• Asian-Australasian Journal of Animal Sciences
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• v.14 no.6
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• pp.765-770
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• 2001

Thirty second parity sows of the synthetic Nepalese Pakhribas genotype were used to investigate factors which might improve the occurrence and expression of estrus. The experiment had two sequential elements. In part 1, a change in suckling pattern was applied during lactation, and in part 2, different estrus detection methods were evaluated after weaning. All sows received the same pattern of weaning, which imitated the progressive weaning system used in Nepalese villages. Piglets from each litter were weaned at three ages (6, 7 and 8 weeks of age) in the proportion of 0.5 at 6 weeks followed by 0.25 at each of the subsequent weanings. In the first lactation treatment, the suckling pattern was left undisturbed, similar to the practice used in the villages in which the remaining piglets after first weaning are allowed continuous suckling. In the other treatment, the remaining piglets after first weaning were allowed to suckle their sows only during the night, whilst in the day time (09:00-16:00) they were excluded from the sow but left free to roam around. After weaning, estrus detection procedures were carried out in the absence or presence of two different boar stimuli: a synthetic boar pheromone spray or fresh boar urine. These were applied sequentially in a sequence of testing that alternated for each sow on a daily basis. The weaning to re-mating interval was significantly longer for the unrestricted suckling treatment. All sows were re-mated within 30 days after first weaning in the restricted suckling treatment groups, whereas only 71% of sows were re-mated within 30 days after weaning in the unrestricted suckling treatment groups ($x^2=3.877$, 1df, p<0.05). Both boar pheromone spray and boar urine increased the estrus detection probability, with no significant differences between the two stimuli treatments.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.8
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• pp.1176-1181
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• 2005

This study investigated the effects of restricted suckling (RS) on some physiological and behavioural stress parameters compared to temporal weaning (TW). Twenty Brahman (Bos indicus) cow-calf pairs were assigned to one of two groups: Calves in the RS group were limited to suckle their dams once daily for 30 min during days 30 to 33, while calves in the TW group were removed from their dams during days 59 to 62 postpartum. Heart and respiratory rates, serum cortisol concentration and body temperature were registered in cows and calves. In addition, the number of steps was also registered in calves. All parameters were recorded 24, 48 and 72 h after the beginning of the two treatments, respectively. In TW calves, higher (p<0.05) cortisol concentration and number of steps were recorded in the 1st samples and 1$^{st}$ and 2$^{nd}$ observations, respectively. No difference was found in body temperature between treatments. However, respiration and heart rates differed in the 1$^{st}$ and 2$^{nd}$ observations, respectively. In general, a significant decrease (p<0.05) in these three parameters was observed over time. In cows, no differences were found in cortisol concentration or body temperature between treatments or with time. Heart and respiratory rates were lower (p<0.05) in the TW treatment only 24 h after beginning of treatment. It was concluded that (a) RS resulted in less behavioural and physiological indices of distress compared to TW in calves, although in general, differences were found only in some variables, mainly during the 1$^{st}$ day following start of the treatment, and there in a chance of age effects. (b) Cows were less affected than their young, regardless of the treatment applied.

• Korean Journal of Animal Reproduction
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• v.24 no.1
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• pp.35-40
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• 2000

This experiment was conducted to investigate how restricted-lactation and regulation of weaning-time influence the levels of insulin-like growth factor-I (IGF-I) in primiparous rats during the suckling period. All the rats were raised in the individual cage from a few days before parturition through the whole suckling period. The restrictedlactation (RL) and weaned (W) groups were subdivided into 5 subgroups as RL0, RL5, RL10, RL15 and RL20 as well as W0, W5, Wl0, W15, and W20 according to the day of onset of suckling only 4 pups in restriction lactation and of suckling no pups in weaned group, respectively, in contrast to suckling 8 pups per litter in normal lactation (NL) group. The results obtained were summarized as follows: 1. The serum IGF- I concentration of NL rats was 750.59$\pm$3.52ng/$m\ell$ on Day 0, which was not changed until Day 15, and then it was increased through the subsequent suckling period to 1690.20$\pm$4.42ng/$m\ell$ on Day 25. 2. The IGF-I concentrations of early restricted lactation (RL0, RL5) were 1395.90$\pm$3.45ng/$m\ell$ and 1351$\pm$3.23ng/$m\ell$ on Day 10, respeotively. It was significantly higher (P＜0.05) than NL group (745.96$\pm$2.24ng/$m\ell$), and then was not different between group from day 15 of lactation. 3. The IGF- I concentration of W-group in the early lactation was higher (P＜0.05) than NL group during the first week of lactation. But it was decreased to the similar concentration as NL group on Day 10. These data show that lactation stimulus may regulate the IGF-I concentration.

• Korean Journal of Animal Reproduction
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• v.23 no.2
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• pp.95-103
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• 1999

This experiment was conducted to investigate how the lactation regulation such as restricted-lactation and early weaning during the suckling period influences on ovarian functions and change in serum levels of progesterone in primiparous rats. All the rats were raised in the individual cage from a few days before parturition through the suckling period. The normal lactation(NL) groups were controled 8 pups. The restricted-lactation(RL) and weaned(W) groups were subdivided into 5 subgroups as RL0, RL5, RL10, RL15 and RL20 as well as W0, W5, W10, W15, and W20 according to the day of onset of suckling. The number of pups were regulated from 8 to 4 on experimental strating day in RL gropus, and also perfectly weaned on the each on-set day in W groups. The results obtained were summarized as follows: 1. During the whole suckling period of 25 days the pups in RL group grew significantly(P＜005) faster than those in normal-lactation(NL) group. The pups in earlier RL group grew significantly(P＜0.05) faster than those in later RL rats, and there was no found any significant difference in body weight of pups between RL20 and NL group. The gestation period and litter size were found to be 21.53$\pm$0.04 days and 13.75$\pm$0.07, respectively. 2. The estrous cycle was not expressed in the NL group through the whole suckling period. An irregular estrous cycle was found around day 20 in RL0 group, and the regular estrous cycles were exhibited continuously from day 10 in the day 0 weaned rats. 3. In the rats of NL group the serum progesterone concentration increased from 33.16$\pm$2.64ng/$m\ell$ on day 0 to 122.5$\pm$53.68 ng/$m\ell$ on day 10, and then decreased slightly to 97.30$\pm$3.21 ng/$m\ell$ on day 20, but then decreased abruptly. However, the serum level of progesterone decreased greatly(P＜0.05) in 5 to 10 days following suckling restriction in the rats from which suckling began to be under restriction on day 0 or day 15. In the early weaning group the significant ( (P＜0.05) decrease in progesterone concentration was found similarly in 48 hours following weaning in all the rats weaned on day 0 through day 20. It was suggested that lactation stimulation is a very pivotal on the function of ovary.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.1
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• pp.68-76
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• 1999

A formal survey was carried out in Nharira-Lancashire areas located in Chivhu to assess the calf rearing systems practiced in smallholder dairy farming areas of Zimbabwe. A total of 47 farmers, collectively owning 305 cows and 194 calves of various breeds, participated in the survey. All the farmers allowed their calves to suckle their dams all day to obtain colostrum. The colostrums intake period was significantly (p < 0.05) shorter (5.2 vs 4.1 days) in the small scale commercial area (SSCA) compared to communal area (CA). Milk was first sold to the Nharira-Lancashire Milk Centre a day after the colostrum intake period ended. Most of the CA (91.3%) and SSCA (77.8%) farmers penned their cows and calves together at night during the colostrum intake period. Thereafter the calves were penned separate from their dams. After colostrum intake, two types of calf suckling systems were practised; twice a day suckling and twice a day then changed to once a day suckling. In both systems, suckling was allowed for 30 minutes after the cows had been hand milked. There was no significant (p < 0.05) difference in the mean weaning age of calves between the CA and SSCA (5.8 vs 5.4 months). The most common weaning method was through separation of the calves from the dams. The limitaitions to calf production in Chivhu were the prohibitively high costs of calf meals, poor feed resources during the dry season, a general lack of knowledge on calf rearing diseases and inappropriate calf housing.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.5
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• pp.738-748
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• 2012

One of the main goals of small, medium and large farms is to improve the reproductive performance of rabbit does. Stocks of lower productivity can be improved by crossing with intensive breeds. A better nutritional status of both foetuses and suckling kits has a positive effect on their later productivity. Overfeeding young females before first mating can lead to conditions of fattiness. Using restricted feeding or higher fibre content in the feed and changing it for a higher level ad libitum feeding about one week prior to first mating leads to longer lifespan and higher productive level. Intensive reproductive rhythm creates a negative energy balance in does : they are unable to consume enough feed (energy) for the nutritional requirements of foetus and lactation, and therefore lose most of their fat reserves. Furthermore, primiparous does also expend energy because they are still growing. Under intensive conditions, the 42-d reproductive rhythm (re-mating 11 days after parturition) is recommended. Under extensive conditions, the 18 or 25-d mating interval with 35 to 42-d weaning could be suitable. On small farms, natural mating is favoured; on large farms AI is commonly employed. The main advantage of AI is the all-in, all-out system. Hormonal (PMSG) treatment is used with AI to increase receptivity on d 11. Frequent and high level PMSG use can lead to higher anti-PMSG antibody rates. Lower level (max. 20 IU) and less frequent PMSG injection or non-hormonal alternative methods (short dam-litter separation, changing nursing method or lighting programs) are recommended for this reason.

• Journal of Animal Science and Technology
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• v.52 no.4
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• pp.271-280
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• 2010

This study was conducted to investigate the effects of Aspergillus niger-derived multi-enzyme complex supplementation to feedrestricted lactating sows on performances, milk yield, blood profiles, and manure excretion as compared with ad libitum-fed sows without supplementation of enzyme. Fifty multiparous lactating Berkshire sows were allotted to 5 treatments of 10 sows per treatment during a 28-d lactation period and litter per sow was standardized to 9 suckling piglets. Treatments were ad libitum-fed sows without enzyme and feed-restricted sows supplemented with four increasing levels (0, 0.02, 0.04 and 0.08%) of multi-enzyme complex derived from Aspergillus niger. Blood samples from all sows were collected to determine serum metabolite concentrations before the morning feeding on d 27 of lactation. Litter body weight and a piglet weight at weaning, and litter weight gain significantly (P<0.05) increased with increasing levels of multi-enzyme complex, but there was no significant difference between ad libitum-fed sows without enzyme and feed-restricted sows supplemented with multi-enzyme complex. Body condition score and backfat depth at weaning significantly (P<0.05) increased as multi-enzyme complex level increased. Lactational backfat depth tended (P>0.05) to less decrease with increasing levels of enzyme complex. Serum inorganic phosphorus and non-esterified fatty acid concentrations significantly (P<0.05) increased with increasing levels of enzyme complex. Daily milk yield was not significantly different across treatments, but milk fat yield significantly (P<0.05) increased as multi-enzyme complex level increased. Manure output was significantly (P<0.01) higher for ad libitum-fed sows than for feed-restricted sows, but there was no significant difference among feed-restricted sows supplemented with increasing levels of multi-enzyme complex. Fecal phosphorus amount significantly (P<0.05) decreased with increasing levels of multi-enzyme complex. Feed costs of sows per litter weight gain were reduced by 1.25% to 9.67% with increasing levels of multi-enzyme complex as compared with ad libitum-fed sows without enzyme. The results indicated that multi-enzyme supplementation to feed-restricted lactating sows not only increased litter performances, but also was comparable to ad libitum-fed sows, resulting in reduced feed costs. Moreover, the reduction of fecal phosphorus amount with increasing levels of enzyme complex would contribute to the reduction of environmental pollution.