bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of forage conservation method, concentrate level and propylene glycol on intake, feeding behaviour and milk production of dairy cows
Authors: Shingfield K. J. , Jaakkola S. , Huhtanen P.
Published: August 2016

The current study was conducted to establish if effects on animal performance due to differences in forage composition resulting from conservation method could be compensated for by increases in concentrate feeding or supplements of a gluconeogenic substrate. Thirty-two Finnish Ayrshire dairy cows were used in a cyclic changeover experiment with four 21-day experimental periods and a 4 ✕ 2 ✕ 2 factorial arrangement of treatments to evaluate the effects of forage conservation method, concentrate level and propylene glycol (PG), and their interactions, on intake, feeding behaviour and milk production. Experimental treatments consisted of four conserved forages offered ad libitum, supplemented with two levels of a cereal-based concentrate (7 or 10 kg/day) and PG (0 and 210 g/day) offered as three meals of equal size. Forages were prepared from primary growths of timothy and meadow fescue swards and ensiled using no additive (NA), an inoculant enzyme preparation (IE) or a formic-acid based (FA) additive or conserved as hay 1 week later. Cows given silage-based diets had higher (P 0·001) forage dry-matter (DM) intakes (mean increase 0·76 kg/day), spent less (P 0·001) time eating and chewing (mean response -159 and -119 min/day, respectively) and produced more (P 0·05) energy-corrected milk (ECM), milk fat and milk lactose (respective mean responses 1·52, 0·098 and 0·033 kg/day) than animals given hay-based diets. Use of an additive during ensiling further improved (P 0·05) silage DM intake, ECM yield and milk protein secretion (mean 0.72, 0.70 and 0.038 kg/day, respectively). Dietary inclusion of PG decreased forage DM intake for hay, IE and FA silage-based diets (mean –0·14, –0·16 and –0·42 kg/day, respectively) but elicited positive responses (mean 0·57 kg/day) for cows given NA silage. Furthermore, PG supplementation had no (P > 0·05) effects on ECM yield or milk protein output but depressed (P 0·05) mean milk fat content from 46·6 to 45·6 g/kg. Increases in concentrate feeding were associated with a reduction in the total amount of time cows spent eating, chewing and ruminating and elicited (P 0·001) mean DM intake, ECM yield, milk fat and milk protein responses of 1·5, 1·62, 0·061 and 0·064 kg/day, respectively. Use of a gluconeogenic substrate or increases in concentrate feeding were unable to compensate for variations in animal performance due to forage conservation method.
Calves sucking colostrum and milk from their dams or from an automatic feeding station starting in the neonatal period: metabolic and endocrine traits and growth performance
Authors: Schiessler G. , Nussbaum A. , Hammon H. M. , Blum J. W.
Published: August 2016

Metabolic and endocrine traits and growth performance from birth up to day 28 in calves sucking colostrum and milk at a computer-programmed automatic feeding station (GrA, no. = 7) were compared with calves sucking their dams (GrS, no. = 7). Body weight tended to be higher on day 28 in GrS than in GrA (74 (s.e. 4) and 70 (s.e. 2) kg, respectively; P 0·1), but not weight gain from 0 to 28 days. Intakes in GrA increased from days 1 to 4 and then remained at 11·1 (s.e. 1·0) l/day. From days 2 to 11 calves visited the automatic feeding station 9 (s.e. 1) times per day. Plasma concentrations of urea (days 3 and 21), glucagon (day 3) and growth hormone (day 3) were higher in GrA than in GrS (P < 0·05), whereas plasma concentrations of total protein (days 1 to 28), immunoglobulin G (days 1 to 28), albumin (days 1 to 14), glucose (day 3), lactate (days 1 and 28), triglycerides (day 3), cholesterol (days 21 and 28), insulin (day 3), and insulin-like growth factor-1 (day 21) were lower in GrA than in GrS (P < 0·05). Metabolic and endocrine group differences were mainly seen in week 1. However, growth performance during the first 3 weeks of life was comparable in calves of the two groups but resulted in slightly enhanced body weight (by 4 ± 3·5 kg) at the end of the 1st month of life in GrS.
Visible/near infrared reflectance spectroscopy for predicting composition and tracing system of production of beef muscle
Authors: Cozzolino D. , Mattos D. De , Martins D. Vaz
Published: August 2016

Muscle chemical analysis and muscle identification both were attempted by using visible and near infrared reflectance spectroscopy (NIRS). Seventy-eight beef muscles (m. longissimus dorsi) from Hereford cattle were used. The samples were scanned in a NIRS monochromator instrument (NIRSystems 6500, Silver Spring, MD, USA) in reflectance mode (log 1/R). Both intact and minced muscle presentation to the instrument were explored. Predictive equations were made using ISI software (Infrasoft International, Port Matilda, PA, USA) and muscle identification was performed by Principal Component Analysis (PCA) and Soft Independent Modelling of Class Analogy (SIMCA). The coefficient of determination in calibration (R2CAL) and standard error in cross validation (SECV) for the intact sample presentation were 009 (SECV: 15·6), 0·89 (SECV: 46·9), 0·48 (SECV: 23·9) for moisture (M), fat and crude protein (CP) on g/kg fresh weight basis respectively. R2CAL and SECV for minced sample presentation were 0·41 (SECV: 161), 0·92 (SECV: 43·4), 0·71 (SECV: 20·5) for M, fat and CP on g/kg fresh weight basis respectively. Qualitative analysis of optical information through PCA and SIMCA analysis showed differences in muscles resulting from two different feeding systems.
Effect of rumen degradable protein with or without fermentable carbohydrate supplementation on blood metabolites and embryo survival in cattle
Authors: Kenny D. A. , Boland M. P. , Diskin M. G. , Sreenan J. M.
Published: August 2016

High intakes of dietary protein, particularly rumen degradable protein (RDP), lead to elevations in systemic concentrations of ammonia and (or) urea and these may be increased further if associated with inadequate fermentable energy intake. High systemic concentrations of ammonia and urea have been associated with reduced reproductive performance in cattle. The objective of this study was to examine the effect of RDP and fermentable energy intake on a range of blood metabolites and on embryo survival in heifers.
Oestrous synchronized, nulliparous beef heifers (no. = 162) were randomly assigned in a 2 ✕ 2 factorial designed experiment to two levels of RDP and two levels of fermentable energy. Grass silage-based diets were supplemented with either 0 (0U) or 240 (240U) g dietary urea (460 g/kg N) and these in turn with either 0 (0P) or 3 (3P) kg dry matter of molassed sugar-beet pulp pellets (MSBP) per day. The four treatments were, therefore, (1) 0U + 0P (no. = 43), (2) 0U + 3P (no. = 44), (3) 240U + 0P (no. = 40) (4) 240U + 3P (no. = 35), respectively. Systemic concentrations of ammonia, urea, insulin, glucose and progesterone were measured. Heifers were given artificial insemination (AI) and embryo survival measured by ultrasonography at 30 and again at 40 days after AI.
Systemic ammonia and urea were elevated (P < 0·001) in the animals given the high RDP diets. Supplementation with MSBP reduced systemic urea in the heifers on both high and low RDP diets. Plasma ammonia concentrations were not affected by MSBP supplementation (P > 0·05). Plasma glucose was not affected by urea or MSBP treatment (P > 0·05) but was affected by day and time of sampling (P > 0·05). Plasma concentration of insulin was not affected by urea or MSBP supplementation or by day or time of sampling (P > 0·05). Plasma concentration of progesterone was not affected by diet or time of sampling (P > 0·05). The overall embryo survival rate was 62% and was not affected by dietary urea or fermentable carbohydrate or by systemic concentrations of ammonia, urea, glucose, insulin or progesterone (P > 0·05).
Prediction of carcass lean content by real-time ultrasound in Pietrain and negative stress Pietrain
Authors: Youssao I.A.K. , Verleyen V. , Leroy P.L.
Published: August 2016

Real-time ultrasound data of backfat thickness, longissimus muscle depth and longissimus area were carried out on 335 pigs (164 gilts and 171 barrows) using the Pie Medical Scanner 200 equipped with an ASP-18 probe and 3·5 MHz to predict carcass lean content in positive stress Pietrain (TT) and negative stress Pietrain (CC or CT). They were given food ad libitum and slaughtered at an average age of 213 days and an average weight of 101 kg. The day before slaughter, longitudinal and transverse images were taken at the last rib. After slaughter, the lean meat content was estimated by a CGM (capteur gras-maigre) equipped with an 8-mm diameter Sydel probe. The carcass lean proportion was higher in homozygote TT than homozygote CC and heterozygote CT individuals (P < 0·05). Gilts had more lean meat than barrows (P < 0·05). The correlation between the lean meat proportion and ultrasound backfat thickness (UBFT) or ultrasound longissimus muscle depth (ULMD) respectively was moderate. The prediction of lean meat proportion using UBFT, ULMD and ULMA gave an R2 which varied from 0·35 to 0·79. Real-time ultrasound is a tool that could potentially be used to predict the composition of pig carcasses before slaughter particularly if measurements can be taken with a higher degree of accuracy than at present.
Effect of delayed castration on the growth rate, behaviour and serum insulin-like growth factor-1 concentration of beef cattle on tropical pasture
Authors: Gazzola C. , Jeffery M. R. , White D. H. , Hill R. A. , Reid D. J.
Published: August 2016

Male beef calves in northern Australia are generally castrated under 6 months of age as an aid to management of animal behaviour and for the purpose of producing sufficiently fat carcasses at slaughter. It is also common for beef producers to administer hormone growth promotants, such as oestradiol, to increase the growth rates of steers at pasture. This experiment tested the hypothesis that delaying castration by 9 months would produce an increase in growth rate for the period while the cattle are retained as bulls without compromising management of animal behaviour. Bulls of three genotypes were castrated at 7 months or 16 months of age and half were treated with oestradiol after castration. Body weight (BW) and serum insulin-like growth factor-1 concentrations (IGF-1) were measured and behaviour was observed before and after the 16 month castration. At both 7 and 16 months of age, surgical castration of bulls caused no animal welfare problems. BW gain was affected by genotype with Bos taurus types having a lower BW gain than Bos indicus and F1-cross cattle. IGF-1 was similarly affected by genotype. Oestradiol treatment increased growth of the steers (early castrates) during the 9 months between castration times compared with non-implanted steers and bulls. Oestradiol implanted steers had similar BW gain from the late castration to slaughter, regardless of age at castration, which was greater than non-implanted early castrates which, in turn, was greater than the late castrates. Similar differences were observed for IGF-1 concentrations. Behaviour was not affected by genotype, oestradiol treatment or age of castration but this may have been an artefact of the design where all treatment groups were grazed together. Although delayed castration resulted in no behavioural or management problems, it did not produce a commercially useful increase in growth rate.
The effect of maize starch or soya-bean oil as energy sources in lactation on sow and piglet performance in association with sow metabolic state around peak lactation
Authors: Jones G.M. , Edwards S.A. , Sinclair A.G. , Gebbie F.E. , Rooke J.A. , Jagger S. , Hoste S.
Published: August 2016

The effects of different energy sources in the lactation diet on sow and piglet performance were assessed in association with effects on the metabolic state of the sow around peak lactation. Either maize starch (S) or soya-bean oil (F) was added to a basal diet to provide 0·34 of total digestible energy (DE) intake, such that the experimental diets provided the same daily intakes of DE and crude protein. Twenty-four multiparous sows were allocated between two groups at farrowing, each given one of the two dietary treatments for a lactation period of 28 days. Sow weight and backfat (P2) as well as individual piglet weights were measured on a weekly basis. Litter sizes were standardized to 10 piglets. Milk samples were collected from sows on days 8, 12, 17, 21 and 25 of lactation to measure milk composition and prolactin concentrations. Blood samples were taken via an ear vein catheter from a subsample (7 S, 6 F) of sows on day 14 of lactation; two pre- and seven post-feeding samples were taken at 60-min intervals to measure plasma prolactin, insulin, glycerol, triglyceride, non-esterified fatty acid, urea, b-hydroxybutyrate and glucose concentrations. There was no effect of energy source on sow weight or P2 loss or on subsequent weaning-to-oestrus interval. Sows offered starch weaned more piglets than sows offered soya-bean oil (9·4 v. 8·4, P < 0·05). Litter weight gains were higher for S than F sows in week 3 of lactation (2·2 v. 1·7 kg/day, P < 0·05), irrespective of litter size. Significantly increased plasma urea and b-hydroxybutyrate concentrations and lower post-prandial increases in plasma glucose and insulin concentrations were observed in F sows around peak lactation. Neither milk nor plasma prolactin concentrations were significantly affected by dietary treatments. The metabolic indices indicated that the F diet was more limiting in dietary glucose availability, which was associated with impaired milk yield as indicated by poorer litter performance. In conclusion, this study suggests that starch is superior to fat as an energy source in sow lactation diets, particularly in the later stages of lactation.
Polyethylene glycol in concentrate or feedblocks to deactivate condensed tannins in Acacia cyanophylla Lindl. foliage 1. Effects on intake, digestion and growth by Barbarine lambs
Authors: Ben Salem H. , Atti N. , Priolo A. , Nefzaoui A.
Published: August 2016

Thirty young male sheep were given air-dried foliage of Acacia cyanophylla Lindl. ad libitum and 400 g oat hay. Animals were divided into five equal groups each of which was supplemented with either 300 g concentrate with (CPEG) or without (C) 20 g polyethylene glycol 4000 (PEG) or urea-containing feedblocks with (BUPEG) or without (BU) PEG. One other treatment was PEG-containing feedblock without urea (BPEG). PEG was used to preferentially bind A. cyanophylla condensed tannins (CT). Feedblocks (BU, BPEG and BUPEG respectively) were made from olive cake (395, 376 and 353), wheat bran (263, 250 and 235), wheatfeeds (132, 125 and 118), quicklime (88, 83 and 78), salt (44, 42 and 39), mineral and vitamin supplement (12, 10 and 10), urea (66, 0 and 59) and PEG (0, 114 and 107 g/kg). These diets were used in growth (60 days) and metabolism (7 days) studies. Urea-containing feedblocks, as compared with concentrate, were higher in crude protein (CP; 235 v. 116 g/kg DM) and lower in metabolizable energy (6 v. 10 MJ/kg DM). The type of supplement (i.e. concentrate v. feedblocks) had no effect (P > 0·05) on A. cyanophylla DM intake, CP and neutral-detergent fibre (NDF) digestibilities and nitrogen (N) retention. However, concentrate-containing diets exhibited higher DM and organic matter (OM) digestibilities (P < 0·05), urinary excretion of allantoin (P < 0·05), microbial N supply (P < 0·001) and average daily gain (P < 0·001). PEG supply increased DM intake of A. cyanophylla, CP digestibility, N retention, allantoin voided in urine, microbial N supply and lamb growth. PEG-containing feedblocks enriched (BUPEG) or not (BPEG) with urea had similar effect on A. cyanophylla intake, DM, OM and NDF digestibilities, allantoin in urine, microbial N supply and average daily gain. These findings suggested that urea inclusion in feedblocks are not necessary and thus the feeding cost may be reduced. The higher amount of microbial N and daily gain in lambs given concentrate as compared with those on feedblock-supplemented diets was ascribed to the level of energy which was low in the latter diets. Enrichment of feedblocks with energy-rich ingredients such as molasses or cactus fruits could be a solution. This work confirmed that tannins depressed the nutritive value of this shrub species and lamb growth. However, the reduction was not drastic in the absence of PEG in the diet. Feedblock diet (BU) matched maintenance requirements of lambs while lambs on concentrate-supplemented diet (C) grew at a rate of 78 g/day. The choice between these two supplements will depend upon farm conditions and objectives.
Polyethylene glycol in concentrate or feedblocks to deactivate condensed tannins in Acacia cyanophylla Lindl. foliage 2. Effects on meat quality of Barbarine lambs
Authors: Priolo A. , Ben Salem H. , Atti N. , Nefzaoui A.
Published: August 2016

Twenty-five male Barbarine lambs aged approximately 150 days were divided into five groups. All the animals received 400 g/day of oat hay and Acacia cyanophylla Lindl. foliage ad libitum. Two groups also received 300 g/ day of a mixture (70: 30) of processed barley and wheat bran, with or without 20 g polyethylene glycol 4000 (PEG), groups CPEG and C respectively. The three other groups had free access to feedblocks based on olive cake, and containing urea, urea and PEG, or PEG, groups BU, BUPEG and BPEG respectively. Lambs were slaughtered at age 230 days and meat quality was determined in the longissimus thoracis et lumborum muscle. Lean colour was significantly affected by dietary condensed tannins. Lightness (L*) was higher in those animals that did not receive PEG (P < 0·001) indicating that condensed tannins can cause lighter meat colour. This difference was not due to the ultimate pH, which was not affected by the inclusion of PEG in the diet. Meat from groups that received supplementation of concentrate had lower values of resistance to the Warner-Bratzler shear device compared with those that received feedblocks. This result was confirmed by a taste panel, that found samples from groups C and CPEG more tender than samples from groups BU, BUPEG and BPEG. Inclusion of PEG in the diet increased intensity of flavour (P < 0·05) but had no effect on overall acceptability. Meat from animals that had received the concentrate had higher overall acceptability (P < 0·05) than meat from animals that received the feedblocks. No differences were found in meat chemical composition.
Characterization of indigenous African cattle breeds in relation to carcass characteristics
Authors: Strydom P.E. , Naudé R.T. , Smith M.F. , Scholtz M.M. , van Wyk J.B.
Published: August 2016

Carcass traits of two indigenous African (Sanga) breeds (Afrikaner and Nguni), one indigenous African composite breed (Bonsmara), one foreign composite breed (Santa Gertrudis) and two continental European breeds (Brown Swiss and Pinzgauer) were compared. Treatment means were adjusted to the mean overall subcutaneous fat proportion (47 g/kg). Despite differences in maturity type, only the Afrikaner dressed out significantly (P < 0·05) lower than the foreign breeds. Both Sanga breeds and the Bonsmara had significantly higher muscle yields than the Santa Gertrudis and Pinzgauer, mainly due to the high intermuscular fat of the latter two breeds. When muscle yield was expressed per unit of bone, the Afrikaner and Bonsmara compared favourably with the larger breeds, due to their low bone and intermuscular fat yield, while the Nguni had a relatively high bone yield. The Santa Gertrudis had the lowest muscle yield due to its high bone and intermuscular fat yields, especially when compared with the smaller Bonsmara composite. Both Sanga breeds had significantly higher (P < 0·05) proportions of total weight, meat and bone (Afrikaner P > 0·05) in the high-priced cuts compared with the other breeds at the same subcutaneous fat level. Despite the statistical significance, differences were small in magnitude and probably of little commercial value. At the same time mean subcutaneous fat proportion, tissue yield and distribution patterns expected of late maturing breeds were observed for smaller indigenous breeds, suggesting that it was specific breed effects rather than maturity type effects, which were evident.
Influence of the nature of dietary fibre on digestive utilization, some metabolite and hormone profiles and the behaviour of pregnant sows
Authors: Ramonet Y. , Robert S. , Aumaître A. , Dourmad J.Y. , Meunier-Salaün M.C.
Published: August 2016

Three diets were formulated according to the nature of the fibrous components: a concentrate low fibre diet enriched in starch (diet S, neutral-detergent fibre (NDF) proportionately 0·078 of dry matter (DM)) and two high-fibre diets enriched in either sugar-beet pulp (diet BP, NDF = 0·219 of DM) or wheat bran (diet WB, NDF = 0·187 of DM). In a first experiment, the digestibility of nutrients in these diets were determined using dry sows. In a second experiment, 24 multiparous Large White sows were offered the experimental diets in a 3 x 3 Latin-square design during three 21-day periods over pregnancy in order to evaluate physiological and behavioural effects over the nycthemeral period. On the basis of the first experiment, the daily food supply was adjusted to 2·44, 2·74 and 2-90 kg/day for diets S, BP and WB, respectively, to provide the same amount of metabolizable energy to each treatment. In the hour prior to the meal, the diet effect was nil on plasma levels of glucose, insulin, glucagon and non-esterified fatty acid and limited on cortisol plasma level. After the food delivery, the peak responses of glucose and insulin to the meal were delayed in sows given the BP diet, while their level showed a higher increase for S than for WB and BP diets. Sows offered diet BP spent less time standing than sows offered diet S. The occurrence of non-feeding oral activities over the 45 min following food distribution was significantly reduced with fibrous diets. But no difference appeared during the 45-min period following the end of each meal. It was concluded that the incorporation of beet pulp in the diet was more effective than wheat bran in extending the feeding activity and the absorption of nutrients. The diet effect was limited to the 2 h after the food delivery for these sows given a restricted amount of food.
Effects of dietary supplementation and work stress on ovarian activity in non-lactating Mashona cows in a small-holder farming area of Zimbabwe
Authors: Chimonyo M. , Kusina N. , Hamudikuwanda H. , Nyoni O. , Ncube I.
Published: August 2016

The effects of work stress and dietary supplementation on ovarian activity were determined in 16 multiparous Mashona cows in Sanyati Communal Area, which lies in a semi-arid environment of Zimbabwe. The cows were assigned to one of four treatments: supplemented working (SW), supplemented non-working (SNW), non-supplemented working (NSW) and non-supplemented non-working (NSNW) cows in a 2 × 2 factorial treatment arrangement with two dietary and two work levels. Cows in the SW and NSW groups pulled a cart with a 200-1 water drum for 18 km (9 km with drum empty, 9 km with drum full) every day for 5 days/week for a total of 12 weeks.

Rectal temperatures were recorded at specific points along the route to and from the river where the water was obtained. Blood samples were collected by jugular venipuncture once a week, before working, for the determination of plasma glucose and non-esterified fatty acids (NEFA). In addition, blood samples were collected once every 3 days for the determination of progesterone concentration. There were no differences (P> 0⋅05) in the rectal temperatures between SW and NSW cows. Cows in the NSW group had the highest decrease in glucose levels and also showed marked increases in NEFA concentrations. The incidence of ovarian activity was similar between SNW and SW cows (P> 0⋅05). The incidence of ovarian activity was least in NSW cows. We conclude that nutritional stress was more important in suppressing ovarian activity than work stress and that dietary supplementation can reduce the negative effects of draught on ovarian activity.
Genetic parameters for growth and carcass traits of Japanese Black (Wagyu) cattle
Authors: Oikawa T. , Sanehira T. , Sato K. , Mizoguchi Y. , Yamamoto H. , Baba M.
Published: August 2016

Restricted maximum likelihood analyses fitting an animal model were conducted to estimate genetic parameters with a pooled-data set of performance tests (growth traits and food intake) on 661 bulls and progeny tests (growth traits and carcass traits) on 535 steers. Traits studied included concentrate intake (CONC), roughage intake (ROU), TDN conversion (TCNV), TDN intake (TINT) of bulls; rib eye area (REA), marbling score (MARB), dressing proportion (DRES) and subcutaneous fat depth (SCF) of steers. Body weight at start (BWS), body weight at finish (BWF) and average daily gain (ADG) of all animals were measured. Estimated heritabilities were 0·18 (CONC), 0·71 (ROU), 0·11 (TCNV) and 0·36 (TINT); 0·02 (REA), 0·49 (MARB), 0·15 (DRES), 0·15 (SCF), and from 0·20 to 0·38 for growth traits. Genetic correlations of ROU were different from those of CONC, probably due to inconsistent restrictions on concentrate intake; those of TINT with the weights, ADG and SCF were high. MARB showed positive genetic correlations with growth traits and low correlations with TINT and SCF. High potentiality for improvement of marbling score was suggested.
Effect of proteinate or sulphate mineral sources on trace elements in blood and liver of piglets
Authors: Schiavon S. , Bailoni L. , Ramanzin M. , Vincenzi R. , Simonetto A. , Bittante G.
Published: August 2016

Four hundred piglets were housed in 20 pens and offered for 42 days a pre-starter and then a starter compound supplemented with trace elements given as sulphates (SULF) or proteinates (PROT) at a common level (100) or at a reduced level (20) of inclusion. The common level supplied 278, 148, 315 and 98 mg/kg and the reduced level supplied 128, 38, 135 and 50 mg/kg of iron (Fe), copper (Cu), zinc (Zn) and manganese (Mn), respectively, taking into account the natural food contents. Proteinates used in the trial were analysed and described in terms of content and quality of different potential ligands. Piglet growth was not affected by any treatment. At the end of the trial blood samples were collected from eight pigs for each treatment. These animals were slaughtered and their livers were removed, weighed and analysed. Compared with SULF, PROT increased significantly plasma levels of Fe (25·1 v. 15·7 μmol/l), haemoglobin (10·9 v. 10·4 g/dl) and the number of red blood cells (6·4 v. 6·1 millions per μl) but the liver recovery of Fe was not affected by any treatment. In piglets receiving PROT the liver content of Cu and Zn increased significantly compared with those receiving SULF. On reducing the dosage, Cu in the liver significantly decreased with SULF but not with PROT and the amount of Zn decreased more with SULF than with PROT. The results may reflect a better availability of Cu and Zn when proteinates rather than sulphates were used as mineral supplements.
The development of suckling frequency in pigs from birth to weaning of their piglets: a sociobiological approach
Authors: Puppe B. , Tuchscherer A.
Published: August 2016

The suckling frequency in 34 first-lactation sows and their litters in conventional farrowing pens was observed during a 35-day lactation period from birth to weaning. In order to quantify the ontogenetic development of this behaviour a non-linear regression function was used as a model. The maximum (MAX) of the curve was determined at day 8×5 (31×4 sucklings per 24-h period) and was considered as the biological beginning of the weaning process. The occurrence of MAX was shifted towards an earlier time by about 6 days earlier from small (4 to 7 piglets per litter) to large litters (11 to 14 piglets per litter). However, no significant influence of the litter size on the development of the daily suckling frequency and the average individual piglet weight was found. Nevertheless, there was a tendency for an inverse relationship between the litter size and the piglet weight during lactation and, further, for an increased daily suckling frequency during early lactation and a lower frequency during late lactation in larger litters. As a compensation for the decreasing suckling frequency piglets markedly increased their creep food consumption in the last week of the suckling period (day 28 to 35). The results indicate that the suckling behaviour in domestic pigs reflects sow-piglet relationships which are consistent with a theoretically predicted model of weaning conflict. Hence, it is suggested that modelling the suckling behaviour using well defined and comparable measures may be a suitable approach for the evaluation of the weaning process both in terms of sociobiology (e.g. weaning conflict, parent-offspring conflict) and of farm animal science (e.g. performance, housing conditions).
Monthly variations in some reproductive parameters of Barki and Awassi rams throughout 1 year under subtropical conditions 2. Biochemical and enzymatic properties of seminal plasma
Authors: Taha T. A. , Abdel-Gawad E. I. , Ayoub M. A.
Published: August 2016

Fifteen sexually mature rams, five each of Barki, Awassi (I, imported from Syria) and Awassi (LB, locally born in Egypt) were used to study the biochemical and enzymatic properties of seminal plasma for 12 months. The biochemical analyses of ram seminal plasma indicated that the highest values of total protein, albumin (A), globulin (G), fructose, total lipids and cholesterol were recorded in late summer and early autumn, while A/G and AST/ALT ratios exhibited the lowest values. Lowest values of the same parameters were recorded in winter and late spring, while ratios of A/G and aspartate amino transferase (AST)/alanine amino transferase (ALT) showed the highest values in spring. AST enzyme activity showed highest activity in winter and summer and lowest activity in autumn, while ALT exhibited the highest activity in winter and the lowest activity in spring. The relationships between these parameters and semen quality are discussed.
Effect of amount ofPanicum virgatumhay offered on intake, apparent digestibility and short-term intake rate of rams
Authors: Ferri C. M. , Stritzler N. P. , Petruzzi H. J. , Cerqueira E. D.
Published: August 2016

Switchgrass (Panicum virgatumcv.Alamo) standing hay was cut and offered to 16 rams. The rams were randomly allocated to one of the following levels of feeding: 0·5; 1·0; 1·5 and 2·0✕maintenance. The forage was offered twice a day to the animals; no supplements were given. The animals were individually penned and fitted with faeces collection bags. After 8 days for adaptation, in vivo dry matter apparent digestibility (DMD) and proportion of blades and stem + sheath of the consumed forage were measured for 8 days. DMD varied from 0·310 (0·5) to 0·391 (2·0) and the proportion of the blade fraction in the diet from 0·44 (0·5) to 0·78 (2·0). The short-term intake rate (STIR) of rams was measured for 5 days. The animals were divided randomly into four blocks, with one ram of each treatment in each block. After 4 h without food and 15 min intervals between blocks, the amount of forage consumed during 4 min of active eating was measured. The amounts consumed were (in g DM per min per 50 kg live weight): 0·5: 8·2; 1·0: 7·8; 1·5: 5·3 and 2·0: 5·3 (0·5 = 1·0 > 1·5 = 2·0;P< 0·01). The results show that offer rate of P. virgatum affects the blade: stem + sheath ratio of intake and, therefore, the nutritive value of the diet. Level of feeding before measuring STIR influences the amount of forage consumed during the test.
The effect of crop maturity on the nutritional value of maize silage for lactating dairy cows. 3. Food intake and milk production
Authors: Phipps R. H. , Sutton J. D. , Beever D. E. , Jones A. K.
Published: August 2016

Fifty-five multiparous Holstein-Friesian cows were used in a 20-week continuous design study to determine the effect of maize silage maturity on food intake and milk production. Forage maize (cv. Hudson) was harvested and ensiled at target dry matter (DM) contents of 230 (T23), 280 (T28), 330 (T33) and 380 (T38) g per kg fresh weight (FW). The mean values for volatile-corrected DM (VCDM), starch, neutral-detergent fibre (NDF), crude protein and predicted metabolizable energy (ME) content of the four maize silages were 226, 290, 302 and 390 g/kg FW, 114, 274, 309 and 354 g/kg VCDM, 574, 447, 431 and 448 g/kg VCDM, 96, 80, 74 and 75 g/kg VCDM and 10·3, 11·5, 11·6 and 11·2 MJ/kg DM, respectively. Grass silage containing 296 g VCDM per kg FW was produced from the primary growth of a perennial ryegrass sward. At week 3 of lactation cows were allocated to one of five forage treatments offered ad libitum. The forage treatments were either grass silage alone (TGS) or a 3 : 1 DM ratio of maize and grass silage designated as T23, T28, T33 and T38. All cows also received 8·7 kg DM per day of a dairy concentrate. Forage VCDM intake for TGS was lower (P < 0·001) than for T23 to T38. Increasing maize silage DM content from 226 (T23) to 290 (T28) g/kg increased (P < 0·05) forage VCDM intake from 10·9 to 13·3 kg/day but a further increase to 390 (T38) g/kg tended to reduce VCDM intake. When compared with TGS, the inclusion of maize silage increased milk yield from 28·0 kg/day to 29·4, 32·7, 33·0 and 30·8 kg/day for T23 to T38, respectively, the increases being significant for T28 to T38. However, milk yield was reduced (P < 0·05) when the DM content of the maize silage increased from 302 to 390 g/kg. Increasing maize silage DM content from T23 to T33 reduced (P < 0·05) milk fat content from 45·8 to 41·8 g/kg, which was also lower (P < 0·05) than for TGS. The inclusion of maize silage increased fat yield with a significant difference (P < 0·05) between TGS and T28. The inclusion of maize silage increased milk protein content (P < 0·05) and protein yield (P < 0·001) when compared with TGS. While increasing maize silage maturity did not affect (P > 0·05) milk protein content, protein yield was higher (P < 0·05) for the two intermediate DM contents. There were no treatment effects on body condition score. It is concluded that the changes in composition of maize silage with increasing maturity, which are associated with increased starch and reduced NDF content, resulted in large increases in food intake and yield of milk and protein as crops matured from T23 to T33. However, when crop maturity increased further to T38 there was a tendency for DM intake and yield of milk and protein to decline.
The effect of change of the diet and feeding regimen at weaning on duodenal myoelectrical activity in piglets
Authors: Lesniewsk V. , Lærke H. N. , Hedemann M. S. , Højsgaard S. , Pierzynowski S. G. , Jensen B. B.
Published: August 2016

This study investigated the effect of the change of diet and feeding regimen at weaning on myoelectrical activity of the intestine of piglets. For this purpose the electromyographic recordings of duodenal myoelectrical activity were carried out in relation to the different weaning status of piglets. Six piglets, in two experimental trials were surgically modified with two serosal, bipolar electrodes on the duodenum. The myoelectrical activity was recorded in the same piglets before weaning when they were sucking their sow and after weaning when the diet was changed to solid dry food (standard commercial concentrate for weaned pigs). In sucking piglets the intestinal myoelectrical activity pattern exhibited triple-phased migrating myoelectric complex (MMC), undisturbed by sow nursing. After weaning, feeding with solid food induced a long-term post-prandial pattern with higher frequency of electrical response activity (ERA) when compared with phase II of the MMC. The duration of the MMC cycles increased with time over the experiment by proportionately 0•11 and 0•14 in the periods before and after weaning. However, weaning significantly shortened MMC cycle duration by proportionately 0•21. The duration of phase II was significantly prolonged with time over the experiment by 0•07 to 0•10 and it was not affected by weaning. Phase III of MMC were of constant duration over the whole experimental period.

In summary, changes in the diet and feeding regimen have an influence on the characteristics of intestinal myoelectrical activity in piglets around weaning.
Effects of dietary linseed on nutritional value and other quality aspects of pig muscle and adipose tissue
Authors: Riley P. A. , Enser M. , Nute G. R. , Wood J. D.
Published: August 2016

This study reports improvements in the nutritional value of pork by including linseed in the diets of boar and gilt pigs. Two feeding strategies, either short-term or long-term, were employed: (i) 0 g or 114 g linseed per kg of food provided to 16 pigs of 87 kg live weight for 20 or 27 days; (ii) 0 g, 10 g, 20 g or 30 g linseed per kg of food provided to 64 pigs of 46 kg live weight for 54, 62, 68 or 75 days. All diets were supplemented with DL-α-tocopheryl acetate (0•2 g/kg). The 18 : 3n-3 contents (18 : 2n-6 :18 : 3n-3 ratios in parentheses) of the short-term 0 g and 114 g/kg, and long-term 0g, 10 g, 20 g and 30 g/kg linseed diets, were 2•1 g (7•75), 28•1 g (0•70), 1•0 g (8•86), 3•4 g (2•73), 6•0 g (1•66) and 8•1 g/kg food (1•25) respectively. The long-term 30 g/kg diet reduced the n-6 : n-3 ratio of muscle and adipose tissue as successfully as the short-term 114 g/kg diet to accord with guidelines for the overall human diet (5 :1 or less) but required only 0•73 as much linseed and increased the proportion of C20-22 n-3 fatty acids more effectively; compared with their respective control diets, the 114 g/kg and 30 g/kg diets more than halved the n-6 : n-3 ratios in muscle to 3•8 and 3•9, approximately trebled the concentrations of 18 : 3n-3 in muscle to 0•43 mg and 0•28 mg/g tissue, and doubled the concentrations of 20: 5n-3 in muscle to 0•08 mg and 0•10 mg/g tissue. Similar changes occurred in adipose tissue. With both strategies, the majority of the changes had occurred by the time the first groups were slaughtered. There was a strong relationship between the 18 : 2n-6 :18 : 3n-3 ratio of the food and tissues and the accumulation of all C20-22 n-3 fatty acids, except 22 : 6n-3, which was unaffected by dietary linseed. The improvements in nutritional value were obtained without changes in organoleptic characteristics, as measured by a trained taste panel, or significant loss of shelf-life, as measured by TBARS analysis and colour stability.
The influence of sow behaviour on piglet mortality due to crushing in an open farrowing system
Authors: Marchant J. N. , Broom D. M. , Corning S.
Published: August 2016

The objectives of this study were to establish what changes in posture by sows carried a high risk of piglet crushing in a group farrowing system during early lactation and also to determine what factors influenced the risk of crushing during lying down. A total of 24 Large White ✕ Landrace sows were studied during the first 7 days of lactation in a group farrowing system. Cross-fostering was not carried out so as not to influence behaviour. Dead piglets were removed and cause of death ascertained from external observation and post-mortem examination. Sow and piglet behaviour was video-recorded continuously. A total of 268 piglets were born alive, with 67 liveborn piglets subsequently dying during the 7-day experimental period, 50 as a result of crushing. A total of 7425 posture changes were analysed and 11 types of posture change were identified, the most dangerous being lying down from standing and those involving swapping sides, or rolling over, whilst lying.

Dangerous events during lying down were more likely to occur (1) in the first 24 h after farrowing, (2) when the sow lay down in the middle of the pen, (3) when the sow lay down without carrying out much piglet-directed pre-lying behaviour and (4) when the piglets were spread out but near to the sow. The amount of pre-lying behaviour decreased over time and crushing mortality also decreased. The results confirm that the piglets are most vulnerable to crushing during the first 24 h of life, when they are spending much of their time near the udder and have relatively poor mobility. Co-ordination of behaviour between the sow and her litter is important to reduce the risk of crushing. It is also important that the design of open farrowing systems incorporates knowledge about how crushing deaths occur in order to improve piglet welfare.
Genetic evaluation of dairy bulls for energy balance traits using random regression
Authors: Coffey M. P. , Emmans G. C. , Brotherstone S.
Published: August 2016

Current selection objectives for dairy cattle breeding may be favouring cows that are genetically predisposed to mobilize body tissue. This may have consequences for fertility since cows may resume reproductive activity only once the nadir of negative energy balance (NEB) has passed. In this study, we repeatedly measured food intake, live weight, milk yield and condition score of Holstein cattle in their first lactation. They were given either a high concentrate or low concentrate diet and were either selected or control animals for genetic merit for kg milk fat plus milk protein. Orthogonal polynomials were used to model each trait over time and random regression techniques allowed curves to vary between animals at both the genetic and the permanent environmental levels. Breeding values for bulls were calculated for each trait for each day of lactation. Estimates of genetic merit for energy balance were calculated from combined breeding values for either (1) food intake and milk yield output, or (2) live weight and condition-score changes.

When estimated from daily fluxes of energy calculated from food intake and milk output, the average genetic merit of bulls for energy balance was approximately -15 MJ/day in early lactation. It became positive at about day 40 and rose to +18 MJ/day at approximately day 150. When estimated from body energy state changes the NEB in early lactation was also -15 MJ/day. It became positive at about day 80 and then rose to a peak of +10 MJ/day. The difference between the two methods may arise either because of the contribution of food wastage to intake measures or through inadequate predictions of body lipid from equations using live weight and condition score or a combination of both. Body energy mobilized in early lactation was not fully recovered until day 200 of lactation. The results suggest that energy balance may be estimated from changes in body energy state that can be calculated from body weight and condition score. Since body weight can be predicted from linear type measures, it may be possible to calculate breeding values for energy balance from national evaluations for production and type. Energy balance may be more suitable as a breeding objective than persistency.
Effect of weaning age and slaughter weight on carcass and meat quality of Talaverana breed lambs raised at pasture
Authors: Cañeque V. , Velasco S. , Díaz M. , Pérez C. , Huidobro F. , Lauzurica S. , Manzanares C. , González J.
Published: August 2016

Three weaning treatments (weaning at 45 days of age, at 65 days of age, unweaned) and two slaughter weights (24 and 28 kg) were compared in lambs raised at pasture, and their effect on carcass and meat traits were studied. Unweaned lambs displayed a greater growth rate, lower concentrate consumption, greater dorsal fat thickness, more kidney knob and channel fat and greater total fat levels, measured through dissection of the hind limb. Total collagen concentration was lower in unweaned lambs and the intramuscular fat of these same animals exhibited a greater proportion of saturated fatty acids and a lower n-6/n-3 fatty acid ratio. Slaughter weight influenced scored carcass fatness, which was greater in heavier lambs, meat colour, which displayed greater lightness in lower-weight lambs, and water-holding capacity, which was lower in lambs with the lower slaughter weight. The heavier lambs displayed lower soluble collagen values, and the intramuscular fat of thelongissimus dorsimuscle of these same lambs contained higher levels of monounsaturated and lower levels of polyunsaturated fatty acids.
Genetic parameters for clinical mastitis in Holstein-Friesians in the United Kingdom: a Bayesian analysis
Authors: Kadarmideen H. N. , Rekaya R. , Gianola D.
Published: August 2016

A Bayesian threshold-liability model with Markov chain Monte Carlo techniques was used to infer genetic parameters for clinical mastitis records collected on Holstein-Friesian cows by one of the United Kingdom’s national recording schemes. Four data sets were created to investigate the effect of data sampling methods on genetic parameter estimates for first and multi-lactation cows, separately. The data sets were: (1) cows with complete first lactations only (8671 cows); (2) all cows, with first lactations whether complete or incomplete (10 967 cows); (3) cows with complete multi-lactations (32 948 records); and (4) all cows with multiple lactations whether complete or incomplete (44 268 records). A Gaussian mixed linear model with sire effects was adopted for liability. Explanatory variables included in the model varied for each data set. Analyses were conducted using Gibbs sampling and estimates were on the liability scale. Posterior means of heritability for clinical mastitis were higher for first lactations (0·11 and 0·10 for data sets 1 and 2, respectively) than for multiple lactations (0·09 and 0·07, for data sets 3 and 4, respectively). For multiple lactations, estimates of permanent environmental variance were higher for complete than incomplete lactations. Repeatability was 0·21 and 0·17 for data sets 3 and 4, respectively. This suggests the existence of effects, other than additive genetic effects, on susceptibility to mastitis that are common to all lactations. In first or multi-lactation data sets, heritability was proportionately 0·10 to 0·19 lower for data sets with all records (in which case the models had days in milk as a covariate) than for data with only complete lactation records (models without days in milk as a covariate). This suggests an effect of data sampling on genetic parameter estimates. The regression of liability on days in milk differed from zero, indicating that the probability of mastitis is higher for longer lactations, as expected. Results also indicated that a regression on days in milk should be included in a model for genetic evaluation of sires for mastitis resistance based on records in progress.
Effect of double-muscling in Belgian Blue young bulls on the intramuscular fatty acid composition with emphasis on conjugated linoleic acid and polyunsaturated fatty acids
Authors: Raes K. , Smet S. de , Demeyer D.
Published: August 2016

The effect of double-muscling (DM) genotype (double-muscling, mh/mh; heterozygous, mh/+; normal, +/+) of Belgian Blue (BB) young bulls on the intramuscular fatty acid composition, in particular conjugated linoleic acid (CLA) and polyunsaturated fatty acids (PUFA) was examined in five different muscles. The relative fatty acid composition showed only minor differences between muscles within genotypes. However, the DM genotype had a large effect on both the intramuscular total fatty acid content and on the relative fatty acid composition. Across muscles, the mh/mh animals had a lower total fatty acid content compared with the +/+animals (907 v: 2656 mg/100 g muscle;P< 0·01) and a higher PUFA proportion in total fatty acids (27·5 v 11·3 g/100 g total fatty acids;P< 0001), resulting in a higher PUFA/saturated fatty acid ratio (0·55 v 0·18;P< 0·01) and a lower n-6/n-3 ratio (5·34 v. 6·17;P< 0·01). The heterozygous genotype was intermediate between the two homozygous genotypes. The relative CLA content was similar in the mh/mh and +/+ genotypes and approximated 0·4 to 0·5 g/100 g total fatty acids. From the data it is further suggested that differences in the metabolism of the n-3 and n-6 fatty acids could exist between DM genotypes.