phase protein levels with growth performance and with selection for growth performance in Large White pigs
Authors: Clapperton M. , Bishop S. C. , Cameron N. D. , Glass E. J.
Published: February 2006

Abstract Acute phase proteins (APP) are released into the circulation in mammals upon infection and may be used to diagnose the health status of managed populations of animals such as pigs. The current study determines APP levels in a population of apparently healthy Large White pigs from a single farm, to address two questions: (1) whether phenotypic associations can be observed between productivity and APP, indicating the effects of possible subclinical infections and (2) whether previous selection for either food intake or ‘lean growth under restricted feeding’ influences APP levels. The APP investigated were alpha1- acid glycoprotein (AGP) and haptoglobin. The APP were measured at 18 and 24 weeks of age in pigs previously selected for high lean growth (no. = 31), low lean growth (no. = 38), high daily food intake (no. = 24) and low daily food intake (no. = 26), but performing under ad libitum feeding conditions. Performance traits and APP levels were constant over the experimental period, indicating that the farm health status did not vary over time. Performance traits and APP were recorded on 119 pigs, of which 80 had both APP and performance measurements. Multiple regression analyses were used to investigate phenotypic relationships between performance traits and APP levels. Plasma concentrations of AGP were higher in 18-week-old pigs compared with 24-week-old pigs (P< 0·01) whereas haptoglobin levels did not vary according to age. Significant sex differences in APP levels were observed. Females had higher circulating levels of AGP than males at both 18 weeks and 24 weeks. Females also had higher levels of haptoglobin at 18 weeks. Levels of AGP had significant negative correlations with daily weight gain (−0·59,P< 0·01 and −0·48,P< 0·05 at 18 and 24 weeks respectively) and with daily food intake (−0·53,P< 0·01 and −0·38,P< 0·05 at 18 and 24 weeks respectively). At age 24 weeks, haptoglobin was negatively correlated with both daily weight gain (−0·35,P< 0·05) and food efficiency (−0·34,P< 0·05). Pigs selected for high lean growth under restricted feeding had higher AGP levels than pigs selected for low lean growth under restricted feeding at 18 (593v. 332 μg/ml,P< 0·01) and 24 weeks of age (313 v. 219 μg/ml,P< 0·05). Selection for daily food intake did not consistently affect AGP levels, and neither selection criteria influenced plasma haptoglobin concentrations. To conclude, we have demonstrated that amongst contemporaneous pigs of the same genotype, higher systemic AGP levels and, to a lesser extent, higher haptoglobin levels are associated with decreased performance, and that genetic selection for ‘efficient lean growth under restricted feeding’ can increase serum AGP levels.
Development of a maternal breeding goal and tools to select for this goal in UK beef production
Authors: Roughsedge T. , Amer P. R. , Thompson R. , Simm G.
Published: February 2006

A maternal breeding goal for the UK beef industry is described and economic selection indexes are developed to assist in the selection of animals for the goal. The breeding objective is made up of general maternal ability traits, cow size, calving and carcass traits. The general maternal ability traits include calving interval, age at first calving, lifespan, maternal weaning weight and maternal calving difficulty. The calculations of economic values for the traits are outlined and discounted genetic expression coefficients are presented. Three selection indexes are illustrated. The first provides a general dualpurpose index for the selection of bulls to produce replacement heifers in most situations. The second, the hardy breed index, is designed to allow selection for improved maternal performance in extensive and hardy environments. The third, the fertile herd index, allows producers who do not have herd fertility problems to place more selection emphasis on objectives other than fertility. A sample of data from the Limousin breed was used to calculate estimated breeding values (EBVs) which were used to investigate response to the three indexes when the top 20% of sires were selected from either sires with 50 or more grand-maternal progeny or bulls with no recorded progeny. Approximately two thirds of the economic response seen in the selection of heavily used bulls was observed in bulls with no progeny for the hardy and dual-purpose indexes. Bulls were also selected using the existing UK terminal sire index and the resulting bulls assessed in the dual-purpose maternal index. There was found to be a negative economic response to the maternal aspect of the index, though a positive response was seen in the carcass objective. The indexes are presented as the sum of four subindexes emphasizing the contribution of maternal ability, cow size, calving and carcass, respectively to the total index. This further assists commercial producers in selection decisions.
Reproductive rhythm and litter weaning age as they affect rabbit doe performance and body energy balance
Authors: Xiccato G. , Trocino A. , Boiti C. , Brecchia G.
Published: February 2006

Abstract One hundred and twenty multiparous does were synchronized to give birth the same day (initial kindling). The trial lasted until the successive (final) kindling. Immediately following initial kindling, 22 does were selected for comparative slaughter. The remaining does were assigned to three reproductive rhythms and mated 2 (R2), 11 (R11) or 26 (R26) days post partum. Within each rhythm, the does were further divided into two groups with litters weaned at 21 (W21) or 25 (W25) days of age. A total of 54 does were pregnant and were slaughtered soon after final kindling. By increasing the kindling-to-mating interval from 2 to 26 days, total milk production was increased (5590 to 6065 g for R2 and R26, respectively;P< 0·05); voluntary food intake during lactation was not affected (356 g/day on average), but during the dry period was reduced (182 to 169 g/day;P< 0·05) in this way accounting for a decrease during the experimental period on the whole (299 to 249 g/day;P< 0·01). At the final kindling, the number of kits born per litter was lower in does submitted to the R11 than to the R26 rhythm (P< 0·01). By increasing the kindling-to-mating interval, doe body water concentration decreased, while fat and energy increased (P< 0·01) and higher empty body gain was recorded (from −123 to −4, and to +97 g, in R2, R11 and R26 does, respectively;P< 0·001). As a result, body protein, fat and energy balances changed from negative values to approach equilibrium as reproductive rhythm became extensive (energy balance: −0·14, −0·02 and +0·01 of the initial body content in R2, R11 and R26 does, respectively;P< 0·001). At 28 days after kindling, blood leptin concentration was higher (P< 0·01) and IGF-1 lower (P< 0·05) in R26 does. Daily food intake throughout the experiment was lower (P< 0·05) in W21 does due to the longer dry period. Increasing weaning age from 21 to 25 days increased both number of kits born alive per litter (from 7·4 to 9·6;P< 0·05) and doe body water concentration, while body energy tended to decrease (P< 0·1). At 28 days after kindling lower blood leptin concentration was recorded in W21 than W25 does (1·87 v. 2·76 μg/l,P< 0·05).
Effects of ensiled forage legumes on performance of twin-bearing ewes and their progeny
Authors: Speijers M. H. M. , Fraser M. D. , Haresign W. , Theobald V. J. , Moorby J. M.
Published: February 2006

Twenty-four twin-bearing mature Mule ewes were used to evaluate the effects of feeding ensiled red clover (Trifolium pratense), lucerne (Medicago sativa) or perennial ryegrass (Lolium perenne) during late pregnancy on subsequent ewe and lamb performance. Eight weeks prior to lambing the ewes were individually penned and offered one of the treatment forages ad libitum (no. = 8 per silage). All ewes were supplemented with molassed sugar-beet shreds to avoid dietary energy being a limiting factor and to ensure the responses were primarily attributable to the forage protein content. Individual intakes of the ewes were determined daily and weekly measurements of ewe live weight and body condition score were made. The ewes were also scanned weekly for depths of subcutaneous fat and longissimus dorsi (LD) muscle. Blood samples were taken at 6, 4, 2, and 1 week(s) before lambing, 24 h after lambing and at 3 weeks after lambing and were analysed for serum concentrations of total protein (TP), albumin, urea, beta-hydroxybutyrate (BHB) and plasma concentrations of glucose and non-esterified fatty acid (NEFA). After lambing all ewes and their lambs were turned out to graze together on a ryegrass sward. The lambs were weighed at birth and at weekly intervals thereafter until 12 weeks post partum. The lucerne silage offered had a higher dry matter (DM) content than the red clover and ryegrass silages (367, 305 and 314 g DM per kg fresh matter, respectively;P< 0·001). Forage type significantly affected crude protein (CP) concentration (240, 215 and 182 g CP per kg DM for lucerne, red clover and ryegrass silages, respectively) and metabolizable energy (ME) density (11·1, 11·6 and 10·8 MJ ME per kg DM respectively). Ewes offered the legume silages had higher intakes of DM, CP and ME than ewes offered ryegrass silage (P< 0·05), which was reflected in higher ewe live-weight gain (P< 0·05) but not in litter birth weight (P> 0·05). Silage treatment affected serum concentrations of TP, albumin, globulins and urea during the last 4 weeks of pregnancy (P< 0·05). Lambs born from ewes offered lucerne and red clover silages prior to lambing had higher growth rates from birth to 3 weeks of age than those from ewes offered ryegrass silage (320, 323 and 282 g/day, respectively;P< 0·05). Lamb live weight at 12 weeks of age was higher for lambs from ewes that had been offered the red clover silage, at 29·1 kg compared with 26·7 and 27·1 kg for lambs from ewes previously offered lucerne and ryegrass silages (P< 0·05). In conclusion, the results showed that red clover and lucerne silages are better able to meet nutrient requirements of ewes in late pregnancy than grass silage.
The influence of livestock management on habitat quality for farmland birds
Authors: Buckingham D. L. , Peach W. J.
Published: February 2006

Abstract This review covers research linking foraging habitat quality for birds to livestock management in lowland farmland. Based on this research we propose a framework for predicting the value of grazing systems to birds. This predictive framework is needed to guide the development of agri-environment measures to address farmland bird declines in pastoral areas. We show that the exacting requirements of declining granivorous birds pose the greatest challenges, while the needs of soil invertebrate feeding species are more easily met.
Impact of grazing management on biodiversity of grasslands
Authors: Tallowin J. R. B. , Rook A. J. , Rutter S. M.
Published: February 2006

This paper reviews recent work carried out by the Institute of Grassland and Environmental Research and collaborating organizations that addresses some of the impacts of grazing management on both species-rich and species-poor lowland neutral grassland. Results indicate that for species-rich grassland, lenient grazing pressure maintained botanical diversity and the abundance of positive indicator species of nature conservation value over a 5-year period and also enhanced faunal diversity and abundance reflecting improvements in spatial, architectural and temporal structure. However, there was no enhancement in positive indicator species and there was also an increase in pernicious weeds suggesting that grazing alone may not suffice to deliver all the biodiversity goals for these grasslands and that additional management interventions may be required. For species-poor grassland, results indicate that distinctive differences in structure can lead to differences in faunal diversity. There is also some tentative evidence that livestock breed may affect invertebrate species assemblages.
How do the nature of forages and pasture diversity influence the sensory quality of dairy livestock products?
Authors: Martin B. , Verdier-Metz I. , Buchin S. , Hurtaud C. , Coulon J. -B.
Published: February 2006

Abstract This review summarizes the recent developments in understanding of the relationships between the diet of animals and the sensory quality of dairy products. Feeding dairy cattle with maize silage by comparison with hay or grass silage leads to whiter and firmer cheeses and butter and sometimes to differences in flavour. Major differences in sensory characteristics were observed between cheeses made with milk produced by cows on winter diets (based on hay and grass silage) or turned out to pasture in the spring. Conversely, preserving grass as silage, by comparison with hay, has no major effect on cheese sensory characteristics, except on colour, the cheese being yellower with grass silage. Several recent experiments have shown a significant effect of grass botanical composition on cheese texture and flavour. These effects are due to the presence in milk of specific molecules directly introduced by feeding (carotenes, terpenes) or produced by the animals (plasmin, fatty acids) under the effect of specific diets.
Profiles of Self‐Reported HIV‐Risk Behaviors Among Injection Drug Users in Methadone Maintenance Treatment, Detoxification, and Needle Exchange Programs
Authors: Mark Hayley Diana , Nanda Joy , Davis‐Vogel Annet , Navaline Helen , Scotti Roseanne , Wickrema Rasanjali , Metzger David , Sochalski Julie
Published: February 2006

ABSTRACT 
Objective:
Injection drug use has accounted for more than one third of acquired immune deficiency syndrome cases in the United States. The purpose of this study was to compare the demographic characteristics, types, and frequency of human immunodeficiency virus (HIV)‐risk behaviors among injection drug users (IDUs) recruited from a needle exchange program (NEP), methadone maintenance treatment (MMT), and detoxification (detox) program. Design: A cross‐sectional, correlational design was used to determine whether the selected HIV‐risk behaviors and demographic characteristics of IDUs varied by site of recruitment. Sample and Measurements: Confidential questionnaires were completed by 445 IDUs in Philadelphia, Pennsylvania. Results: Data analysis revealed that HIV sexual and injection‐risk behavior varied by recruitment site. Subjects recruited from the NEP were more likely to engage in HIV‐risk behaviors than subjects recruited from the MMT or detox sites. Conclusions: Interventions occurring in program and treatment sites need to be sensitive to various demographic characteristics and behaviors if they are to reach those at highest risk of HIV infection. Targeting HIV prevention interventions based upon risk group membership alone (e.g. IDUs) fails to address the distinct risk behaviors and demographic characteristics of enrollees in different programs.
A Qualitative Approach to Understanding Patients' Diagnosis of Lyme Disease
Authors: Drew Debra , Hewitt Hilary
Published: February 2006

ABSTRACT 
Objectives:
The purpose of this study was to explore the lived experience of becoming diagnosed with Lyme disease. Design: A qualitative, phenomenological study was conducted to investigate the experience of becoming diagnosed with Lyme disease.Sample: A purposive sample of 10 participants diagnosed with Lyme disease were interviewed and tape‐recorded. Data saturation guided the size of the sample. Methods: The interviews were transcribed verbatim. Key words or phrases were extracted and clustered; clusters were interpreted into themes. Analyzed data were confirmed with the participants for trustworthiness and reliability. Results: Six themes emerged from the interviews. Participants expressed feelings of frustration during the long road to diagnosis. They endured multiple diagnostic tests and were seen by numerous health care providers. Participants voiced financial stress. They expressed the need for self‐advocacy and felt validation when a diagnosis was made. Despite the chronicity of their illness, the participants voiced a sense of hopefulness for their future. Conclusion: A deep understanding of the lived experience of becoming diagnosed with Lyme disease allows for nurses to prioritize health care interventions and strategize ways to implement quality improvement systems as clients enter the health care environment.
Talking Circles: Northern Plains Tribes American Indian Women's Views of Cancer as a Health Issue
Authors: Becker Sara A. , Affonso Dyanne D. , Beard Madonna Blue Horse
Published: February 2006

ABSTRACT 
Objective:
The purpose of this research was to understand the cultural meanings of cancer among American Indian women from Northern Plains tribes living in western South Dakota and their experiential view of breast and cervical cancer screening. Design and Sample: Using an exploratory design, a purposive sample of 28 women, 35–75 years of age, were recruited into three Talking Circles. Measurement: Talking Circle and focus group methodology, combined with Affonso's Focus Groups Analytic Schema, were used to generate contextual data sets including thematic findings. Results: Ten themes emerged indicating interrelationships between cultural traditions and health structures of care. The themes provided a unique perspective for conceptualizing women's experiences with breast and cervical cancer screening. Conclusions: Incorporating women's cultural experiences into screening services is necessary to address clinical and policy challenges for reducing breast and cervical cancer mortality among American Indian women. Findings from this research will be used to guide a future study investigating breast‐screening patterns related to mammography adherence and development of interventions specific to American Indian women.