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Subcutaneous fat from Norwegian Landrace (n = 3230) and Duroc (n = 1769) pigs was sampled to investigate the sources of variation and genetic parameters of various fatty acids, fat moisture percentage and fat colour, with the lean meat percentage (LMP) also included as a trait representing the leanness of the pig. The pigs were from half-sib groups of station-tested boars included in the Norwegian pig breeding scheme. They were fed ad libitum to obtain an average of 113 kg live weight. Near-infrared spectroscopy (NIRS) was applied for prediction of the fatty acids and fat moisture percentage, and Minolta was used for the fat colour measurements. Heritabilities and genetic correlations were estimated with a multi-trait animal model using average information-restricted maximum likelihood (AI-REML) methodology. Fat from Landrace pigs had considerably more monounsaturated fatty acids, polyunsaturated fatty acids (PUFAs) and fat moisture, as well as less saturated fatty acids (SFAs) than fat from Duroc pigs. The heritability estimates (s.e. 0.03 to 0.08) for the various fatty acids were as follows: Palmitic, C16:0 (0.39 and 0.51 for Landrace and Duroc pigs, respectively); Palmitoleic, C16:1n-7 (0.41 and 0.50); Steric, C18:0 (0.46 and 0.54); Oleic, C18:1n-9 (0.67 and 0.57); Linoleic, C18:2n-6 (0.44 and 0.46); α-linolenic, C18:3n-3 (0.37 and 0.25) and n-6/n-3 ratio (0.06 and 0.01). The other fat quality traits revealed the following heritabilities: fat moisture (0.28 and 0.33), colour values in subcutaneous fat: L* (whiteness; 0.22 and 0.21), a* (redness; 0.13 and 0.24) and b* (yellowness; 0.07 and 0.17) and LMP (0.46 and 0.47). LMP showed high positive genetic correlations to PUFA (C18:2n-6 and C18:3n-3), which implies that selecting leaner pigs changes the fatty acid composition and deteriorates the quality of fat. Higher concentrations of PUFA are not beneficial as the ratio of n-6 and n-3 fatty acids becomes unfavourably high. Owing to the high genetic correlation between C18:2n-6 and C18:3n-3 and a low heritability for this ratio, the latter is difficult to change through selection. However, a small reduction in the ratio should be expected if selection aims at reducing the level of C18:2n-6. Selection for more C18:1n-9 is possible in view of the genetic parameters, which are favourable for eating quality, technological quality and human nutrition. The NIRS technology and the high heritabilities found in this study make it possible to implement fat quality traits to achieve the breeding goal in the selection of a lean pig with better fat quality.
Two experiments were conducted to investigate the requirement for dietary crude protein (CP) in growing blue-breasted quail (BBQ). In Experiment 1, 300 1-day-old quails were randomly assigned to 10 groups according to a 2 × 5 factorial arrangement of treatments with two metabolisable energy (ME) levels (12.13 and 13.39 MJ/kg) and five CP concentrations (160, 190, 220, 250 and 280 g/kg) for 8 weeks. In Experiment 2, 300 1-day-old quails were subjected to a different factorial arrangement of treatments with two ME levels (11.51 and 12.13 MJ/kg) and five CP concentrations (210, 220, 230, 240 and 250 g/kg) for 28 days. Experiment 1 revealed that an interaction existed in weight gain between ME and CP levels in weeks 1 to 4. In both ME groups, quails receiving CP of 160 g/kg showed the least weight gains (P < 0.05). No differences (P > 0.05) existed in weight gain between the ME groups in which quails ingested CP of 250 and 280 g/kg, whereas quails consuming CP of 220 g/kg with an ME of 13.39 MJ/kg had smaller weight gain than did those ingesting higher CP concentrations (P < 0.05). Of main effects for weeks 1–4, quails treated with an ME of 12.13 MJ/kg consumed more feed than did those receiving another ME level, whereas quails in both ME treatments showed similar feed efficiencies. For weeks 5 to 8, no difference (P > 0.05) in weight gain, feed intake and feed efficiency was seen regardless of ME levels, and no interaction existed between ME and CP levels. In Experiment 2, the best weight gain and feed efficiency were achieved when the dietary CP concentration was more than 210 g/kg, and quails treated with 11.51 MJ/kg showed better weight gain and feed efficiency (P < 0.05) than did those that received 12.13 MJ/kg. Furthermore, the weight gains and protein intakes on the basis of per MJ from the two experiments were pooled together to estimate the protein intake necessary for the best growth performance by two mathematic models; they were then converted to dietary CP concentrations of 204 (minimum) and 233 g/kg (maximum) when ME was 11.51 MJ/kg. In conclusion, BBQ will achieve good growth performance with dietary CP of more than 204 g/kg on the basis of an ME of 11.51 MJ/kg in weeks 1 to 4.
The aim of this study was to investigate protein requirements for the maintenance and growth of blue-breasted quail (Excalfactoria chinensis) from 7 to 21 days of age. A total of 180 quails, 7 days old, were randomly assigned to 36 cages and for 2 weeks were fed diets with a metabolisable energy concentration of 12.13 MJ/kg and a dietary CP concentration of 125, 150, 175, 200, 225 or 250 g/kg. The average BW per cage and the feed intake per cage were recorded daily. The results showed that quails fed 125 g/kg CP could not maintain their BW and had negative feed efficiency. There were linear and quadratic relationships between CP level and response criteria, including BW, weight gain, feed intake, feed efficiency, final body nitrogen mass and body nitrogen accretion (P < 0.05). The dietary CP requirements, as calculated using a one-slope quadratic broken-line model, were 211 and 202 g/kg according to weight gain and feed efficiency, respectively. The regression equations, on the basis of metabolic BW, of daily weight gain on daily protein intake according to the model were Y = 0.137−2.128(0.113−X) if X < 0.113 and Y = 0.137 if X ⩾ 0.113 (R2 = 0.96, P < 0.001), which meant that the protein requirement for maintenance was 0.049 times the metabolic BW and that to gain 1 g weight quails needed to ingest an extra 0.47 g protein after the maintenance requirement was satisfied. The regression equations, on the basis of metabolic BW, of daily body nitrogen accretion on daily protein intake according to the model were Y = 5.667−76.700(0.119−X) if X < 0.119 and Y = 5.667 if X ⩾ 0.119 (R2 = 0.95, P < 0.001), which meant that quails had to receive an amount of protein equal to their metabolic BW multiplied by 0.045 to satisfy the requirement for maintenance and then ingest an extra 13 g protein to accrete 1 g body nitrogen. In conclusion, growth or protein accretion rates should be regulated according to dietary CP for specific experimental purposes via apportioning protein requirements for maintenance v. growth.
Tannins are phenolic compounds that interfere with biohydrogenation (BH) of polyunsaturated fatty acids (FAs). The aim of the present in vitro study was to investigate the effects of two different sources of tannins on FA profiles of rumen bacteria, with particular reference to rumenic and vaccenic acid. A control diet (C; composed of 300 g/kg of wheat straw, 132 g/kg of soyabean meal, 96 g/kg of barley meal, 152 g/kg of maize meal, 300 g/kg of maize gluten and 20 g/kg of mineral vitamin premix, all expressed on dry matter (DM)) and four diets, obtained by adding to C two different types of tannins from chestnut (TC) and from quebracho (TQ) at two concentration levels (49 and 82 g/kg DM), were compared. The content of the main unsaturated FAs (C18:1 cis9, C18:1 trans11, C18:2 cis9, cis12 and C18:3 cis9, cis12, cis15) from solid-associated bacteria (SAB) and liquid-associated bacteria (LAB) was affected by the presence of tannins in the diets. In particular, C18:1 trans11 content was significantly increased, especially with TC1, whereas the decreasing of C18:1 cis9 was unaffected, regardless of the presence or the kind of tannins added to feeds. SAB contained higher amounts of intermediates of polyunsaturated FA BH (as C18:1 trans11 and C18:2 cis9, trans11) than LAB that were characterized by a higher amount of C18:0. In the concentration range adopted in this study, the effect of TC and TQ on changes of bacterial FA profile was comparable. Tannins seem to be a good means to modulate the FA profile of rumen bacteria, favouring the accumulation of C18:1 trans11 during in vitro rumen fermentation.
The study aimed at comparing three strategies of supplementing selenium (Se) during the finishing period of Charolais young bulls: (1) administration of sodium selenite throughout the finishing (NaSe); (2) administration of an Se-enriched yeast strain (Saccharomyces cerevisiae NCYC R397) throughout the finishing (Se-Y); (3) administration of sodium selenite for 140 days replaced by Se-enriched yeast during the last 70 days of finishing (Switch). Eighty-four young bulls (mean initial BW = 434.2 ± 31.9 kg; mean age = 382 ± 52 days) were stratified by live weight and equally assigned to one of three Se treatments. Experimental groups were fed the same diets and the inclusion rate of the different treatments was targeted to achieve 0.3 mg of Se/kg of dry matter (DM) in the complete feed. The average daily gain of bulls was 1.36 kg/d and no differences due to Se treatment were recorded. Dry matter intake and feed conversion ratio were not affected by Se treatment resulting in, on average, 10.3 kg/d and 7.65, respectively. Repeated blood samples were taken at days 0, 120, 180 and 210 of finishing to assess the Se status of the animals. As compared to NaSe, both organic Se treatments (Se-Y and Switch) increased plasma Se in the last two sampling sessions according to a significant treatment × time interaction (P < 0.001). A similar trend was observed for serum total antioxidant status of the young bulls, whereas there was only a significant time effect (P < 0.001) on glutathione peroxidase activity that was raised by all Se treatments. The finishing period lasted 210 days and at the abattoir there were no differences across Se treatments in carcass weight and dressing percentage. A higher Se content in the Longissimus thoracis (LT) muscle was instead observed in Se-Y samples as compared with NaSe (0.85 v. 0.47 mg/kg DM; P < 0.05). Meat quality evaluation was carried out on LT samples after 6 and 11 days of ageing under a vacuum package. Regardless of ageing time, meat from young bulls supplemented with Se yeast had higher colour lightness (L*) values than those receiving NaSe (38.1 v. 36.6; P < 0.01) and showed a significant decrease in shear force (3.69 v. 4.22 kg/cm2; P < 0.01). The outcomes of the study suggest that the provision of Se yeast throughout the finishing period is a strategy to increase the benefits of the replacement of sodium selenite with organic selenium in beef cattle.
Twelve male 8-month-old lambs were used in a 6-month feeding experiment to determine the effects of dietary Mo, Mo + S and Zn supplements on the body retention and tissue accumulation of dietary Cu, Zn and Fe. The lambs were divided into four groups of three lambs each and each group was fed ad libitum one of four diets. A control diet was based on palm kernel cake (PKC) and grass hay. Three additional diets were the control supplemented with either Mo or Mo + S or Zn. At 3 months of the experiment, feces and urine were collected and sampled for 6 days. At the end of the experiment (6 months), blood was sampled and then the sheep were slaughtered. The liver and kidney were removed and sampled for chemical analysis. In comparison with the control, each dietary supplement decreased (P < 0.05) the Cu concentration in the liver, but only the Mo + S supplement decreased it to a safe range of below 350 μg/g dry matter. This was accompanied by the body retention of dietary Cu of 24.6%, 6.7%, 2.5% and 6.5% for the control, Mo, Mo + S and Zn treatments, respectively. The blood plasma concentration of Cu was decreased (P < 0.05) by the Zn supplement, but was not affected by other supplements (P > 0.05). It was concluded that from the supplements tested, only Mo + S appeared to be effective in reducing the retention and liver accumulation of the dietary Cu to prevent chronic Cu toxicity in sheep fed PKC-based diets.
Colostrum provides newborn piglets with energy, immunoglobulins and growth, thereby playing an essential role in piglet survival. However, colostrum yield and composition are highly variable among sows. Some of the factors involved in this variability have been identified. The aim of the study was to confirm previous findings on a large number of animals and to investigate other potential factors of variation, such as the process of farrowing and the morphological changes of the mammary epithelium that occur during the 24 h postpartum. The experiment was conducted on 16 Large White (LW) and 56 Landrace (LR) × Large White (LR × LW) crossbred sows of mixed parities and their litters. Most farrowings were induced at 113 days of gestation and all farrowings were attended. Each piglet was weighed at birth and 24 h after farrowing started (t24). Colostrum ingestion by individual piglets was estimated using piglet weight gains from birth to t24. Colostrum production by sows was estimated by summing up colostrum intakes by each piglet of the litter. Colostrum was collected at the onset of farrowing (t0) and at t24 to determine concentrations of immunoglobulins G (IgG), Na and K. Analyses of correlations and multiple regressions were performed to identify the variables involved in variation of colostrum yield and IgG concentrations. Colostrum yield was not related to litter size and weight (P > 0.1). It was negatively correlated with the number of stillborn piglets (r = −0.33, P = 0.005) and within-litter variation of piglet birth weight (r = −0.24, P = 0.04). It was not related to the Na/K ratio in the colostrum, which is an indicator of the integrity of the mammary epithelium. When sows were categorised according to their level of colostrum yield, sows that produced a low yield of colostrum had more stillborn piglets at birth than the other sows (P < 0.05) and tended to have a longer birth interval during the early process of parturition (P < 0.1). At t24, concentrations of IgG in the colostrum were positively correlated with the Na/K ratio in the colostrum (r = 0.53, P < 0.001), which indicates the concomitance of the cessation of IgG transfer to the colostrum and the changes in the morphology of the mammary epithelium. This study points out the need for future research on the role of the hormones involved in both the process of parturition and lactogenesis in the relationship between stillbirth, process of parturition and colostrum production.
The objectives of this study were to investigate the effects of different dietary sources of unsaturated fatty acids (fish oil (FO) and/or linseed oil (LO)) on laying performance, egg yolk fatty acid composition, ovarian follicular development, antioxidative properties, immune response and tibial bone characteristics in aged laying hens. A total of 100 Hisex Brown hens at 56 weeks of age were housed individually in laying cages in an open-sided building under a 16 h light:8 h dark lighting schedule. Hens were randomly divided into four experimental treatments (n = 25 each). Birds were fed ad libitum diets containing 2.5% vegetable oil (C, control), 2.5% FO, 2.5% LO and a mixture of 1.25% LO +1.25% FO (LO + FO) from 56 to 68 weeks of age. Egg production, egg quality characteristics and yolk lipid profile were analyzed. At 68 weeks of age, ovarian follicles were classified and tibial bone characteristics were determined. Serum thiobarbituric acid reactive substance (TBARS), glutathione peroxidase (GSH-Px) activity and total antioxidant capacity were measured. Incorporation of n-3 polyunsaturated fatty acids (n-3PUFA) into the egg yolks has been successful by using dietary FO and/or LO. There were no significant effects of treatments on hen-day egg production, feed intake, egg weight, egg shape index, albumen height, Haugh units and yolk height. However, dietary FO and/or LO supplementation had a significantly positive effect on eggshell percentage, eggshell thickness and yolk color. At 68 weeks of age, there was no significant difference among dietary treatments for tibial bone measurements. Also, no negative effects were detected in ovarian follicular development and weights of the ovary and oviduct, expressed in both absolute terms and relative to body weight. Dietary 2.5% LO, 2.5% FO and a mixture of 1.25% FO + 1.25% LO enhanced GSH-Px activity, total antioxidant capacity and antibody titers significantly in comparison with control. It could be concluded that inclusion of mixed sources of n-3PUFA in diets at moderate levels (2.5%) increased the n-3PUFA content and decreased the n-6/n-3 ratio content in the yolk, improved the antioxidative status, reduced lipid peroxidation, enhanced the antibody response and did not have any negative influence on ovarian follicular development and tibial bone characteristics in aged laying hens.
Pannon White (n = 12) male rabbits (weight: 4050 to 4500 g, age: 9 months) received 2 ml of a suspension containing purified T-2 toxin by gavage for 3 days. The daily toxin intake was 4 mg/animal (0.78 to 0.99 mg/kg body weight (BW)). Control animals (n = 12) received toxin-free suspension for 3 days. Since a feed-refusal effect was observed on the second day after T-2 administration, a group of bucks (n = 10) were kept as controls (no toxin treatment) but on a restricted feeding schedule, that is, the same amount of feed was provided to them as was consumed by the exposed animals. On day 51 of the experiment (i.e. 48 days after the 3-day toxin treatment), semen was collected, and pH, concentration, motility and morphology of the spermatozoa, as well as concentration of citric acid, zinc and fructose in the seminal plasma, were measured. After gonadotropin-releasing hormone (GnRH) analogue treatment, the testosterone level was examined. One day of T-2 toxin treatment dramatically decreased voluntary feed intake (by 27% compared to control, P < 0.05) and remained lower (P < 0.05) during the first 2 weeks after the withdrawal of the toxin. BW of the contaminated rabbits decreased by 88% on days 17 and 29 compared to controls (P < 0.05). No effect of toxin treatment was detected on pH and quantity of the semen or concentration of spermatozoa. The ratio of spermatozoa showing progressive forward motility decreased from 65% to 53% in the semen samples of toxin-treated animals compared to controls (P > 0.05). The ratio of spermatozoa with abnormal morphology increased (P < 0.05) in the ejaculates collected from the toxin-treated animals. T-2 toxin applied in high doses decreased the concentration of citric acid in seminal plasma (P < 0.05). No effect of T-2 toxin on the concentrations of the other seminal plasma parameters (fructose and zinc) was observed. T-2 toxin decreased the basic testosterone level by 45% compared to control (P < 0.01) and resulted in lower (P < 0.05) GnRH-induced testosterone concentration. Feed restriction, that is, less nutrient intake, resulted in more morphologically abnormal spermatozoa in the semen, but it did not cause significant loss in BW, motility of the spermatozoa, composition of the seminal plasma or testosterone concentration – its effect needs further examination.
The aim was to determine the effect of orally administered ovine serum immunoglobulin (Ig) on growth performance, organ weight, gut morphology and mucin production in the Salmonella enteritidis – gavaged growing rat. Four groups consisted of non-gavaged rats fed a casein-based control basal diet (BD) and three groups of rats gavaged with 1 × 107 CFU S. enteritidis and fed a casein-based diet, a diet containing freeze-dried ovine Ig (FDOI) or a casein-based diet containing inactivated ovine Ig (IOI). The rats were randomly allocated to one of the four groups (n = 15/group) and received their respective diets for an 18-day experimental study. Gavaging took place on day 15. Average daily gain and body gain : feed ratio (post-gavage, 3 days) were significantly (P < 0.05) higher for the Salmonella-challenged rats fed the FDOI diet compared to those fed the BD and IOI diets. At the end of the study, the small intestine and colon were significantly (P < 0.05) heavier for the gavaged rats fed the FDOI diet compared to the gavaged rats fed either the BD or IOI diet. Moreover, the relative weights of the caecum, liver and spleen of the gavaged rats fed the BD or IOI diet were significantly (P < 0.05) heavier compared to the gavaged rats fed the FDOI diet. Generally, the gavaged rats fed the FDOI diet had significantly (P < 0.05) higher goblet cell counts and luminal mucin protein contents than the gavaged rats fed either the BD or IOI diet and had a more functional gut morphology. Overall, the FDOI fraction prevented the acute effects of S. enteritidis.
The aim of this experiment was to evaluate the impact of selection for greater muscling on whole body insulin responsiveness in cattle, as reflected by greater uptake of glucose in response to constant insulin infusion and greater glucose disappearance following an intravenous glucose tolerance test. This study used 18-month-old steers from an Angus herd visually assessed and selected for divergence in muscling over 15 years. Eleven high-muscled (High), 10 low-muscled (Low) and 3 high-muscled steers, which were heterozygous for a myostatin polymorphism (HighHet), were infused with insulin using the hyperinsulineamic-euglyceamic clamp technique. Insulin was constantly infused at two levels, 0.6 μIU/kg per min and 6.0 μIU/kg per min. Glucose was concurrently infused to maintain euglyceamia and the steady state glucose infusion rate (SSGIR) indicated insulin responsiveness. An intravenous glucose tolerance test was also administered at 200 mg/kg live weight. Sixteen blood samples were collected from each animal between −30 and 130 min relative to the administration of intravenous glucose, plasma glucose and insulin concentration was determined in order to analyse insulin secretion and glucose disappearance. Insulin-like growth factor-1 (IGF-1) was also measured in basal plasma samples. At the low insulin infusion rate of 0.6 mU/kg per min, the SSGIR was 73% higher for the High muscling genotype animals when compared to the Low (P < 0.05). At the high insulin infusion rate of 6.0 mU/kg per min, these differences were proportionately less with the High and the HighHet genotypes having only 27% and 34% higher SSGIR (P < 0.05) than the Low-muscled genotype. The High-muscled cattle also had 30% higher plasma IGF-1 concentrations compared to the Low-muscled cattle. There was no effect of muscling genotype on basal insulin or basal glucose concentrations, glucose disappearance or insulin secretion following an intravenous glucose tolerance test. The increased whole body insulin responsiveness in combination with higher IGF-1 concentrations in the High-muscled steers is likely to initiate a greater level of protein synthesis, which may partially explain the increased muscle accretion in these animals.
The objective of this study was to analyze differences in thermoregulation and water balance under conditions of heat load and water restriction between fat-tailed sheep (S) and Kacang goats (G). The daily intakes of food and water, daily outputs of urine and feces, rectal temperature, respiration rates, hematocrit values and plasma volumes of five shorn S and five G were determined over 10 days of four consecutive experimental conditions: (1) indoor – unrestricted water; (2) indoor – restricted water; (3) 10 h sunlight exposure – unrestricted water; and (4) 10 h sunlight exposure – restricted water. There was a 6- to 7-day adjustment period between two consecutive conditions. The study was conducted during the dry season. The animals were placed in individual cages, fed chopped native grass ad libitum and had free access to a urea–molasses multi-nutrient block. Under sunlight exposure with unrestricted water availability, S and G record an increase in the maximum rectal temperatures from 39.2°C to 40.2°C and from 39.9°C to 41.8°C, respectively. The thermoregulatory strategy used by S for maintaining a lower rectal temperature mostly depends on increasing the respiration rate as the main cooling mechanism. On the other hand, G apparently used sweating as the predominant mechanism for cooling. Moreover, G seemed to be more tolerable to higher heat storage and body temperature than S with a significant increase in plasma volume (P < 0.01), and this may be beneficial to the animals for the prevention of water loss. Under restricted water condition in either indoor or outdoor environment, both species decreased their plasma volume significantly, but rectal temperatures were relatively maintained. In all experimental conditions, the daily total water exchanges (ml/kg0.82 per day) of S were significantly higher than G (P < 0.01). However, when the percentages of the total daily water exchange were considered, the water lost through urination (38% to 39%), defecation (11% to 14%) and evaporation (46% to 49%) by S and G was not significantly different. Therefore, the results from this study clearly showed that S and G have different homeostatic strategies for the regulation of body temperature and fluid to cope with heat load and water restriction. These differences may have an important impact on the production management of S and G.
Exposure of anoestrous ewes to rams induces an increase in LH secretion, eventually leading to ovulation. This technique therefore is an effective, low-cost and hormone-free way of mating sheep outside the breeding season. However, the use of this technique is limited by the variability of the ewes’ responses. In this study, our objective was to understand more completely the origins of this variability and to determine the relative roles of breed, the point in time during anoestrus and the depth of anoestrus on the response to the ‘ram effect’. In the first experiment, the pattern of anoestrus on the basis of the concentration of progesterone determined weekly, was determined in four breeds including two less seasonal (Mérinos d'Arles and Romane), one highly seasonal (Mouton Vendéen) and one intermediate (Île-de-France) breeds. Anoestrus was longer and deeper in Mouton Vendéen and Île-de-France than in Romane or Mérinos d'Arles. In the second experiment, we used the same four breeds and tested their hypophyseal response to a challenge with a single dose of 75 ng gonadotrophin-releasing hormone (GnRH) in early, mid and late anoestrus, and then we examined their endocrine and ovarian responses to the ‘ram effect’. Most (97%) ewes responded to GnRH and most (93%) showed a short-term increase in LH pulsatility following the ‘ram effect’. The responses in both cases were higher in females that went on to ovulate, suggesting that the magnitude of the hypophyseal response to a GnRH challenge could be a predictor of the response to the ‘ram effect’. As previously observed, the best ovarian response was in Mérinos d'Arles at the end of anoestrus. However, there was no relationship between the proportion of females in the flock showing spontaneous ovulation and the response to the ‘ram effect’ of anoestrous ewes from the same flock.
Colostrum intake from birth to 24 h after the onset of parturition (T24) was estimated for 526 piglets from 40 litters. Plasma concentrations of immunoglobulin G (IgG), lactate, glucose and cortisol were determined at T24 for six piglets per litter. Plasma IgG concentration was also assayed at weaning (28 days) on the same piglets. Rectal temperature was measured at T24 on all piglets. Mortality was recorded until weaning and comparisons were made between piglets that died before weaning and those that were still alive at weaning. The piglets that died before weaning had lower birth weight, lower colostrum intake, lower weight gain between birth and T24, and had a lower rectal temperature, higher plasma cortisol concentration and lower plasma IgG and glucose concentrations at T24 than piglets still alive at weaning. In addition, a higher proportion of piglets that died before weaning had difficulty taking their first breath after birth and were affected by splayleg. Considering all piglets, colostrum intake was positively related to rectal temperature and plasma glucose concentration and negatively related to plasma cortisol concentration at T24. Plasma IgG concentration at T24 was explained by colostrum intake, IgG concentration in the ingested colostrum, birth weight and birth rank (P < 0.0001). Plasma IgG concentration at weaning was related to plasma IgG concentration at T24 (r = 0.54; P < 0.0001) and to colostrum intake (r = 0.32; P < 0.0001). Finally, body weight was explained by colostrum intake, birth weight and age until 6 weeks of age (P < 0.0001). These results show that colostrum intake is the main determinant of piglet survival through provision of energy and immune protection and has potential long-term effects on piglet growth and immunity.
The objective of this study was to identify possible risk factors for poor cow hind limb cleanliness in Danish loose-housed, lactating dairy cows. The study was conducted as a cross-sectional study of 1315 cows in 42 commercial Danish dairy herds with primarily Danish Holstein cows. The effect of four cow-level factors (parity, days in milk, daily lying time and lameness) and eight herd-level factors (herd size, milk production, milking system, floor type, access to pasture grazing, floor scraping frequency, hoof bathing frequency and hoof washing frequency) on the risk of having dirtier hind limbs were analysed using ordinal logistic regression fitting a proportional odds model. Cow hind limb cleanliness was scored using an ordinal score from 1 to 4: 1 being clean and 4 being covered in dirt. The odds ratios (ORs) estimated from the proportional odds model depict the effect of a risk factor on the odds of having a higher rather than a lower cleanliness score. First parity cows had an increased risk of being dirtier compared with third parity or older cows (OR = 1.70). Compared with late lactation, early and mid lactation were associated with an increased risk of being dirtier (OR = 2.07 and 1.33, respectively). Decreasing the daily time lying by 30 min was associated with an increased risk of being dirtier (OR = 1.05). Furthermore, an increased risk of being dirtier was found in herds with no pasture access (OR = 3.75).
The objective of this study was to evaluate the effects of three alternative (ALT) rearing systems for growing pigs (outdoor: 150 m2/pig; straw bedding: 1.30 m2/pig; and hut with access to a courtyard: 1.30 m2/pig) compared with a conventional system (fully slatted floor: 0.65 m2/pig, considered as control), on pre-slaughter stress indicators in relation with meat quality. To that end, the number of skin lesions on whole carcasses, as well as blood creatine kinase (CK) activity and urine levels in cortisol and catecholamines (adrenaline and noradrenaline) were determined at slaughter. Glycolytic potential (GP) and ultimate pH of the semimembranosus muscle were also measured. The global correlation network calculated between all these parameters shows that the indicators of pre-slaughter muscle activity (plasma CK) and/or stress indicators (e.g. adrenaline) are negatively (r = −0.26, P < 0.01; r = −0.29, P < 0.05, respectively) correlated with muscle GP and positively (r = 0.17, P < 0.05; r = 0.44, P < 0.001, respectively) with meat ultimate pH. Although some traits measured were sensitive to the degree of pre-slaughter mixing, they differed across rearing systems. The differences were most pronounced for the comparison of outdoors v. slatted floor. The lower levels of plasma CK and urinary catecholamines, and the lower number of carcass skin lesions of pigs reared outdoors, were related to a lower meat ultimate pH. Thus, ALT rearing systems influence animal welfare and meat quality, by providing enriched environmental conditions to the animals.
Dairy herd size is expected to increase in many European countries, given the recent policy changes within the European Union. Managing more cows may have implications for herd performance in the post-quota era. The objective of this study was to characterise spring-calving herds according to size and rate of expansion, and to determine trends in breeding policy, reproduction and production performance, which will inform industry of the likely implications of herd expansion. Performance data from milk recording herds comprising 775 795 lactations from 2555 herds for the years 2004 to 2008 inclusive were available from the Irish Cattle Breeding Federation. Herds were classified into Small (average of 37 cows), Medium (average of 54 cows) and Large (average of 87 cows) and separately into herds that were not expanding (Nil expansion), herds expanding on average by three cows per year (Slow expansion) and herds expanding on average by eight cows per year (Rapid expansion). There was no association between rate of expansion and 305-day fat and protein yield. However, 305-day milk yield decreased and milk protein and fat percentage increased with increasing rate of expansion. There were no associations between herd size and milk production except for protein and fat percentage, which increased with increasing herd size. Average parity number of the cows decreased as rate of expansion increased and tended to decrease as herd size increased. In rapidly expanding herds, cow numbers were increased by purchasing more cattle. The proportion of dairy sires relative to beef sires used in the breeding programme of expanding herds increased and there was more dairy crossbreeding, albeit at a low rate. Similarly, large herds were using more dairy sires and fewer beef sires. Expanding herds and large herds had superior reproductive performance relative to non-expanding and small herds. Animals in expanding herds calved for the first time at a younger age, had a shorter calving interval and were submitted for breeding by artificial insemination at a higher rate. The results give confidence to dairy producers likely to undergo significant expansion post-quota such that, despite managing more cows, production and reproductive performance need not decline. The management skills required to achieve these performance levels need investigation.
Today, different analytical methods are used by different laboratories to quantify androstenone in fat tissue. This study shows the comparison of methods used routinely in different laboratories for androstenone quantification: Time-resolved fluoroimmunoassay in Norwegian School of Veterinary Science (NSVS; Norway), gas chromatography coupled to mass spectrometry in Co-operative Central Laboratory (CCL; The Netherlands) and in Institut de Recerca i Tecnologia Agroalimentàries (IRTA; Spain), and high-pressure liquid chromatography in Agroscope Liebefeld-Posieux Research Station (ALP; Switzerland). In a first trial, a set of adipose tissue (AT) samples from 53 entire males was sent to CCL, IRTA and NSVS for determination of androstenone concentration. The average androstenone concentration (s.d.) was 2.47 (2.10) μg/g at NSVS, 1.31 (0.98) μg/g at CCL and 0.62 (0.52) μg/g at IRTA. Despite the large differences in absolute values, inter-laboratory correlations were high, ranging from 0.82 to 0.92. A closer look showed differences in the preparation step. Indeed, different matrices were used for the analysis: pure fat at NSVS, melted fat at CCL and AT at IRTA. A second trial was organised in order to circumvent the differences in sample preparation. Back fat samples from 10 entire males were lyophilised at the ALP labortary in Switzerland and were sent to the other laboratories for androstenone concentration measurement. The average concentration (s.d.) of androstenone in the freeze-dried AT samples was 0.87 (0.52), 1.03 (0.55), 0.84 (0.46) and 0.99 (0.67) μg/g at NSVS, CCL, IRTA and ALP, respectively, and the pairwise correlations between laboratories ranged from 0.92 to 0.97. Thus, this study shows the influence of the different sample preparation protocols, leading to major differences in the results, although still allowing high inter-laboratory correlations. The results further highlight the need for method standardisation and inter-laboratory ring tests for the determination of androstenone. This standardisation is especially relevant when deriving thresholds of consumer acceptance, whereas the ranking of animals for breeding purposes will be less affected due to the high correlations between methods.
Intensively finishing cattle on a high-grain diet is generally used to enhance marbling, whereas extensively finishing on grass is known to provide improved muscle fatty acid profiles. The objective of this study was to evaluate to what extent intensive concentrate finishing (0, 1 or 2 months) can be combined with forage feeding without negatively affecting the fatty acid profile of genetically lean animals. Bulls from the ‘Asturiana de los Valles’ breed were reared under grazing conditions with/without final finishing on a barley-based concentrate: 0 months (control; n = 7), 1 month (n = 10) and 2 months (n = 7). Yearling bulls were slaughtered commercially at an average live weight of 516 ± 9.8 kg. Increasing the finishing time on concentrate significantly increased the saturated and monounsaturated fatty acids, whereas polyunsaturated fatty acids (PUFAs) tended to decrease and it was not possible to increase the long-chain PUFA content in muscle tissue of this breed. An increase was observed for total trans-18:1 (average 5.5% with grain v. 3.7% for grass). The 11t-18:1/10t-18:1 ratio was significantly higher in grass-fed (average 8.1) compared with grain-finished animals (average 1.1). Grass or limited concentrate finishing reduced the n-6/n-3 ratio in muscle tissue (average 3.6 for 0 and 1 month, and 4.9 for 2 months on grain finishing). The beef was within or close to the recommended values for human consumption (i.e. polyunsaturated/saturated > 0.45, n-6/n-3 < 4.0), and total trans-FA content was low. However, finishing increased the content of undesirable trans-18:1 and conjugated linoleic acid isomers, particularly after 2 months, whereas grass finishing was judged to provide a healthier beef fatty acid profile.
Mid-infrared spectroscopy (MIR) is used to predict fatty acid (FA) composition of individual milk samples (n = 267) of Brown Swiss cows. FAs were analyzed by gas chromatography as a reference method. Samples were scanned (4000 to 900 cm−1) by MIR, and predictive models were developed using modified partial least squares regressions with full cross-validation. The methods using a first derivative or multiplicative scatter corrected plus first derivative resulted, on average, in the best predictions. Coefficients of correlation between measured and predicted C8:0, C10:0, C12:0, C14:0, anteiso-C17:0, c9-C18:1, and medium- and long-chain FA, and saturated, monounsaturated and unsaturated FA ranged from 0.71 to 0.77, suggesting that prediction models can be implemented in milk recording schemes to routinely collect information on FA composition from the whole Brown Swiss population for breeding purposes.