Effect of slaughter-house offal and fish levels on production performance in mink and blue fox

Open Jou nal o Animal Sciences, 2014, 4, 237-243 Published Online Oc obe 2014 in SciRes. h p://www.sci p.o g/jou nal/ojas h p://dx.doi.o g/10.4236/ojas.2014.45030 How o ci e his pape : Ko honen, H.T. (2014) E ec o Slaugh e -House O al and Fish Le els on P oduc ion Pe o mance in Mink and Blue Fox. Open Jou nal o Animal Sciences, 4, 237-243. h p://dx.doi.o g/10.4236/ojas.2014.45030 E ec o Slaugh e -House O al and Fish Le els on P oduc ion Pe o mance in Mink and Blue Fox Hannu T. Ko honen MTT Ag i ood Resea ch Finland, Animal P oduc ion Resea ch, Kannus, Finland Email: Hannu. .ko honen@m . i Recei ed 4 July 2014; e ised 22 Augus 2014; accep ed 6 Sep embe 2014 Copy igh © 2014 by au ho and Scien i ic Resea ch Publishing Inc. This wo k is licensed unde he C ea i e Commons A ibu ion In e na ional License (CC BY). h p://c ea i ecommons.o g/licenses/by/4.0/ Abs ac The p esen s udy e alua es g ow h, u p ope ies, heal h condi ion and ep oduc ion pe o - mance in mink (Neo ison ison) and blue ox (Vulpes lagopus) du ing g owing- u ing and ep o- duc ion pe iods. Die s compa ed we e: Die A, which was composed o a high amoun o slaugh- e -house o al bu less ish p oduc s han no mal, and die B, which was composed o low amoun s o slaugh e -house o al bu inc eased ish p oduc ion con en . Whelping succeeded be e in ani- mals on die B han on die A. The di e ence in whelping esul be ween die s was 0.6 ki s/ma ed emale o mink (P < 0.05) and 0.4 ki s/ma ed emale o blue ox. A age 6 weeks, he di e ence was signi ican (P < 0.05) only in mink, i.e., 0.8 ki s/ma ed emale. Calcula ed pe whelped emale, he di e ence was mos p onounced in mink (0.6 ki s; P < 0.05). The weigh s o ixens a 6 weeks we e simila wi h die s A and B in bo h species. In mink and blue ox, he body weigh s o male and emale ki s we e highe wi h die B (P < 0.05). Du ing he g owing pe iod, weigh gain was be e wi h die B (P < 0.05). Final body weigh s we e highe in males on die B (P < 0.05). A simila en- dency was ound in emales. In blue ox, he skin was signi ican ly longe in animals on die B (P < 0.05). Signi ican di e ences we e no ound in u mass, co e o quali y. In mink, skin leng h was simila in bo h die s. Signi ican di e ences we e no ound in u p ope ies be ween he die g oups. The conclusion is ha die B can be be e ecommended ins ead o die A. Keywo ds Fa med Fu bea e s, Feed Ing edien s, G owing, Rep oduc ion, Fu P oduc ion 1. In oduc ion The main ing edien s in u animal eed a e p oduc s o he ish and slaugh e indus ies. Typically hei amoun s H. T. Ko honen 238 a y by yea and season [1]-[4]. Di e en die s a e o en manu ac u ed o a med mink and oxes. The mink (Neo ison ison) is a semi-aqua ic mus elid (Family Mus elidae) whose li ing en i onmen in he wild is associ- a ed wi h wa e sys ems such as s eams, i e banks, lake sho es and ma ine sho e ma shes. The amoun o aqua ic ood, e.g., in e eb a es and ish, in i s die anges om 30% o 70% [5] [6]. Thus, mink has adap ed o subs an ial a ia ions in he composi ion o eed. On u a ms oday, ish p oduc s accoun o app oxima ely 30% o o al ood supply. The o he common u bea e on u a ms is blue ox, a colou ype o he wild A c ic ox (Alopex lagopus). The composi ion o he die o wild oxes ypically a ies e en mo e han does ha o mink [7] [8] [9]. In an A c ic habi a , oxes end mainly o ea mea and ood sc aps whe eas in a coas al a ea, hei die may comp ise mainly e en ish [10]. Foxes ha e he e o e adap ed o ma ked egional, annual and seasonal luc ua ions in ood a ailabili y and con en . Al hough a med mink and blue ox ha e been ed ish and slaugh e -house p oduc s o mo e han 50 yea s, we s ill lack su icien unde s anding on he p ope use o hese speci ic ing edien s [3] [9] [11] [12]. P e iously, a s udy on e ec o slaugh e house o al and ish mix u e on p oduc ion pe o mance o blue and sil e oxes has been ca ied ou [13]. Slaugh e house die did no con ain ish and, co espondingly, ish die did no con ain slaugh e house o al. The e we e no g ea di e ences be ween die s in he body weigh s o animals a pel ing. Fu cha ac e is ics, on he o he hand, we e be e in bo h species on ish mix u e based die [13]. In he p esen s udy, a med mink and blue ox we e ed wi h wo di e en die s. Die A comp ised a high amoun o slaugh e - house o al bu a lowe amoun o ish p oduc s han no mal. Die B comp ised lowe amoun s o slaugh e - house o al bu inc eased ish p oduc con en . The aim was o cla i y he e ec s o hese wo di e en die s on g ow h pe o mance and u p ope ies in ju eniles and on ep oduc ion esul in adul s. 2. Ma e ial and Me hods 2.1. Expe imen al Animals and Se -Up The s udy was pe o med a he Fu Fa ming Resea ch S a ion, Kannus (MTT) du ing wo seasons: 1) he b eeding pe iod om Ma ch o June, and 2) he g owing pe iod om July o No embe . The use o expe imen al animals was e alua ed and app o ed by he Animal Ca e Commi ee o MTT Ag i ood Resea ch Finland. The animals we e s anda d colou ed da k mink and blue ox. All animals we e bo n in May. Only heal hy animals ee om plasmocy osis we e used. S udy g oups we e made gene ically equal so ha one ki om same li e was placed o each g oup. Expe imen al die g oups we e: 1) Die A, which was composed o a high amoun o slaugh e -house o al and a low amoun o ish p oduc s; and 2) Die B, which was composed o lowe amoun s o slaugh e -house o al bu inc eased ish p oduc con en (see Table 1 and Table 2). The g oups in he g ow- ing expe imen we e o med a weaning (9 July) and comp ised ki s selec ed om hose bo n in he b eeding expe imen . N = 60 mink and N = 40 blue oxes o bo h sexes we e used o he g owing expe imen . 48 mink and 70 blue oxes o bo h sexes we e selec ed o he ep oduc ion expe imen . The gene al heal h o he animals was checked daily. Heal h e alua ion was based on gene al appea ance o animals, including consis ence o aeces. The animals we e housed singly o he ep oduc ion expe imen and in pai s o he g owing expe imen . The mink cages we e 70 cm long × 30 cm wide × 38 cm high. Each cage also con ained a wooden nes box (22 cm wide × 30 cm long × 40 cm high) wi h ample bedding ma e ial (hay, s aw). Daily ou ine ea men s we e con- duc ed acco ding o s anda d a ming p ocedu es [9]. The ox cages we e 105 cm long × 115 cm wide × 70 cm high. Each cage had a wi e-mesh pla o m (105 cm long × 25 cm wide) and a wooden block o chewing (di- ame e 7 cm, leng h 35 cm). 2.2. Die s and Feeding De ails o he aw ma e ials and chemical composi ions o he expe imen al die s a e shown in Table 1 and Ta- ble 2. Die s we e he same h oughou he s udy. Vi amins pe kg o ood we e: e inol 1.05 mg; cholecalci e ol 0.009 mg; alpha- okophe ol 40 mg; hiamine 15 mg; ibo la in 6 mg; cyanocobalamin 0.02 mg; pan o henic acid 5 mg; nico ine acid 10 mg; py idoxine 3 mg; olic acid 0.3 mg; bio in 0.04 mg (Table 1). Fu he mo e, 1 kg mix u e ood con ains: calcium 16.0%; phospho us 11.0%; magnesium 4.0%; cobal 40 mg; coppe 150 mg; i on 6500 mg; manganese 3000 mg; zink 6000 mg. F eshly mixed eed was supplied wice a day du ing July-mid-Sep embe . The ea e , animals we e ed once a H. T. Ko honen 239 Table 1. Composi ion o expe imen al die s (%) wi h i amin con en 1. Ing edien s Die A Die B Slaugh e house o al 50.0 26.0 Fish o al2 - 15.0 Fish mix u e2 15.0 16.0 Cooked ba ley 3.0 5.5 Soybean oil 0.5 2.1 Po a o mass - 0.5 Wa e 31.5 34.9 1Vi amins pe kg o ood: e inol 1.05 mg; cholecalci e ol 0.009 mg; alpha- okophe ol 40 mg; hiamine 15 mg; ibo la in 6 mg; cyanocobalamin 0.02 mg; pan o henic acid 5 mg; nico ine acid 10 mg; py idoxine 3 mg; olic acid 0.3 mg; bio in 0.04 mg; 2Cod 50.0%, Bal ic he ing 50.0%. Table 2. Chemical composi ion and calcula ed con en s o me abolizable ene gy (ME) in expe imen al die s. Va iable Die A Die B D y ma e (DM), % 31.6 28.6 In DM%, ash 11.7 10.8 C ude p o ein 47.3 45.0 C ude a 22.8 19.4 C ude ca bohyd . 18.2 24.8 ME (MJ/kg DM) 17.7 16.8 F om ME%: p o ein 42.9 42.9 Fa 46.2 41.5 Ca bohyd . 10.9 15.6 day. The eed was dispensed by a comme cial eeding machine. Le o e s we e collec ed he nex day. Wa e ing was au oma ic ad libi um. Daily eed po ions we e adjus ed acco ding o he animals’ appe i e and seasonal s anda ds [12] [14]. The a e age amoun o eed gi en o mink daily was 250 g/animal and o oxes 800 g/ani- mal. 2.3. B eeding Expe imen Animals we e ma ed acco ding o no mal ma ing ou ines [12] [15]. Be o e he b eeding season, he es icles o b eeding males we e palpa ed o check no mali y. Mink emales we e ma ed acco ding o he 1 + 8 sys em [1] [16]. Foxes we e a i icially insemina ed acco ding o no mal a ming p ac ice. All ixens we e p imipa ous. Con en ional b eeding boxes (60 cm long × 45 cm wide × 45 cm high) we e placed inside he cages wo weeks a e he animals had ma ed. A whelping, he da e o pa u i ion and he numbe o li e-bo n and s illbo n ki s we e eco ded. The whelping esul was calcula ed a 1 day and 6 weeks. Vixens and ki s we e weighed a age 6 weeks wi h a Me le SM 15 balance, accu acy ±1 g. 2.4. G owing Expe imen Ini ial and inal body weigh s we e measu ed wi h a Me le SM 15 balance, accu acy ±1 g. Haemoglobin was measu ed in male mink in July and Sep embe [12] [17]. The animals we e pel ed acco ding o he con en ional pel ing p ocedu es used on a ms. Mink we e killed by engine-p oduced CO and oxes by elec ic shock. Fu p ope ies we e e alua ed by he Finnish Fu Sales Co a he Fu Cen e , Van aa. The u cha ac e is ics e alu- a ed we e colou , mass, co e , o e all imp ession and quali y [9] [18] [19]. The scale anged om 1 (poo es ) o H. T. Ko honen 240 10 (bes ). Ca cass examina ions we e ca ied ou by a e e ina y su geon immedia ely a e pel ing. 2.5. S a is ics S a is ical analyses we e pe o med by he Gene al Linea Models (GLM) p ocedu e o he S a is ical Analysis Sys em [19] using Tukey’s s uden ized ange (HSD) es and analysis o a iance [9] [12]. The expe imen al ac o in he s udy was he die . Da a a e gi en as mean ± s anda d de ia ion (SD). 3. Resul s 3.1. B eeding Pe iod The appe i e o he animals was good. No dia hoea was ound. In mink, daily eed consump ion in Ap il was 207 g/animal wi h die A and 210 g/animal wi h die B. The daily consump ion alues in May we e 346 g and 355 g/animal, espec i ely. In June, mink emales on die A consumed 829 g/animal and hose on die B 854 g/animal daily. In blue ox, daily eed consump ion in Ap il was 264 g/animal wi h die A and 243 g/animal wi h die B. The daily eed in ake alues in May we e 576 g and 456 g/animal, espec i ely (P < 0.05). In June, he a e age daily consump ion o blue ox ixens on die s A and B was 1646 and 1636 g/animal, espec i ely. The animals’ heal h was good. Rep oduc ion esul s a e gi en in Table 3. Whelping pe o mance ended o be be e in animals ecei ing die B. This held ue o bo h species. In mink and blue ox, he whelping di e ence be ween die s a bi h was 0.6 ki s/ma ed emale wi h die A (P < 0.05) and 0.4 ki s/ma ed emale wi h die B. A age 6 weeks he di e - ence was clea only in mink, i.e., 0.8 ki s/ma ed emale (P < 0.05). Calcula ed pe whelped emale, he di e - ence was highes a 6 weeks in mink (0.6 ki s; P < 0.05). The body weigh s o ixens a age 6 weeks we e simila o bo h species wi h die s A and B (Table 4). In bo h mink and blue ox, he body weigh s o male and emale ki s we e highe wi h die B. 3.2. G owing Pe iod Body weigh s and u p ope ies a e shown in Table 5 and Table 6. In bo h sexes, weigh gain was be e in ani- mals on die B (P < 0.05). Final body weigh s we e highe in males on die B (P < 0.05). A simila endency was no ed in emales. In blue ox, he skin was also signi ican ly longe in animals on die B (P < 0.05). Signi ican Table 3. Rep oduc i e pe o mance in mink and blue ox ixens. Fo die s see Table 1. S a is ical signi icance be ween die s wi hin species: *P < 0.05. Blue ox Mink Va iable Die A Die B Die A Die B Ma ed emales, N 48 48 70 70 Whelped emales, N 42 44 53 58 Ba en emales, N 6 4 16 12 Females los ki s, N A 1 day 2 3 - - A 6 weeks 5 4 4 1 Ki s pe ma ed emale A 1 day 7.94 ± 3.0 8.35 ± 3.6 3.62 ± 2.4 4.23 ± 2.7* A 6 weeks 6.67 ± 4.6 6.9 ± 4.4 3.05 ± 2.6 3.87 ± 2.5* Ki s pe whelped emale A 1 day 9.07 ± 3. 2 9.11 ± 3.3 4.71 ±2.2 5.10 ± 2.8 A 6 weeks 8.65 ± 3.2 8.38 ± 3.5 4.03 ± 2.5 4.67 ± 2.6* H. T. Ko honen 241 Table 4. Body weigh s (g) o ixens and ki s a age o 6 weeks. S a is ical signi icance: *P < 0.05. Fo die s see Table 1. Blue ox Mink Va iable Die A Die B Die A Die B Vixens 5795.5 ± 552.5 5791.5 ± 593.9 897.8 ± 109.5 932.1 ± 125.4 Male ki s 1081.0 ± 206.7 1267.9 ± 260.5* 240.6 ± 65.3 304.3 ± 72.2* Female ki s 1062.1 ± 186.8 1227.4 ± 226.0* 219.9 ± 60.1 282.5 ± 63.2* Table 5. Body g ow h and u p ope ies in ju enile blue oxes. Ini ial body weigh s (BW) we e measu ed on 9 July, inal body weigh s we e measu ed on 18 No embe . Da a a e gi en as mean ± SD. Fu p ope ies we e e alua ed only in males. N = 40 animals. S a is ical signi icance: *P < 0.05. Va iable Die A Die B Ini ial BW, kg Females 1.81 ± 0.32 1.55 ± 0.41 Males 1.87 ± 0.32 1.61 ± 0.3 Final BW, kg Females 10.04 ± 1.37 10.56 ± 1.39 Males 11.11 ± 1.44 11.84 ± 1.32* Skin leng h, cm 66.0 ± 3.8 72.4 ± 3.0* Fu mass 6.5 ± 1.7 6.0 ± 1.8 Co e 8.0 ± 1.1 7.5 ± 1.8 Fu quali y 6.0 ± 1.6 5.6 ± 1.6 Table 6. Body g ow h, haemoglobin and u p ope ies in ju enile mink. Ini ial body weigh s (BW) we e measu ed on 9 July, inal body weigh s (BW) we e measu ed on 18 No embe . Da a a e gi en as mean ± SD. Fu p ope ies and haemoglobin we e e alua ed only in males. N = 60 animals. *P < 0.05. Va iable Die A Die B Ini ial BW, kg Females 543.0 ± 74.5 603.2 ± 72.9 Males 634.6 ± 106.6 789.0 ± 104.2 Final BW, kg Females 1192.6 ± 137.5 1292.3 ± 195.8 Males 1949.0 ± 321.5 2340.7 ± 280.4* Haemoglobin g/l 22 July 139.5 ± 8.6 127.0 ± 15.2 21 Sep embe 183.5 ± 9.0 182.7 ± 9.6 Skin leng h, cm 115.3 ± 3.6 115.1 ± 4.0 Fu mass 5.4 ± 2.0 6.5 ± 1.7 Co e 6.6 ± 1.5 7.3 ± 1.6 Gene al imp ession 6.9 ± 1.6 7.5 ± 1.8 Colou 8.3 ± 1.1 8.2 ± 1.0 Fu quali y 5.1 ± 2.1 6.2 ± 2.2 H. T. Ko honen 242 di e ences we e no ound in u mass, co e o quali y. In mink, skin leng h was simila in bo h die g oups. No we e he e any signi ican di e ences in u p ope ies be ween die s. The heal h o all animals was good. Haemoglobin alues did no di e signi ican ly be ween he mink g oups (Table 6). The appe i e o all animals was also gene ally good. No dia hoea was ound in any o he animals. Ca cass au opsies a pel ing e ealed sligh hype aemia in 9 colons o mink ed die A and in 8 o hose ed die B. Co espondingly, sligh hype aemia was ound in 9 oxes ed die A and in 7 ed die B. The a e age eed consump ion in mink on die A was 35.3 kg and in hose on die B 37.2 kg/animal o he en i e s udy pe iod (9 July-18 No embe ; P < 0.05). In oxes, he alues we e 105.9 and 104.7 kg/animal, e- spec i ely. The di e ence be ween die s is signi ican (P < 0.05) o mink bu no o oxes. 4. Discussion The i s pe iod o he p esen s udy comp ised he b eeding season, i.e., om Ma ch o June. The animals we e handled and ma ed acco ding o no mal a ming p ac ice. Thus, he esul s can be expec ed o apply well o comme cial a ming ou ines [3] [12] [20]. The ep oduc ion esul s indica ed ha whelping was less success ul in animals ecei ing die A, i.e., eed con aining a high amoun o slaugh e -house o al and a low amoun o ish. This esul was e en mo e p onounced in mink. In blue ox, on he o he hand, die also a ec ed he g ow h o young ki s. This was a ibu ed o he ma ked weigh di e ence be ween die g oups a age 6 weeks. The e - ec o die s was also e lec ed in he lowe numbe o ma ed emales in animals ed die A. The appe i e o a m mink and blue ox is no mally good du ing he g owing- u ing pe iod [3] [9] [12], as was also demons a ed by ou eed consump ion da a he e. The highe eed consump ion by animals on die B mos likely explains he g ea e body weigh gain in mink ecei ing die B. In blue ox, on he o he hand, eed in ake be ween die g oups did no di e signi ican ly. E en so, oxes on die B had highe inal body weigh s. This emp s us o conclude ha oxes can be e u ilize a die wi h a lowe amoun o slaugh e -house o al and a highe amoun o ish p oduc s. Die s o mink and blue ox may a y seasonally, annually and egionally in he wild [5] [6]. The blue ox is li ing in he a c ic egion [7] which means ha con en and a ailabili y o i s die ypically a ies mo e han in he mink [8]. Mink is a semi-aqua ic animal ha ha e used o a die wi h a highe amoun o ish han gi en he e in die A. Ac ually, 15% o ish in he die is less han hal he minimum amoun epo ed in he wild [5] [6]. I , he e o e, came as no su p ise ha a low amoun o ish had a nega i e e ec on he p oduc ion pe o mance o mink. In ou p e ious s udy, a high amoun o ish p oduc s in die s had a a ou able e ec on g ow h pe o m- ance, u p ope ies and diges ibili y compa ed wi h he no mal le el [9]. Mink as a semi-aqua ic mus elid-like ca ni o e is accus omed o ea ing se e al ypes o ish p oduc s bu also mea [5]. A highe amoun o slaugh e -house o al as such is he e o e unlikely o p oduce he ad e se e ec no ed he e: i was p obably mainly due o he low amoun o ish in die A [3] [20]. Blue ox is also a ca ni o e bu i s die in he wild no mally comp ises mo e mea han does ha o mink [7] [8]. He e, di e ences in die s be ween he s udied pa ame e s we e less p onounced in blue ox han in mink. This is a ibu ed o he ac ha he ox is physiologically mo e ca ni o ous han mink. In blue ox males, he highe inal body weigh in animals on die B was also seen as longe skin leng h a pel ing. This esul was expec ed as body weigh ma kedly a ec s skin leng h in his species [9] [21]. The skin leng h o emales was no measu ed. In mink, he e is also o en a clea co ela ion be ween skin leng h and body size [21]. The mink skins in he p esen s udy, howe e , we e o he same o de o magni ude despi e die and di e ences in inal weigh s. I would seem ha he die o mink did no ha e an ad e se e ec on ac ual body g ow h, only on he a ening p ocess. The heal h s a us o he animals s udied was gene ally good. Mo ali y was low in bo h mink and blue ox i - espec i e o hei die . The haemoglobin concen a ions measu ed we e also wi hin he ange o no mal alues [12] [17]. Fu he mo e, he e we e no ala ming indings in au opsies. The sligh hype aemia ound in he colon o bo h species is ypical unde a m condi ions. These obse a ions emp us o conclude ha bo h die s a e sui able o mink when e alua ed only om he animal wel a e poin o iew. In e ms o p oduc ion, howe e , die B was mo e sui able o bo h mink and blue ox. 5. Conclusion Die A was composed o a highe amoun o slaugh e -house o al bu a low amoun o ish p oduc s han no - H. T. Ko honen 243 mal. The s udy showed clea ly ha die A is less sui able han die B o bo h mink and blue ox. The same e- sul was ound du ing bo h he g owing- u ing and he ep oduc ion pe iods. Acknowledgemen s This s udy was inancially suppo ed by he MTT Ag i ood Resea ch Finland. The s a o MTT Resea ch S a- ion is kindly acknowledged o hei aluable help in ca ying ou his expe imen . Re e ences [1] Tauson, A.-H. (1985) E ec o Nu i ion on Rep oduc i e Pe o mance and Ki G ow h in Mink. Ph.D. Disse a ion, Repo 143, Uppsala. [2] Ko honen, H. and Niemelä, P. (1998) E ec o Ad Libi um and Res ic i e Feeding on Seasonal Weigh Changes in Cap i e Minks (Mus ela ison). 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