Drinking preferences in chinchillas (Chinchilla laniger), degus (Octodon degu) and guinea pigs (Cavia porcellus)

Chinchilla (Chinchilla laniger), degus (Octodon degus) and guinea pigs (Cavia porcellus) are South American rodents living in a semi‐arid habitat with varying, species‐specific adaptations to water deprivation. Nonetheless, several diseases have been linked to insufficient water intake when these species are kept as pets, such as urolithiasis or obstipation. This study evaluated preferences for drinking systems. Six animals of each species were given a choice between an open dish and a nipple drinker. Food intake and water intake were measured daily for 13 days. Chinchillas in this study had significantly lower water intakes than the other two species, indicating particular species‐specific adaptations to aridity. All chinchillas favoured open dishes, whereas the degus and guinea pigs had variable individual preferences. Water intake of chinchillas was similar or higher in this study than in previous studies where nipple drinkers were used. The results indicate that degus and guinea pigs can meet their drinking water needs with nipple drinkers; for chinchillas, other drinking systems may be more adequate.     

Guinea pig (Cavia porcellus) drinking preferences: do nipple drinkers compensate for behaviourally deficient diets?

When offered diets with hay ad libitum, rabbits (Oryctolagus cuniculus) clearly prefer open dishes over nipple drinkers, but whether this preference also applies in guinea pigs (Cavia porcellus) is unsure. We tested the drinker preference of 10 guinea pigs when offered open dishes (OD) and nipple drinkers (ND) simultaneously and measured the amount of water consumed by each animal on four different diets (grass hay 100%, or as 10% of intake on diets of fresh parsley, seed mix or pelleted complete feed, respectively) on either of the drinking systems. All animals ingested the hay portion of the combined diets first. The amount of water consumed differed significantly between individual animals. Animals drank less water on parsley than on the other diets. Nine of 10 animals clearly preferred ND when having a choice, and eight of these drank more when on ND only. The difference between the drinking systems was not consistent across all diets: on hay, similar amounts of water were drunk when on OD or ND only. Differences in water intake were reflected in urine production. Because drinking from ND in guinea pigs involves jaw movements similar to those in chewing, the results could suggest that when motivation for oral processing behaviour is not satisfied by a diet, animals may respond in using ND beyond physiological water necessity. Whereas physiological water requirements are probably better investigated with other drinking systems due to a possible overestimation when using ND, offering ND to pet guinea pigs most likely offers a form of behavioural enrichment that at the same time may increase water intake and hence act as prophylaxis against urolithiasis.     

Water intake and wastage at nipple drinkers by growing-finishing pigs

Three experiments were conducted to assess water intake, water wastage, and a means to decrease water wastage by growing-finishing pigs from nipple drinkers. In Exp. 1, 48 pigs were studied during two periods (average BW = 53 and 72 kg for Period 1 and 2, respectively). Water disappearance and wastage were determined for 4 d, while nipple drinkers were set at 50 mm above the shoulder height of the smallest pig in the pen (recommended heights), with flow rates at 700 mL/min during Period 1, and 1,000 mL/min during Period 2. Water intake rate was assessed at two nipple flow rates, approximately 650 and 1,300 mL/min during the Period 1, and 1,000 and 2,000 mL/min during the Period 2. The average water intake was 4.01 and 5.38 +/- 0.19 L.pig(-1).d(-1) during Periods 1 and 2, respectively (P < 0.01). Water wastage as a percentage of water disappearance was similar between the two periods (25.8 and 27.0 +/- 1.9% for Periods 1 and 2, respectively). Water intake rate was 467 and 795 mL/min (+/-34.2; P < 0.01) during Period 1, and 722 and 1,422 mL/min (+/-80.0; P < 0.01) during Period 2, at the lower and higher flow rates, respectively. In Exp. 2, 32 pigs were used in a 2 x 2 factorial design to determine effects of nipple heights (recommended vs. unadjusted = 330 mm) and flow rates (500 vs. 1,000 mL/min) on water intake and wastage. Water wastage was increased (P < 0.01) on the unadjusted vs. recommended nipple height, and the higher flow rate also resulted in greater wastage (P = 0.03) compared with the lower rate. In Exp. 3, water disappearance and manure output in 16 pens of 18 pigs per pen were monitored for 12 wk (average initial BW = 32 kg) using four drinker treatments (bowl drinker, nipple drinker at recommended heights, an unadjusted nipple set at 480 mm, and high nipple drinker height of 730 mm with a step underneath). For pigs on the high nipple drinker, the average water disappearance and manure output did not differ from those of the pigs on the recommended nipple heights and bowl drinker, but these measurements were 15 and 12% lower, respectively, than for the pigs on the low nipple drinker. The results indicate that growing-finishing pigs can maintain adequate water intake from a variety of drinker types and management. Water wastage can be controlled through drinker management.     

Effect of drinker type and sound stimuli on early-weaned pig performance and behavior

Early-weaned pigs appear to be highly motivated to engage in motor patterns associated with nursing, which is thought to lead to the development of abnormal ingestive behaviors. If performance of these behaviors is related to sucking motivation, then the normal stimuli associated with nursing should stimulate pigs to perform these abnormal behaviors, specifically belly nosing. The goal of this study was to determine whether belly nosing could be affected by sow nursing vocalizations and whether the style of the drinker device influenced early-weaned pig behavior. Over six trials, 352 Yorkshire pigs were weaned at 15 d and assigned to pens (n = 44) of eight pigs based on litter, weight, and sex. Four pens in each of two rooms were outfitted with either a water nipple drinker or a drinker bowl. Rooms either had recorded sow vocalizations broadcast at hourly intervals or no sound (control). Pig behaviors were videotaped in a sample of pens (n = 32) on d 0, 1, 2, 5, 9, 11, 13, 16, and 18 after weaning. On d 0 to 2, pigs were observed continuously for feeding and drinking behaviors. On d 5 to 18, pigs were observed by scan sampling every 5 min for time budgets. Pigs with drinker bowls had higher apparent feed intakes during the first 2 d after weaning (P = 0.024), whereas they spent less time engaged in drinking behavior (P = 0.001). This coincided with an overall lower water use (P = 0.001) than that of pigs with nipple drinkers. Pigs with bowl drinkers also spent less time belly nosing than those with access to a nipple drinker (P = 0.012). Pigs in the sow vocalization treatment tended to have a higher ADG (P = 0.075), whereas they spent less time performing feeding behavior (P = 0.064). However, there was no effect of sow nursing grunts on belly nosing. These results suggest that there is a complex relationship between feeding, drinking and sucking, and belly nosing is not controlled by the same external stimuli as sucking. Because drinker type and the motor patterns that it accommodates affect belly nosing, it may be that the internal stimuli associated with nursing, such as the actual act of sucking, play a large role in the development of abnormal oral-nasal behaviors.     

Effect of drinker type on water intake and waste in newly weaned piglets

During the first few days after weaning, pigs often experience BW loss as they adapt to eating solid food. During this time period, they are also known to drink excessively and develop abnormal oral behavior such as belly nosing. The excessive drinking may stem from the piglets' attempt to satiate hunger through gut fill from a familiar ingestive source. Gut fill through water intake may affect the establishment of feeding behavior. Using drinker devices other than the standard nipple drinker may ease the piglets' transition at weaning by facilitating the initiation of feeding and preventing the development of behavioral problems such as excessive drinking and belly nosing. In this experiment, we examined the effect of drinker type on water and food intake, growth rates, and belly nosing in newly weaned piglets. Eighteen pens of 15 piglets each (270 piglets total) were weaned at 18.1 +/- 0.1 d of age and housed in pens containing 1 of 3 drinker devices (standard nipple, push-lever bowl, and float bowl). Piglets' water and feed intake, water use, BW, and behavior were examined on a pen basis through 2 wk after weaning. Piglets with nipple drinkers wasted more water than the other piglets (P < 0.001; float, 295 +/- 70 mL x pig(-1) . d(-1); nipple, 1,114 +/- 63 mL x pig(-1) . d(-1); and push-lever, 186 +/- 63 mL x pig(-1) . d(-1)), whereas piglets with float bowls consumed less water than the other piglets (P < 0.001; float, 475 +/- 81 mL . pig(-1) x d(-1); nipple, 870 +/- 76 mL x pig(-1) . d(-1); push-lever, 774 +/- 76 mL x pig(-1) . d(-1)). Drinker type affected feeding behavior (P = 0.02); piglets with push-lever bowls spent less time at the feeder than the other piglets, although no difference was detected for feed intake (P = 0.64) or overall ADG (P = 0.16). Piglets with push-lever bowls also tended to perform less piglet-directed nosing behavior than piglets with the float bowl (P = 0.04). Piglets appear to use more water during the first 2 d after weaning with certain drinker devices. However, piglets do not appear to attain satiety through water consumption because most of the water used during the first few days after weaning is wasted. This excessive drinking and water wastage can be abated through the use of push-lever drinkers without negative implications for feed intake or growth rates.     

Water intake in domestic rabbits (Oryctolagus cuniculus) from open dishes and nipple drinkers under different water and feeding regimes

Rabbits (Oryctolagus cuniculus) are often presented suffering from urolithiasis. A high water intake is important in the prophylaxis of uroliths. We investigated the influence factors for water intake using 12 rabbits subjected to different feed and water regimes with practical relevance: Hay, fresh parsley, a seed mix and two different pelleted feed were offered in diverse combinations. Water was provided either by open dish or nipple drinker. Water was accessible ad libitum except for four treatments with 6 h or 12 h water access. Under the different feeding regimes, the drinker had no influence on water intake, but faecal dry matter content was significantly higher with nipple drinkers [60.0 ± 2.1 vs. 57.2 ± 2.1% of wet weight (mean ± 95% confidence interval), p = 0.003]. Dry food led to a higher drinking water intake but total water intake was still lower than with addition of 'fresh' food. With restricted water access, rabbits exhibited a significantly higher water intake with open dishes compared with nipple drinkers (54.9 ± 9.8 vs. 48.1 ± 8.2 g/kg(0.75) /day (mean ± 95% confidence interval), p = 0.04). High proportions of fresh parsley or hay in the diet enhanced total water intake and urine output, and led to lower urinary dry matter content and lower urinary calcium concentrations. Restricted access to drinkers led to a decreased total daily water intake and increased dry matter content of urine and faeces. For optimal water provision and urolith prophylaxis, we recommend a diet with a high 'fresh food' proportion as well as additionally hay ad libitum with free water access, offered in an open bowl.     

Epidemiological associations between characteristics of registered broiler chicken flocks in Canada and the Salmonella culture status of floor litter and drinking water

A Canada-wide flock management survey of 294 randomly selected commercial broiler chicken flocks was conducted during 1989-1990. The prevalence of flocks that yielded Salmonella from cultures of floor litter or drinking water, and the prevalence of floor litter samples that yielded Salmonella, were significantly associated (p < 0.05) with the age of the flock and the region of Canda in which the flock was located. Culture of Salmonella from the drinking water was significantly associated (p < 0.05) with the type of drinker used, the dead bird disposal method, and the region of Canada in which the flock was located. There was a significantly greater risk (p < 0.05) of contamination of drinking water with Salmonella from trough drinkers (odds ratio = 7.99) and plastic bell drinkers (odds ratio = 6.10) than from nipple drinkers. No significant associations were found between pest control, restrictions on visitors, clean-out methods, or water sanitization and the culture of salmonellae from floor litter or drinking water.     

Analysis of polymorphisms of cathepsin B and cystatin B impact on economically important traits in pigs raised in Poland

The cathepsins belong to an enzyme family of lysosomal proteinases, which have a wide spectrum of function in a lot of tissues and cell types. Cathepsin B is one of intracellular proteases, whose role is to carboxydipeptidyl activity. In turn, the cystatin B (CSTB) is an intracellular thiol proteinase inhibitor. In pigs, CTSB was mapped on 14 chromosome and linked to loci genes ATP2A2, ACTN2 and ACTA1, in the region where suggestive QTL for fat deposition and meat content were identified. The CSTB gene is localized on telomeric end (1/2) q46–q49 of SSC13 and on this chromosome QTLs for daily gain and birth weight were identified. Our investigation concerned analysis of effects A72C CTSB polymorphism and Asp62Asn CSTB missense mutation on carcass traits in Polish pigs population. The significant results of A72C of CTSB mutation was observed for several growth traits in Pietrain pigs. AC genotype characterized higher carcass yield and weight of ham and loin than in AA pigs (AC — 79.3%, 6.90 kg and 10.2 kg; AA — 77.8, 6.52 and 9.89, P < 0.01). The significant effect of Asp62Asn CSTB was in two traits of Polish Large White pigs: AA animals had higher daily gain and lower number days in test compared to animals with GG genotype (AA — 973 g, 162 days; GG — 882 g, 172 days) with favorable additive genetic effects of allele g173A on LSM. The selection on A allele of CSTB should lead to increasing level of fat. In turn, increasing in population, a C allele of CTSB should affect better meat content parameters in pig population. Overall, these two polymorphisms seem not to be directly association with carcass traits, but probably are linked to unknown QTLs localized on 13 and 14 chromosomes.     

Effect of environment on Pekin duck behaviour and its correlation with body condition on commercial farms in the UK

1.?Forty-six flocks of commercially-reared Pekin ducks were studied to determine the effects of housing system and environment on the behaviour of farmed ducks and its correlation with physical condition. Houses differed predominantly in their ventilation, drinking, feeding and brooding systems, and were indicative of systems currently in use in the UK.

2.?At 41 d of age ducks spent 1?5% of the time feeding, 6?7% drinking, 4?2% rooting and 15?5% dry preening. They spent large amounts of time relatively inactive, 43?5%, or performing comfort behaviours, 17%. On average 4?6% of their time was spent walking and only 1?8% wet preening.

3.?A greater proportion of the maximum number of ducks able to use the drinker at any one time used the trough; nipple use was least and Plasson use intermediate. The proportion of ducks wet preening was not affected by drinker type but increased with increasing drinker space (mm/bird).

4.?Duck behaviour was little affected by commercial production system and was influenced more by environment, age and physical condition. Activity at an older age incorporated more of the behaviours associated with thermal comfort (panting) and maintenance of plumage condition (dry and wet preening). These behaviours increased with increasing temperature, relative humidity and atmospheric ammonia. Poor walking ability was correlated to increased frequency of panting, reduced activity at the drinker, and longer resting bouts.     

Effects of regrouping, feeding and drinking methods on weight gain of weaned piglets

The effects of alterations in regrouping, feeding and drinking practices were examined on a pig farm to improve animal welfare and productivity. Weaned at 35 days of age, 720 piglets were randomly assigned to 24 groups of 30 piglets in a factorial design with three factors. During the next 55 days they were regrouped once, twice or not regrouped at all, had nipple drinkers or a water trough and had 3, 6 or 10 cm trough length per animal and four meals a day or 3 cm trough length per animal and six daily meals. Simple factorial ANOVA revealed that the piglets grew very highly significantly (p < 0.001) faster if they were not regrouped, drank from water troughs and had sufficient trough length available, however, increased feeding frequency partially compensated for shorter trough length. Similar analysis of the ranges of body weights within groups showed similar, yet less significant effects in the opposite direction, i.e. where pigs grew faster there tended to be also less weight difference. It is concluded that avoidance of mixing and undisturbed, easy access to food and water is beneficial to both the welfare of the pigs as well as their productivity.     

Effect of chlorination of drinking water on experimental salmonella infection in poultry

The type of drinker used for poults influenced the level of free available chlorine (FAC) in chlorinated water as well as the total plate count, fecal coliform count, and number of salmonellae in chlorinated and non-chlorinated drinking water. Nipple drinkers maintained higher levels of FAC in drinking water than Swish-cups, Swish-cups maintained higher levels than MarkIII, and MarkIII maintained higher levels than trough drinkers. The level of FAC retained in the water in trough drinkers was insufficient to exert a bactericidal effect against coliforms and salmonellae. Chlorination of drinking water and the resulting diminished number or absence of salmonellae in the drinking water did not lower the number of salmonellae per gram of cecal contents in challenged or unchallenged but exposed poults. The number of salmonellae per gram of cecal contents decreased significantly (P less than 0.01) in poults between 14 and 21 days of age, irrespective of whether or not the poults drank chlorinated water.     

Performance,meat quality,meat mineral contents and caecal microbial population responses to humic substances administered in drinking water in broilers

1. This study was conducted to examine the effect of different levels of humic substances (HS) administered in drinking water on caecal microflora and mineral composition and colour characteristics of breast and thigh meats and the growth performance, carcass and gastrointestinal tract (GIT) traits of broiler chicks.

2. A total of 480 3-d-old broiler chickens were randomly allocated to 4 treatments with 4 cages per treatment and 30 bird (15 males and 15 females) chicks per cage. All birds were fed on commercial basal diet. The control birds (HS0) received drinking water with no additions, whereas birds in the other treatment groups received a drinking water with 7.5 (HS7.5), 15.0 (HS15.0) and 22.5 (HS22.5) g/kg HS. Mush feed were provided on an ad libitum basis. Body weight and feed intake of broilers were determined at d 0, 21, and 42, and feed conversion ratio was calculated. On d 42, 4 broilers (2 males and 2 females) from each cage were slaughtered and the breast and thigh meats were collected for mineral composition and quality measurements.

3. Performance, carcass and GIT traits and caecal microbial population of broiler chicks at d 42 were not affected by the dietary treatments. The lightness (L*) of breast and thigh meat decreased in broilers supplemented with 15 and 22.5 g/kg HS in drinking water. Although the redness (a*) of breast meat increased, yellowness of thigh meat decreased in broilers supplemented with 15 and 22.5 g/kg HS in drinking water (P < 0.05).

4. In conclusion, the 15 and 22.5 g/kg HS administration in drinking water can be applied for broiler chicks to maintain growth performance and improve meat quality without changing caecal microflora.     

宁乡猪及杜宁二元杂种猪的胴体与肉质性状测定

为评价宁乡猪和杜洛克猪的杂交效果,本实验分别测定了91头宁乡猪和76头杜宁二元杂种猪的胴体性状和肉质性状指标,并对不同性状指标进行相关性分析。结果表明:在胴体性状方面,与宁乡猪相比,杜宁二元杂种猪的体直长、体斜长、胴体重、肋骨数和眼肌面积极显著提高,背膘厚和皮厚极显著降低;在肉质性状方面,杜宁二元杂种猪的肉色红度(a^*)、pH_45min和熟肉率极显著高于宁乡猪,pH24h显著低于宁乡猪。相关性分析显示,宁乡猪体斜长和胴体重存在极显著正相关(r=0.71),a^*值与黄度(b^*)值之间存在高度正相关(r=0.58);杜宁二元杂种猪体直长与体斜长存在极显著正相关(r=0.64),亮度(L^*)值与b值极显著相关(r=0.54)。说明杜宁二元杂种猪在导入杜洛克血缘后,其胴体性状较宁乡猪得到较大改善,但肉质性状改善效果不明显。     

不同体重商品猪胴体性能肉质性状及其相关程度研究

研究测定了92～109 kg体重阶段31头杂交商品猪的胴体品质和肉质特性，以分析商品猪胴体、肌肉品质随体重的变化规律及其相关程度，为确定适宜上市屠宰体重提供依据。结果表明，商品猪在92～95 kg阶段屠宰瘦肉率最高为61.17％，分别比其它3组提高4.83％（P>0.05）、11.83％（P<0.05）和8.84％（P<0.05）；在107～109 kg阶段屠宰肉品质〖JP2〗优良，肌肉pH 6.07，肉色和大理石纹评分较高分别为3.13和 3.33，肌内脂肪含量较高为3.89％，肌肉失水率较低为18.91％。胴体和肉质性状间相关程度有强有弱，相关系数有正有负。相同性状间有较强的正相关，相反性状间有较强的负相关。综合分析试验结果认为，注重产肉量强调胴体瘦肉率时可选择在92～95 kg阶段屠宰；注重肉品质时可选择107～109 kg阶段屠宰；若二者兼顾则选择95~98 kg阶段屠宰较为合适。     

Back-fat thickness as a primary index reflecting the yield and overall acceptance of pork meat

Predicting aspects of lean meat yield and eating quality of pork based on some particular carcass traits become increasingly important from an economic profitability point of view. The present study aimed to determine the relationship between the back-fat (BF) thickness with lean meat yield and meat quality traits of crossbred pigs. A total of 220 crossbred pigs [(Landrace × Yorkshire) ♀ × Duroc ♂] reared under identical conditions and harvested at 180 days old were slaughtered and screened for BF thickness. Four BF thickness groups: 12–15, 16–20, 21–25, and 26–30 mm were classified, and longissimus dorsi (LD) muscles from these groups were used to analyze meat quality characteristics. Results showed that increasing BF thickness decreased the lean meat yield and loin lean area. Increasing BF thickness up to 26–30 mm increased intramuscular fat content and pH of LD muscles. The LD muscles of the thicker BF (21–30 mm) groups received significantly higher flavor, juiciness, and overall acceptability scores than those of the thinner back-fat (12–20 mm) groups. Overall, when all the pre-harvest factors are kept the same, BF thickness could be considered as a primary index for predicting lean meat yield, and the minimal back-fat thickness of 21–30 mm is required to improve the overall acceptability of pork meat.     

Effect of magnesium sulphate and l-tryptophan and genotype on the feed intake, behaviour and meat quality of pigs

Sixty-nine entire male pigs with different halothane genotype (homozygous halothane positive — nn-, n = 36; and homozygous halothane negative — NN-, n = 33) were fed with a supplementation of magnesium sulphate (Mg) and/or l-tryptophan (Trp) in the diet for 5 days before slaughter. Animals were housed individually and were submitted to stressful ante mortem conditions (mixed in the lorry according to treatments and transported 1 h on rough roads). Individual feed intake was recorded during the 5-d treatment. At the abattoir, pig behaviour was assessed in the raceway to the stunning system and during the stunning period by exposure to CO₂. Muscle pH, colour, water holding capacity, texture and cathepsin activities were determined to assess meat quality. The number of pigs with an individual feed intake lower than 2 kg/day was significantly different among diets (P < 0.05; Control: 8.7%; Mg&Trp: 43.5%; Trp: 17.4%) and they were considered to have inadequate supplement intake. During the ante mortem period, 15.2% of pigs included in the experiment died, and this percentage decreased to 8.7% in those pigs with a feed intake > 2 kg/day, all of them from the stress-sensitive pigs (nn). In general, no differences were observed in the behaviour of pigs along the corridor leading to the stunning system and inside the CO₂ stunning system. During the stunning procedure, Trp diet showed shorter periods of muscular excitation than control and Mg&Trp diets. The combination of a stressful ante mortem treatment and Mg&Trp supplementation led to carcasses with high incidence of severe skin lesions. Different meat quality results were found when considering all pigs or considering only those with adequate supplement intake. In this later case, Trp increased pH₄₅ (6.15) vs Control diet (5.96) in the Longissimus thoracis (LT) muscle (P < 0.05) and pH at 24 h (Trp: 5.59 vs C: 5.47) led to a higher incidence of dark, firm and exudative (DFD) traits in SM muscle (P < 0.05). Genotype affected negatively all the meat quality traits. Seventy-five percent of LT and 60.0% of the SM muscles from nn pigs were classified as pale, soft and exudative (PSE), while none of the NN pigs showed these traits (P < 0.0001). No significant differences were found between genotypes on the incidence of DFD meat.Due to the negative effects observed in the Mg&Trp group in feed intake and carcass quality, the utilization of a mixture of magnesium sulphate and tryptophan is not recommended.     

Effects of continuous stray voltage on health, growth and welfare of fattening pigs.

The effects of continuous stray voltage were evaluated on growing-finishing pigs between the ages of 8 and 21 weeks. Seventy-two pigs were assigned to six blocks of 12 animals each. The following treatments were randomly distributed in each block according to a 2 x 3 factorial design: feeding level (restricted or ad libitum) and voltage level (0, 2 or 5 volts (V) as a difference of potential between feeder or drinker and the metallic floor). During daytime, stray voltage at 5 V decreased (p less than 0.05) the eating frequency in both feeding groups and the drinking frequency in restricted-fed pigs. The mean duration of drinking bouts and the total time spent at the drinker were also lower (p less than 0.05) in this last group during the hour following meal distribution. Daily feed intake and average daily gain were lower (p less than 0.05 and less than or equal to 0.08, respectively) in the 5 V group than in the 2 V and the control groups from 17 to 21 weeks of age. Finally, gastric lesions, hematological and biochemical variables were not affected (p greater than 0.05) by stray voltage.     

The influences of weaning age and weight on carcass traits and meat quality of pigs

The purpose of this study was to establish the effects of weaning age and weight on pigs, and their interaction with carcass traits and meat quality. A total of 468 piglets were obtained from 57 sows and four boars and grouped by age at weaning (D21, 18–24 days; D28, 25–32 days). Each weaning group was subdivided into three weight groups (L, M and H) according to weaning weight. The D28 group had heavier carcass weight, redness and yellowness, but had lower marbling scores and less drip loss than the D21 group (P < 0.05). The pigs with a light weight at weaning had higher carcass weights and lower yellowness than did pigs with a medium or heavy weight at weaning (P < 0.05). Weaning age was found to have a negative correlation with drip loss, while weaning weight was negatively correlated with carcass weight and drip loss (P < 0.05). We concluded that carcass and meat quality traits in pigs were significantly related to their age and weight at weaning. Therefore, we find that piglet weaning age and weight are no less important than post‐weaning growth performance and behavior, with regard to carcass traits and meat quality.     

Exposure variability of fosfomycin administered to pigs in food or water: Impact of social rank

The objective of this study was to document the effect of social ranking on the internal exposure of pigs to an antibiotic (fosfomycin) administered either in food or in drinking water. Signs of aggression were recorded at the feeder and drinker. The interindividual variability explained by the social rank was even greater when the test antibiotic was given in food despite the fact that the water consumption was less variable than the food intake. The range of plasma concentrations after administration of fosfomycin either in food or drinking water leads to a number of pigs in the treated group being exposed to rather low and highly variable concentrations of fosfomycin and not able to maintain adequate plasma concentrations above the typical minimum inhibitory concentration (MIC). Social rank clearly influences the level of exposure of pigs to fosfomycin both in food and drinking. However, its administration in drinking water is likely to be the best option to optimize antibiotic efficacy.