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1.
Tail damage within the production of finisher pigs is an animal welfare problem. Recent research suggests that removal of known risk factors may not be enough to eliminate tail biting, especially in undocked pigs, thus a different strategy is worth investigating. This could be early detection of tail biting, using behavioural changes observed before tail damage. If these early stages of tail biting can be detected before tail damage occurs, then tail damage could be prevented by early interventions. The first step in developing such a strategy is to identify the types of behaviour changes that emerge during early stages of tail biting. Thus, the aim of the current study was to investigate whether pen level activity and object manipulation evolved differently during the last 7 days before the scoring of tail damage (day 0) for pens scored with tail damage (tail damage pens) and pens not scored with tail damage (matched control pens). The study included video recordings for twenty-four tail damage pens and thirty-two matched control pens. Activity level and object manipulation were observed the last 7 days before day 0 during the morning (0600 to 0800 h), afternoon (1600 to 1800 h) and evening (2200 to 2400 h, only activity level). Both activity level and object manipulation were analysed using generalised linear mixed effects models with a binomial distribution for activity level and a negative binomial distribution for object manipulation. The probability of being active was higher in tail damage pens compared to control pens during the afternoon the last 5 days before day 0 (P<0.001). This was seen due to a decrease in activity level in the control pens, which makes it difficult to identify future tail damage pens from this difference. Object manipulation was lower in tail damage pens compared to the control pens on all 7 days before day 0, but only in pens with undocked pigs (P<0.01). Thus, it is still unknown when this difference in object manipulation initiated. It was concluded that both activity level and object manipulation seemed related to ongoing tail biting and should be investigated through more detailed observations and for a longer time to establish the normal behaviour pattern for a particular pen. Thus, it is suggested that future research focusses on developing automatic monitoring methods for pen level activity and object manipulation and applies algorithms that establish and detect deviations from the normal behaviour pattern of the pen before tail damage.  相似文献   

2.
Common loons (Gavia immer) are diving waterbirds that are particularly challenging to keep in captivity due to their specific behavioral and physiologic needs, special housing requirements, and susceptibility to stress-related disease. We report a novel method for housing and captive rearing common loon chicks that was developed as part of the first-ever loon translocation effort in southeast Massachusetts, from 2015 to 2017. Thirteen loon chicks were reared in aquatic pens in a natural lake environment, utilizing noninvasive feeding and monitoring techniques that avoided human habituation. Chicks were reared in aquatic pens for 16–28 days before being released onto the lake. All chicks remained clinically normal and were monitored on the lake for up to 4 months following release. At least four of the chicks were subsequently confirmed to have survived to adulthood when they returned to the area in breeding plumage two to 3 years following release. Two of these confirmed adults displayed prolonged territorial pair behavior together, and this is an encouraging early sign that captive-reared individuals may form successful breeding pairs in the future. Because most immature loons remain on the ocean until at least 3 years of age, we expect additional captive-reared loons to return to the release area in subsequent years. These husbandry techniques could be applied to other loon and diving bird species that are notoriously difficult to house in captivity. The novel feeding techniques described here could also be adapted for loon chicks being reared in pools or other traditional captive settings.  相似文献   

3.
Abstract

Activity data from two experimental lizard groups were analysed in order to search for 24 h‐entrained and ultradian periodicities. The data of a first group were obtained through motion sensitive platforms situated under the animals’ cage and continuously for up to 12 consecutive days; those from a second group were collected by manual recording of the behaviour patterns of individual animals for 2 h each day over a 10‐day period. Lizards from both groups were situated in cages inside isolated chambers in which a light‐dark cycle (12:12), a temperature of 28°C ±1° and a relative humidity of 50–60% were maintained. Periodogram analysis showed the existence of a significant period peak (p < 0.01) at 24 h. Autocorrelation functions and spectral analysis of different data‐segment lengths showed that ultradian periodicities were present in the daily motor activity, appearing as noisy though frequency‐band limited. Differences in the frequency band‐limited fluctuations were found between morning and afternoon activities: during the morning ultradian activity appears distributed in two bands (4.5–36 c/day and 63–94 c/day), the power being mainly concentrated in the second one, while during the afternoon it was in the 4.5–36 c/day band. Results from the second lizard group showed only one band (24–60 c/day) overlapped with the first one from the latter group. Although activity recording methods and some experimental conditions are discussed as possible sources of these differences, the possibility of endogenous ultradian variation within the individuals is also suggested.  相似文献   

4.
Domestic chicks were exposed to a moving, stuffed jungle fowl or a rotating red box. The effects on the imprinting process of lesions to a restricted part of the hyperstriatum ventrale (IMHV) were studied in a series of experiments. Sham-operated control chicks developed a strong preference for the training object. Damage to IMHV impaired chicks' preferences for the training stimulus. However, the effect on chicks exposed to the red box was profound, whereas the effect on chicks exposed to the jungle fowl was relatively weak. The results suggest that information about a complex object, which in the experiments described resembled the chicks' own species, is stored in a different way from information derived from a relatively simple artificial object.  相似文献   

5.
Preferences of domestic chicks were studied either at approximately 2 h or approximately 24 h after exposure to a red box or a stuffed jungle fowl. Preferences of the chicks were measured in a simultaneous choice test involving these two stimuli. When tested at about 2 h, chicks preferred the object to which they had previously been exposed. Chicks tested at about 24 h showed a significantly greater preference for the jungle folw than those tested at about 2 h, regardless of the training stimulus. Birds that had been placed in a running wheel and exposed to diffuse light also showed an increasing preference for the fowl over time when tested in the same manner. These results may be accounted for in terms of an interaction between two processes, a developing predisposition for the fowl on the one hand and a preference acquired through learning on the other.  相似文献   

6.
In dairy calves kept in pens, lack of sufficient space may inhibit the performance of play behaviour. The present study investigated, firstly, if an increase in space allowance increases the occurrence of play behaviour, and secondly, if calves kept at a low space allowance perform more locomotor play when released individually in a large novel area. A total of 96 dairy calves in six repetitions were housed in groups of four, in pens of either 4, 3, 2.2 or 1.5 m(2) per calf from 2 weeks of age. The occurrence of play behaviour in the home environment was recorded continuously for each individual calf during 24 h at 5, 7 and 9 weeks of age. Locomotor play decreased over the weeks (54, 29 and 19 s for weeks 5, 7 and 9, respectively; F(2,40)=17.98; P<0.001), and the interaction between space allowance and week tended to be significant (F(6,40)=1.96; P<0.10). At 5 weeks of age, calves kept at 4 or 3 m(2) per calf performed more locomotor play in the home environment than calves at 2.2 or 1.5 m(2) per calf (68, 74, 38 and 39 s for 4, 3, 2.2 and 1.5 m(2) per calf, respectively; F(3,15)=3.40; P<0.05), but in weeks 7 and 9, no effects of space allowance were found. In addition, the duration of locomotor play was recorded for all calves during an individual 10-min open-field test in a 9.6x4.8 m arena at 4 and 10 weeks of age. During the open-field test at 10 weeks of age, calves from pens with 1.5 m(2) per calf performed more locomotor play than calves on the remaining treatments (10, 9, 12 and 25 s for 4, 3, 2.2 and 1.5 m(2) per calf, respectively; F(3,15)=4.05; P<0.05). The present study shows that an increase in the available space increases the occurrence of locomotor play in the home environment at 5 weeks of age. It also shows that calves kept in pens with the smallest space allowance performed more locomotor play behaviour when released in a large arena at 10 weeks of age.  相似文献   

7.
This study examines different types of attachment measurements and pecking behavior in group-reared domestic chicks imprinted to a silent imprinting object. Immediately upon arriving from the hatchery, groups of heavy strain chicks were imprinted to a colored foam rubber ball for 72 h. The bond between these chicks and the imprinting object was then tested from 8 days until 5 weeks of age. Three days of imprinting sessions demonstrated that a strong attachment could be formed between the imprinted chicks and the imprinting object. In both experimental and control groups, the number of pecks was found to be significantly correlated with the latency measurements. It is, therefore, reasonable to consider the number of pecks of the imprinting object as another measurement for filial attachment.  相似文献   

8.
The objective of this experiment was to investigate the effect of rearing density on pecking behaviour and plumage during rearing and throughout the laying period in aviaries. Chicks were reared on sand at high (H; 13 m−2) or low (L; 6.5 m−2) density, in four rearing pens of 390 chicks and eight pens of 195 chicks, respectively, each pen measuring 30 m2. Proportions of chicks per pen performing various types of pecking behaviour were recorded by scan sampling during 16 observation bouts in each rearing pen at 6 weeks of age and during 24 observation bouts at 12 weeks. Individual body weights and plumage condition were recorded. Later, these pullets were housed at 17 hens m−2 in Tiered Wire Floor (TWF; 3 H and 3 L pens of 275 hens) and Laco-Volétage (2 H and 2 L pens of 275 hens) aviaries. At 35 weeks, two samples of eight hens from each aviary pen were observed for pecking behaviour in a test pen. Throughout the laying period, additional records were collected on pecking behaviour, body weight, plumage condition, egg production, and mortality. The L birds had better plumage condition at 6 weeks of age and throughout the laying period. These birds also ground pecked more frequently than H birds during rearing and the laying period. At 12 weeks, L birds feather pecked less than H birds, but no relationship was found between rearing density and feather-pecking behaviour during the laying period. Although TWF hens feather pecked more frequently than Volétage hens, there was no interaction between rearing density and type of aviary for the various pecking behaviours.  相似文献   

9.
We investigated whether the development of spatial behaviour of the domestic chicken is influenced by light exposure of the embryo, as is known to be the case for some other lateralized visual functions. Ninety-six chicks were incubated in the dark or exposed to light during the final days of incubation. Half of the chicks in each group had the experience of moving behind opaque screens from 10 to 12 days of age. The other half were given transparent screens as a control. Chicks were tested in a detour test and a rotated floor test and their dispersal in groups was observed in larger pens. In the rotated floor test, chicks that had had experience with opaque screens used distal cues significantly more often than chicks that had experience with transparent screens (P = 0.042), regardless of whether they had been exposed to light before hatching or incubated in the dark. There were no significant differences between treatments in the detour test or in the dispersal behaviour. Hence, visual lateralization has no influence on the development of the spatial behaviour that we tested, whereas the occlusion experience is quite specific and results in shifted attention to distal spatial cues.  相似文献   

10.
Modern intensive farming conditions lack the diversity of substrates present in more natural environments and offer young animals fewer opportunities for interaction. Evidence exists that this may affect the organization of interactive patterns of behaviour, but shifts in behavioural diversity have not been measured directly. We investigated the effect of the substrate in the home pen on the diversity of behaviour in young growing pigs, Sus scrofa. Over 5 months, 26 pigs were housed singly in either substrate-impoverished (SI) or substrate-enriched (SE) conditions. Once every month we recorded the behaviour of these pigs in detail both in the home pens and in two novel object tests. In addition, we calculated the diversity of behaviour shown by SI and SE pigs in the home pen and in the novel object tests, using a relative behavioural diversity index. In the two novel object tests, SI pigs were less mobile than SE pigs and focused their behaviour on particular substrates. In addition, SI pigs showed less diverse behaviour than SE pigs. Our results show that the less diverse behaviour of SI pigs previously recorded in their home pens persists under novel conditions, supporting the hypothesis that substrate-impoverished housing conditions structurally affect the organization of behaviour in young growing pigs. Copyright 2000 The Association for the Study of Animal Behaviour.  相似文献   

11.
The acute and long-term effects of Ca2+ and Pi on vitamin D metabolism were studied in vitro with isolated renal tubules from vitamin D-deficient and vitamin D-supplemented chicks. Ca2+ depletion, achieved by isolating renal tubules in Ca2+-free buffers, led to suppression of 1 alpha-hydroxylase activity. Re-introduction of Ca2+ during incubation caused an acute stimulation of this enzyme. This stimulatory effect of Ca2+ was prevented by prior treatment of Ca2+-depleted renal tubules for 6 h with 1,25-dihydroxycholecalciferol. Ca2+ and Pi produced marked acute affects on 1 alpha-hydroxylase activity, which persisted for the whole 8 h experimental period, in Ca2+-depleted renal tubules from vitamin D-deficient chicks. The effects of either ion were influenced by the concentration of the other. However, the effects of these ions could not be reproduced in either Ca2+-depleted renal tubules from vitamin D-supplemented chicks or in renal tubules from vitamin D-deficient chicks, isolated in Ca2+-containing buffers. Isolation of renal tubules from vitamin D-supplemented chicks in Ca2+-containing buffers and subsequent incubation for 8 h in the presence of increased [Ca2+] led to a modest but statistically significant suppression of 1 alpha-hydroxylase and stimulation of 24-hydroxylase activity. It is concluded that the acute effects of Ca2+ and Pi on 1 alpha-hydroxylase activity of Ca2+-depleted renal tubules from vitamin D-deficient chicks are not regulatory but the results of the experimental conditions. In contrast the long-term effects of Ca2+ on both hydroxylases of renal tubules from vitamin D-supplemented chicks may be of physiological significance.  相似文献   

12.
Chicken hepatic histidase activity varies with dietary protein consumption, but the mechanisms responsible for this alteration in activity are unclear. In the present research, the complete coding sequence and deduced amino acid sequence for chicken histidase was determined from clones isolated from a chicken liver cDNA library. The deduced amino acid sequence of chicken histidase has greater than 85% identity with the amino acid sequences of rat, mouse, and human histidase. In a series of four experiments, broiler chicks were allowed free access for 1.5, 3, 6, or 24 h to a low (13 g/100 g diet), basal (22 g/100 g diet) and high (40 g/100 g diet) protein diet. In the final experiment 5, chicks were allowed free access for 24 h to the basal, high protein diet or the basal diet supplemented with three different levels of l-histidine (0.22 g/100 g diet, 0.43 g/100 g diet or 0.86 g/100 g diet). There were no differences in the expression of the mRNA for histidase at 1.5 h, but at 3 h, histidase mRNA expression was significantly (P < .05) greater in chicks fed the high protein diet compared to chicks fed the low protein diet. At 6 and 24 h, histidase mRNA expression was significantly enhanced in chicks fed the high protein diet, and significantly reduced in chicks fed the low protein diet, compared with chicks fed the basal diet. Histidase mRNA expression was not altered by supplementing the basal diet with histidine. The results suggest that previously observed alterations in the activity of histidase, which were correlated to dietary protein intake, are mediated by rapid changes in the mRNA expression of this enzyme, and are not necessarily related to dietary histidine intake.  相似文献   

13.
How a Common Tern (Sterna hirundo) Colony Defends itself against Herring Gulls (Larus argentatus) The subject of this study is the anti-predator behaviour of a small common tern colony near a large herring gull colony on the island of Mellum, West Germany (Fig. 1). In 1980 the number of gulls crossing this tern colony increased during the terns' chick-stage (Fig. 4). Observed predation of tern chicks was independent of tide and time of day (3., Fig. 5). The frequency of tern reactions corresponded to the number of herring gull crossings (Fig. 5, Table 1). The terns' responses increased between morning and evening (Fig. 8). Tern up-flights and attacks increased absolutely and as a percentage, with the advance of the breeding season (Fig. 3, 4). They were positively correlated with the observed chick predation and the number of pairs with chicks, most markedly with chicks older than 5 days (Figs. 3, 4; Table 1). This increased defence was maintained by fewer pairs as, by then, many had lost their own broods (Fig. 4). As the breeding season progressed, herring gulls increasingly became the main cause of tern up-flights and the object of the attacks (Figs. 9–11). The up-flights of the whole colony, which occurred frequently and spontaneously during incubation, were observed only rarely after hatching and were almost exclusively a response to herring gulls (Figs. 10, 12). The lower herring gulls flew over the colony, the more frequently common terns flew up or attacked and the more individuals were involved in these responses (Figs. 6, 13, 14). During the breeding period, communal up-flights and attacks by terns increased as a percentage (Figs. 12, 13, 15–17). Group-attacks effected changes in the gulls' flying-routes more often than did individual attacks (Fig. 18). Despite the defence behaviour and its adaptation to the predation pressure, herring gulls often succeeded in robbing chicks. This is why the breeding success of the common tern was poor (< 0.4 chicks/nest). Possible reasons for this are discussed.  相似文献   

14.
AIMS: To determine the effect of antimicrobial selective pressure on the transmission of antimicrobial resistant and sensitive strains of Salmonella in poultry. METHODS AND RESULTS: Eight pens housed 12 broiler chicks each. Two chicks in four of the pens were inoculated with a Salm. Typhimurium strain resistant to 12 antimicrobials (including tetracycline), and two chicks in each of the four other pens were inoculated with a strain sensitive to all antimicrobials tested. Two pens inoculated with each strain were treated with chlortetracycline and two were not. Chicks were killed on day 7 and caeca were cultured for Salmonella. Experiments were performed independently twice. Chicks exposed to pen mates inoculated with the resistant strain and treated with tetracycline were 90% positive for Salmonella; whereas 60% of chicks given no antimicrobials were positive. Chicks exposed to the sensitive strain were 95% positive with tetracycline treatment and 90% positive without treatment. CONCLUSIONS: A multidrug-resistant Salm. Typhimurium strain had significantly increased transmission when chicks were treated with tetracycline. Transmission of a sensitive strain was not inhibited by antimicrobial selective pressure at recommended therapeutic dose. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates that antimicrobial usage may influence the transmission of antimicrobial-resistant pathogens in poultry.  相似文献   

15.
Liver biopsies were performed on starved chicks at 0 and 4 h after refeeding a fat-free diet. Fatty acid synthetase activity increased after refeeding, and administration of cycloheximide did not prevent the rise of enzyme activity. Incorporation of [carboxyl-14C]leucine into fatty acid synthetase was measured in enzyme purified from the livers of starved chicks, starved-refed (4 h) chicks, and starved-refed chicks injected with cycloheximide. The data suggest that the synthesis of enzyme protein was inhibited in starved and cycloheximide-treated refed chicks in comparison with refed chicks. Liver cytosol from fed or starved chicks was filtered through centrifuge ultrafiltration membranes and the residues were suspended in the same or opposite filtrates. Fatty acid synthetase activity in residues from starved chicks was stimulated when suspended in filtrates from fed chicks. The evidence is consistent with the hypothesis that a portion of the fatty acid synthetase in the liver of starved chicks is present as an inactive form which can be activated upon refeeding.  相似文献   

16.
ABSTRACT. The circadian locomotor (walking) rhythms of individual forager honeybees ( Apis mellifera ligustica L.) were measured under a variety of conditions. In constant dark the rhythms exhibited endogenous periodicities that were less than 24 h, whereas under constant light the periods tended to be greater than 24 h. Individual honeybees readily entrained to photoperiods, displaying a diurnal pattern of entrainment with most of the activity occurring in late photophase. Evidence is presented which suggests that foraging behaviour and general locomotor behaviour may be governed by two different circadian clock systems.  相似文献   

17.
Hatching concepts such as on-farm hatching provide an opportunity to supply newly hatched chickens with optimal nutrition that support growth and development of a healthy gut. Brown algae contain bioactive compounds, especially laminarin and fucoidan that may improve intestinal health and immune responses. This study aimed to examine the effects of early access to feed and water posthatch and feed supplementation with algal extract rich in laminarin from Laminaria digitata, on growth performance, organ and microbiota development and antibody production. A total of 432 Ross 308 chicks were allotted to 36 rearing pens in a 2 × 3 factorial design with two hatching treatments and three dietary treatments. During chick placement, half of the pens were directly provided access to feed and water (Early) while half of the pens were deprived of feed and water for 38 h (Late). The chicks were fed three different starter diets until day 6; a wheat-soybean meal-based control diet, a diet with low inclusion of algal extract (0.057%) and a diet with high inclusion of algal extract (0.114%). Feed intake and BW were registered on pen basis at placement, days 1, 6, 12, 19, 26, 33 and 40. To induce antibody responses, all chicks were vaccinated against avian pneumovirus on day 10. Three chicks per pen were selected as focal animals and used for blood sampling on days 10 and 39. On days 6, 19, and 40, two birds per pen were killed and used for organ measurement and caecal digesta sampling for gut microbiota analysis using the Illumina Miseq PE 250 sequencing platform. Results showed that algal extract did not influence gut microbiota, gut development or vaccine-induced antibody responses. However, during the first 38 h, early-fed chicks consumed on average 19.6 g of feed and gained 27% in BW, while late-fed chicks lost 9.1% in BW which lowered BW and feed intake throughout the study (P < 0.05). Late chicks also had longer relative intestine, higher relative (g/kg BW) weight of gizzard and proventriculus but lower relative bursa weight on day 6 (P < 0.05). No effects of hatching treatment on microbiota or antibody response were detected. The microbiota was affected by age, where alpha diversity increased with age. In conclusion, this study showed that early access to feed but not algal extract improved the growth performance throughout the 40-day growing period, and stimulated early bursa development.  相似文献   

18.
《Animal behaviour》1988,36(3):675-683
When given a simultaneous choice preference test 24h after being allowed a period of time in running wheels, dark-reared domestic chicks, Gallus gallus domesticus, will approach a stuffed jungle fowl in preference to a red box. The present study was designed to determine which aspects of the stuffed fowl were critical for the emergence of this preference. In all experiments the preferences of dark-reared chicks were studied in a test involving the simultaneous presentation of an intact stuffed jungle fowl and a second, test object. In experiment 1 this object was a ‘complex’ red box, in experiments 2.1 and 2.2 disarticulated stuffed fowl, and in experiment 2.3 the ‘scrambled’ skin of a jungle fowl. The results of these experiments suggested that particular arrangements or configurations of features, and not outline or textural complexity alone, are important for the emergence of the predisposition. Further support for this hypothesis was obtained in experiment 2.4 in which the intact fowl was compared to a test object containing such configurations of features. The result of experiment 3 suggested that the configuration of features associated with the head and neck region are particularly important, while the results of experiments 4 and 5, in which the test objects were a stuffed gadwall duck and a stuffed polecat, respectively, established that the configuration of features esential for the predisposition is not species specific.  相似文献   

19.
The objective of this study was to develop a procedure for estimating the standardized mineral (calcium, Ca; phosphorus, P; copper, Cu; manganese, Mn; zinc, Zn) availabilities (SMA) in soybean meal for broilers. In experiment 1, twelve 24-day-old male chicks were used to determine the length of the pre-experimental fasting period needed to empty the total tract of feed residues. Feed was removed and excreta samples were collected for 12, 24, 36 or 48 h after feed withdrawal, respectively. The result indicated that birds were fasted for at least 24 h after feed withdrawal in order to ensure that no previous feed residues remained in the digestive tract of chicks. In a subsequent experiment, forty-eight 24-day-old male chicks were used to determine SMA in soybean meal. Chicks were fasted for 24 h and then fed mineral-free or soybean meal diet for 4 h, and excreta samples were collected until 24 or 48 h after feed withdrawal. The results showed that the extended excreta collection time of 48 h after feed withdrawal was adequate for estimating SMA. The standardized availability values of Ca, P, Cu, Mn or Zn in soybean meal were 51.14%, 50.22%, 36.28%, 30.79% or 49.66%, respectively. In experiment 3, a similar bioassay was conducted with forty-eight 36-day-old male chicks to measure SMA in the same soybean meal. The standardized availability values of P (51.59%), Cu (36.37%), Mn (31.94%) or Zn (43.37%) were similar (P > 0.12) to the results of experiment 2 except for Ca (41.49%), indicating that the age of birds had no effect on the standardized availabilities of P, Cu, Mn or Zn in soybean meal. The results from this study suggested that this simple and rapid procedure could be used to determine SMA in feedstuffs (e.g., soybean meal) for broiler chicks.  相似文献   

20.
The objective of this study was to investigate piglet use of the creep area, comparing litters of sows with a high vs. low breeding value for piglet survival in the first 5 days postpartum, that were either housed in crates or individual pens during farrowing and lactation. Seventy-five Yorkshire × Danish Landrace sows were video recorded for 4 days after farrowing, and the analysis was conducted using instantaneous sampling every 10 min commencing 24 h after the birth of the first piglet for a period of 72 h. Breeding value for piglet survival had no effect on piglet use of the creep area or time spent in any location of the farrowing environment. Farrowing environment had significant effects on piglet location; during all days there were significantly more piglets in the creep area in the crates compared to the pens (P < 0.01), and this difference was larger at 24–48 h than at 49–72 h and at 73–96 h after birth (P < 0.05). Piglets in pens spent significantly more time resting near the sow, excluded nursing (P < 0.001), and this percentage decreased over time after farrowing (P < 0.001) in both the crates and the pens. In conclusion, piglet use of the creep area was higher in the crate compared to the pen particularly during the second day of life. This may partly be due to a much larger proportion of uncomfortable, slatted floor in the crates, and the shorter distance from the sow to the creep area in the crate.  相似文献   

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